SECONDARY STAGE FLUID SEPARATION DEVICE CONNECTABLE WITH PRIMARY STAGE FLUID SEPARATION DEVICE

Abstract

A secondary stage sample separation device for separating at least a portion of a fluidic sample includes a fluidic interface configured for forming a fluidic coupling between a primary stage sample separation device and the secondary separation device, so that the fluidic sample separated by the primary stage sample separation device is fluidically suppliable to the secondary stage sample separation device via the fluidic interface for further separation, and a pressure reduction mechanism configured for reducing pressure at the fluidic interface at least in the event of an overpressure or of an excessive pressure increase.

Claims

1. A secondary stage sample separation device for separating at least a portion of a fluidic sample, wherein the secondary stage sample separation device comprises: a fluidic interface configured for forming a detachable fluidic coupling between a primary stage sample separation device and the secondary sample separation device so that the fluidic sample separated by the primary stage sample separation device is fluidically suppliable to the secondary stage sample separation device via the fluidic interface for further separation; a pressure reduction mechanism configured for reducing pressure at the fluidic interface at least in the event of an overpressure or of an excessive pressure increase.

2. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism is configured for preventing the overpressure from impacting the fluidically coupled primary stage sample separation device.

3. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism is configured for reducing pressure at the fluidic interface in the event of an overpressure or of an excessive pressure increase at a modulator valve of the secondary stage sample separation device.

4. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism is configured for reducing pressure at the fluidic interface in the event of an overpressure or of an excessive pressure increase generated by a temporary at least partial incapability of the secondary stage sample separation device to receive fluidic sample material from the primary stage sample separation device.

5. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism is configured for at least temporarily accommodating fluidic sample material in the event of a temporary at least partial incapability of the secondary stage sample separation device to receive fluidic sample material from the primary stage sample separation device.

6. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism is configured for preventing the primary stage sample separation device from pumping fluidic sample material against a fluidically blocking secondary stage sample separation device.

7. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism is arranged downstream of the fluidic interface and upstream of a modulator valve of the secondary stage sample separation device.

8. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism comprises a pressure relief valve.

9. The secondary stage sample separation device according to claim 8, wherein the pressure relief valve is arranged and configured: to disable flow of fluidic sample apart from a fluidic path between the fluidic interface and a modulator valve of the secondary stage sample separation device in the absence of overpressure; and to split off fluidic sample into a side path through the pressure relief valve away from the fluidic path between the fluidic interface and the modulator valve in the event of an overpressure.

10. The secondary stage sample separation device according to claim 8, wherein the pressure relief valve is configured as one of the following: a spring biased ball valve; a spring loaded plate valve; an electrically, mechanically, hydraulically or pneumatically controlled active valve; a first tube with a radial opening normally closed by an elastic second tube; a counter-pressure loaded ball valve or plate valve; an electrically driven valve.

11. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism comprises an elastic member being elastically expandable by fluidic sample material in the event of an overpressure to thereby temporarily accommodate fluidic sample material for reducing pressure.

12. The secondary stage sample separation device according to claim 11, wherein the elastic member is configured as a flow-through member arranged in a fluidic conduit between the fluidic interface and a modulator valve of the secondary stage sample separation device.

13. The secondary stage sample separation device according to claim 11, wherein the elastic member is arranged in a side path with regard to a fluidic conduit between the fluidic interface and a modulator valve of the secondary stage sample separation device to split off fluidic sample into the side path through the elastic member away from the fluidic path between the fluidic interface and the modulator valve in the event of an overpressure.

14. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism comprises a fluid restrictor having a higher fluidic impedance than and being in fluid communication with at least portions of a fluidic conduit between the fluidic interface and a modulator valve of the secondary stage sample separation device.

15. The secondary stage sample separation device according to claim 14, wherein the fluid restrictor is arranged in a side path with regard to the fluidic conduit between the fluidic interface and the modulator valve of the secondary stage sample separation device to split off fluidic sample into the side path through the fluid restrictor away from the fluidic path between the fluidic interface and the modulator valve in the event of an overpressure.

16. The secondary stage sample separation device according to claim 14, wherein the fluid restrictor is connected to a waste conduit.

17. (canceled)

18. The secondary stage sample separation device according to claim 1, wherein the pressure reduction mechanism comprises a side path branching off from a fluidic conduit between the fluidic interface and a modulator valve of the secondary stage sample separation device, wherein the side path comprises at least two redundant pressure reduction members.

19.-35. (canceled)

36. A sample separation system for carrying out a multiple stage separation of a fluidic sample, wherein the sample separation system comprises: a primary stage sample separation device for separating a fluidic sample; a secondary stage sample separation device according to claim 1 fluidically coupleable or coupled to the primary stage sample separation device via the fluidic interface and configured for separating at least a portion of the fluidic sample supplied and separated by the primary stage sample separation device

37. (canceled)

38. A primary stage sample separation device for separating at least a portion of a fluidic sample, wherein the primary stage sample separation device comprises: a fluidic outlet at which the separated fluidic sample is provided and which is fluidically coupled or suitable for being fluidically coupled to a fluidic interface of a secondary sample separation device so that the fluidic sample separated by the primary stage sample separation device is fluidically suppliable to the secondary stage sample separation device via the fluidic interface for further separation; a pressure reduction mechanism according to claim 1, configured for reducing pressure in the primary stage sample separation device at least in the event of an overpressure or of an excessive pressure increase due to the secondary stage sample separation device.

39. A method of carrying out a multiple stage separation of a fluidic sample, wherein the method comprises: fluidically coupling a primary stage sample separation device to a secondary stage sample separation device according to claim 1, by attaching a fluidic interface of the secondary stage sample separation device to a fluid outlet of the primary stage sample separation device; carrying out a primary stage separation of the fluidic sample by the primary stage sample separation device; carrying out a secondary stage separation of at least a portion of the fluidic sample by the secondary stage sample separation device by further separating at least a portion of the separated fluidic sample provided at the fluidic interface; after carrying out the primary stage separation and the secondary stage separation, detaching the fluidic interface from the primary stage sample separation device to thereby fluidically decouple the secondary stage sample separation device from the primary stage sample separation device; at least in the event of an overpressure or of an excessive pressure increase in the secondary stage sample separation device, reducing pressure for preventing a detector of the primary stage sample separation device detecting separation of the fluidic sample from being exposed to the overpressure.

40. (canceled)

Description

BRIEF DESCRIPTION OF DRAWINGS

[0070] Other objects and many of the attendant advantages of embodiments of the present invention will be readily appreciated and become better understood by reference to the following more detailed description of embodiments in connection with the accompanied drawings. Features that are substantially or functionally equal or similar will be referred to by the same reference signs.

[0071] FIG. 1 illustrates a two-dimensional sample separation system according to an exemplary embodiment of the invention constituted by a static primary stage sample separation device and a mobile secondary stage sample separation device flexibly and detachably connected to one another mechanically and fluidically at a waste conduit of the primary stage sample separation device via a fluidic interface, and configured for conforming the flow rates between the two stages at the fluidic interface in a self-sufficient way and without the necessity of involving a user.

[0072] FIG. 2 illustrates a three-dimensional view of a mobile secondary stage sample separation device mounted on a cart according to an exemplary embodiment of the invention.

[0073] FIG. 3 illustrates a detailed construction of a secondary stage sample separation device according to an exemplary embodiment of the invention.

[0074] FIG. 4 illustrates a one dimensional separation result (in particular a chromatogram) of a primary stage sample separation device presently operating as a standalone device.

[0075] FIG. 5 illustrates a two-dimensional separation result (in particular a chromatogram) of a sample separation system according to an exemplary embodiment of the invention constituted by the primary stage sample separation device of FIG. 4 and a secondary stage sample separation device according to an exemplary embodiment of the invention detachably connected to the primary stage sample separation device.

[0076] FIG. 6 illustrates a two-dimensional sample separation system according to an exemplary embodiment of the invention constituted by a primary stage sample separation device and a secondary stage sample separation device flexibly and detachably connected to the primary stage sample separation device via a detachable fluidic interface.

[0077] FIG. 7 shows the sample separation system of FIG. 6 in another switching state of a modulator valve thereof.

[0078] FIG. 8 shows a portion of a secondary state sample separation device according to an exemplary embodiment in which a modulator valve is in fluid connection with a buffer valve in fluid connection with a plurality of buffer volumes in each of which a respective fluid packet coming from a primary stage sample separation device can be buffered.

[0079] FIG. 9 shows a portion of a secondary stage sample separation device according to an exemplary embodiment in which a modulator valve cooperates with two buffer valves each cooperating with a plurality of buffer volumes for temporarily storing a respective fluid packet.

[0080] FIG. 10 shows a pump of a secondary stage sample separation device according to an exemplary embodiment which allows to define and adapt a flow rate value of fluid flowing through the secondary stage sample separation device.

[0081] FIG. 11 to FIG. 14 illustrate parts of two-dimensional sample separation systems according to exemplary embodiments of the invention and having different embodiments of pressure reduction mechanisms.

[0082] The illustration in the drawing is schematic.

[0083] Before, referring to the drawings, exemplary embodiments will be described in further detail, some basic considerations will be summarized based on which exemplary embodiments of the invention have been developed.

[0084] According to an exemplary embodiment of the invention, a two-dimensional liquid chromatography system (2D-LC) with suppression of a back pressure pulse in the first dimension is provided.

[0085] In 2D-LC, the effluate of the first dimension separation is portion-wise introduced into the second dimension by a modulation unit, typically a modulator valve (also denoted as injector valve), which directs the effluate flow into a modulation loop (also denoted as buffer volume), typically by alternatingly switching between two or more modulation loops (which may also be denoted as buffer volumes). Such flow redirection operations can be accompanied by a temporary flow path interruption. The flow rate in the first dimension is typically low and the system elasticity is high, thus it may be believed that the pressure alteration during a very short flow interruption will not be significant. This is in particular true for the pump outlet pressure on the first-dimension pump, which alters insignificantly. However, the post-column pressure alters strongly, reaching nearly the column inlet pressure within several milliseconds due to extreme system rigidity flow downstream of the column. In particular once a detector is included into the first dimension set-up (which is frequently desired or necessary), these pressure pulses can be harmful for data acquisition, causing artifacts at the base line, or even cause hardware damage to the detection cell or the column.

[0086] According to an exemplary embodiment of the invention, a pressure reduction mechanism (in particular a pressure reduction device) for suppression of the said pressure spikes in order to avoid the described negative effects is provided. In order to suppress the pressure spikes using a pressure reduction mechanism, in particular the following embodiments are possible:

[0087] In a first embodiment (see for example FIG. 11) it is possible to introduce a pressure relief valve in the fluid path close to the detector of the first dimension, preferably between the detector of the first dimension and the modulation valve of the second dimension, in order to limit the maximum pressure which can act on the detector cell, for instance by relieving the excessive fluid (i.e. fluidic sample which may include a mobile phase such as a solvent or a solvent composition) to a waste line.

[0088] In a second embodiment (see for example FIG. 12) it is possible to introduce a flow-through elastic member of a limited volume into the flow path close to the detector of the first dimension, preferably between the detector and the modulation valve, such that the elasticity of the said elastic member can accommodate the excessive volume gathering during the flow blockage (interruption downstream), which otherwise would result in an intolerable pressure increase (typically a volume of 1 l to 3 l needs to be parked or buffered by a pressure increase of less than approximately 100 bars).

[0089] In a third embodiment (see for example FIG. 13) it is possible to introduce a flow restriction (which may also be denoted as fluid restriction) leading to waste into a side branch of the flow path close to the detector of the first dimension, such that only a little portion of the effluate can escape during the loop filling when the flow path is open, but the excessive effluate can take the flow path to the waste during the flow path blockage, without building up pressure over a safety margin, for instance of 100 bar.

[0090] In a fourth embodiment it is possible to introduce an elastic member into a side branch (an example is shown with dotted lines in FIG. 12 as well) of the flow path close to the detector of the first dimension, such that the elasticity of the said elastic member can accommodate the excessive volume gathering during the flow interruption. The elastic member may be an elastic reservoir but also a rigid reservoir of a volume, sufficient to accommodate the excessive fluid due to compressibility of the fluid within the reservoir.

[0091] In a fifth and particularly preferred embodiment (see for example FIG. 14) it is possible to introduce an elastic member as in the fourth embodiment equipped with:

[0092] a. an additional pressure relief valve, and/or

[0093] b. an additional restriction leading the fluid from the side branch to waste, so that no delayed material exchange back from the elastic side branch into the main flow path can take place (delayed material exchange is for instance diffusion of the content of the side branch after the pressure pulse has passed), and/or

[0094] c. a check valve on the inlet terminus of the said side elastic branch especially for preventing backflow.

[0095] According to an exemplary embodiment of the invention, a second dimension sample separation device (or secondary stage sample separation device) with an assigned separation unit is provided which is configured to fit perfectly to any existing first dimension sample separation device (or primary stage sample separation device) on-the-fly.

[0096] The optimization of (U)HPLC methods for chromatographic resolution gains importance when samples become increasingly complex (i.e. having plenty of compounds). Yet frequently one would encounter evidence (such as a shoulder or tail on a chromatographic peak) or it is a fear that there might be a hidden component that co-elutes in parallel to a substance of interest. An important application example for such a scenario can be found in the pharmaceutical industry: The impurity profiling workflow seeks for impurities in the active pharmaceutical ingredient (API). Impurities have to be reported down to a level of 0.05% of the API. In this case it may be a huge effort to verify. Possibilities are the re-analysis of the sample using different HPLC column media or for example to use orthogonal separation techniques, like electrophoresis. It can be very helpful if a user has a two-dimensional liquid chromatography (2D-LC) system available. Still one would have to develop and optimize a complete 2D-LC method, dedicated for this actual application or a certain application class. The result can be a dramatic loss in performance and efficiency (increased effort and longer time-to-market) due to a potential loss in analysis speed and required optimization procedures. Especial in the initial learning phase, when a user is still doing method development, a sudden unexpected result may be disturbing (at least distracting). Slightest modifications may disrupt and the effect is gone. Even if a user switches from a one-dimensional separation device to a two-dimensional separation device by using the same type of column media, a user still faces the fact that the resolution may be different and the user may have lost the track.

[0097] In order to overcome the above-mentioned shortcomings, an exemplary embodiment of the invention provides a secondary stage sample separation device that can be easily transported to aid in making the second dimension separation independent of a first (one) dimension method. For instance, an existing 1D-LC setup (as primary stage sample separation device) can be simply extended on-the-fly with a second dimension (i.e. the secondary stage sample separation device) that can be used as extension-analyzer that can automatically resolve additional features.

[0098] A secondary stage sample separation device according to an exemplary embodiment of the invention can include one of the following features: [0099] a pump operable to ensure a predefinable flow rate the second dimension (see FIG. 10) [0100] a set of columns (preferably such that show as much as possible orthogonal separation behavior) and mobile phases for scouting (see FIG. 3) [0101] several sample loops with varying volumes (see FIG. 8 and FIG. 9) [0102] capability of reading 1D-method or raw data from previous runs to align operation of the 2D extension [0103] lose trigger cable for start indication, or analog pressure synchronization [0104] inside T-piece with fluidic valve for flow calibration

[0105] According to an exemplary embodiment of the invention, a method of adding a second dimension separation (by providing a secondary stage sample separation device) to a running conventional system (i.e. the primary stage sample separation device) is provided, without a need to modify any hardware, software, firmware components or programmed methods of the existing system (i.e. of the primary stage sample separation device).

[0106] According to another exemplary embodiment of the invention, a second dimension subsystem (i.e. the secondary stage sample separation device) is provided, which can be attached to the outlet of an existing system (i.e. the primary stage sample separation device) to analyze the effluent in the second dimension. The subsystem can be compact, transportable, capable of being operated independently of the first dimension, whereas its operation may be synchronized (in particular as slave) to the first dimension at certain reference points. The subsystem may bear accessory means providing extended independence (for instance a flow splitter, an active flow splitter, a pump as shown in FIG. 10 which is capable of defining a desired flow rate, an independent system controller, etc.) and extended flexibility (such as a variable modulation loop appliance, a column and mobile phase scouting hardware, etc.).

[0107] In an embodiment, when connected to the outlet of an existing 2D-LC setup (as primary stage sample separation device), then the above described cart (as secondary stage sample separation device) actually forms the third dimension.

[0108] FIG. 1 illustrates a two-dimensional sample separation system 100 according to an exemplary embodiment of the invention.

[0109] The sample separation system 100 is constituted by a spatially static primary stage sample separation device 10 and a movable or mobile secondary stage sample separation device 90. They are flexibly and detachably connected to one another mechanically and fluidically via a waste conduit 58 of the primary stage sample separation device 10 and via a fluidic interface 89 of the secondary stage sample separation device 90. In the shown embodiment, the fluidic interface 89 can be a snap-fit connector. For accomplishing the fluidic and mechanical coupling of the primary stage sample separation device 10 and the secondary stage sample separation device 90 according to FIG. 1, the secondary stage sample separation device 90 can be moved towards the static primary sample separation device 10 and can be fluidically coupled in a detachable manner to the primary stage sample separation device 10 via the fluidic interface 89. The secondary stage sample separation device 90 may be movable by a user by driving the secondary sample separation device 90 using a cart 86. The cart 86 has a support and has wheels, wherein the various fluidic members of the secondary stage sample separation device 90 are mounted on the support and can be moved making use of the wheels of the cart 86. Thus, by coupling the secondary stage sample separation device 90 to the primary stage sample separation device 10, it is possible to temporarily establish two-dimensional sample separation system 100. Since the fluidic interface 89 can be a multipurpose fluidic interface, flexible combination of the secondary stage sample separation device 90 with one of different primary stage sample separation devices 10 is possible. The secondary stage sample separation device 90 is configured as to conform the flow rates between the two stages at the fluidic interface 89 in a self-sufficient way and without the necessity of involving a user.

[0110] The secondary stage sample separation device 90 is configured for further separating fractions of the fluidic sample into sub-fractions, which fractions are provided by the primary stage sample separation device 10 as a result of the initial separation of the fluidic sample. As will be described below in further detail, the sample separation system 100 is configured for carrying out two-dimensional liquid chromatography separation (2D-LC) of a fluidic sample.

[0111] As can be taken from FIG. 1, an optional secondary stage pressure reduction mechanism 44 is provided in the secondary stage sample separation device 90 and is configured for reducing pressure at the fluidic interface 89 and upstream thereof (i.e. in the primary stage sample separation device 10) in the event of an overpressure. It is additionally or alternatively also possible to provide an optional primary stage pressure reduction mechanism 45 in the primary stage sample separation device 10 which is configured for reducing pressure in the primary stage sample separation device 10 in the event of an overpressure in the secondary stage sample separation device 90. Any of these pressure reduction mechanisms 44, 45 is capable of preventing an overpressure (which may be generated temporarily during switching of the secondary stage injector valve or modulator valve 98) from impacting the detector 50 of the primary stage sample separation device 10. Any of these pressure reduction mechanisms 44, 45 may be configured for instance in accordance with any of the embodiments of FIG. 11 to FIG. 14.

[0112] Next, the operation of the primary stage sample separation device 10 will be explained. This operation can be a standalone operation, i.e. the primary stage sample separation device 10 may be operated completely independent of the optionally and flexibly connectable secondary stage sample separation device 90 when a single stage separation is sufficient. In such a standalone one-dimensional separation mode, waste conduit 58 is guided into a waste container 60 in which the separated fluidic sample is accumulated. In an extended two-dimensional separation mode as shown in FIG. 1, the waste conduit 58 is mechanically and fluidically connected to the fluidic interface 89, as indicated schematically by reference numeral 21 in FIG. 1.

[0113] When taken alone, the primary stage sample separation device 10 operates as a one dimensional liquid separation system, as follows: A first pump 20 receives a mobile phase as a whole or as individual components that get mixed together by the first pump 20, from a first solvent supply 25, typically via a first degasser 27, which degases and thus reduces the amount of dissolved gases in the mobile phase. The first pump 20as a mobile phase drivedrives the mobile phase through a first separating unit 30 (such as a chromatographic column) comprising a stationary phase. A first sampling unit 40 can be provided between the first pump 20 and the first separating unit 30 in order to subject or add (often referred to as sample introduction) a sample fluid (also denoted as fluidic sample) into the mobile phase. Switching of a fluidic valve 80 actually triggers the injection. The stationary phase of the first separating unit 30 is configured for separating compounds of the sample liquid. After detection of the separated fluidic sample by a first detector 50, the separated fluidic sample is further transported via waste conduit 58 and is then accumulated in the waste container 60.

[0114] A data processing unit 70, which can be a conventional PC or workstation, might be coupled (as indicated by the dotted arrows) to one or more of the devices in the primary stage sample separation device 10 in order to receive information and/or control operation. For example, the data processing unit 70 might control operation of the first pump 20 (for instance setting control parameters) and receive therefrom information regarding the actual working conditions (such as output pressure, flow rate, etc.). The data processing unit 70 might also control operation of the first solvent supply 25 (for instance setting the solvent/s or solvent mixture to be supplied) and/or the first degasser 27 (for instance setting control parameters such as vacuum level) and might receive therefrom information regarding the actual working conditions (such as solvent composition supplied over time, flow rate, vacuum level, etc.). The data processing unit 70 might further control operation of the first sampling unit 40 (for instance controlling sample injection or synchronization sample injection with operating conditions of the first pump 20). The first separating unit 30 might also be controlled by the data processing unit 70 (for instance selecting a specific flow path or column, setting operation temperature, etc.), and sendin returninformation (for instance operating conditions) to the data processing unit 70. Accordingly, the first detector 50 might be controlled by the data processing unit 70 (for instance with respect to spectral or wavelength settings, setting time constants, start/stop data acquisition), and send information (for instance about the detected sample compounds) to the data processing unit 70.

[0115] In contrast to the primary stage sample separation device 10, the secondary stage sample separation device 90 is not intended to be operated as a standalone device. In contrast to this, operation of the secondary stage sample separation device 90 in terms of sample separation requires mechanical and fluidic connection between the primary stage sample separation device 10 and the secondary sample separation device 90 via the fluidic interface 89, as shown in FIG. 1. When a user wants to extend the one-dimensional separation capability of the primary stage sample separation device 10, the user may detachably fluidically connect the fluidic interface 89 of the secondary stage sample separation device 90 to waste line 58 of the primary stage sample separation device 10.

[0116] In the coupled state as shown in FIG. 1, fluidic sample separated by the primary stage sample separation device 10 into fractions is fluidically supplied to the secondary stage sample separation device 90 for further separation of the fractions into sub-fractions. Advantageously, as will be described below in further detail, the secondary stage sample separation device 90 is configured for further separating the supplied fluidic sample independent or irrespective of a flow rate value of the fluidic sample supplied from the primary stage sample separation device 10 at the fluidic interface 89. Hence, a flow rate adaptation between the given flow rate of the primary stage sample separation device 10 and the adjustable flow rate taken up in the secondary sample separation device 90 is possible by means of a flow rate adapter 88. The latter is configured for performing an adaptation between the flow rate of the fluidic sample supplied by the primary stage sample separation device 10 and a flow rate according to which the secondary stage sample separation device 90 is configured to operate with.

[0117] As can be taken from FIG. 1, the fluid coming from the primary stage sample separation device 10, after adaptation of the flow rate of the two stages by the flow rate adapter 88, is injected via a modulator valve 98 into an analytic path of the secondary sample separation device 90. Mobile phase is provided by a second solvent supply 82. The provided mobile phase can be degassed in a second degasser 84 and can be pumped by a second pump 92 of the secondary stage. At the modulator valve 98, the mobile phase is mixed with a fluid packet originating from the primary stage sample separation device 10. This fluid packet which may include one or more fractions of the fluidic sample is then further separated by liquid chromatography in a second separation unit 93, in particular a further chromatographic column, into sub-fractions. The separated sub-fractions, which can be desorbed from the second separation unit 93 by applying a mobile phase gradient can be detected in a second detector 95. If not a distructive detector (such as a mass spectrometer), the separated sub-fractions can be guided towards a second waste container 96 (alternatively a fraction collector). A second processor 97 of the secondary stage sample separation device 90 is configured for controlling only the secondary separation and does not cooperate with processor 70 of the primary stage sample separation device 10, so that both stages are controlled by a separate independently operating processor 70, 97 or processing routine.

[0118] FIG. 2 illustrates a three-dimensional view of a mobile secondary stage sample separation device 90 mounted on a cart 86 according to an exemplary embodiment of the invention. The individual fluidic components of the secondary stage sample separation device 90 are mounted on the card 86 as modules. A fluidic and mechanical connection to a primary stage sample separation device 10 (not shown) can be accomplished by a user by simply plugging fluidic interface 89 together with a free or open end of a waste conduit 58. A user interface 200, shown as a display, is provided as well which allows unidirectional or bidirectional communication between a user and the secondary stage sample separation device 90.

[0119] FIG. 3 shows a detailed view of a secondary stage sample separation device 90 according to an exemplary embodiment of the invention.

[0120] Downstream of the fluidic interface 89, the fluidic sample arriving from the primary stage sample separation device 10 (not shown in FIG. 3) can be redetected by an interface detector 308. More specifically, interface detector 308 is configured for redetecting the fluidic sample separated by the primary stage sample separation device 10 prior to the further separation of the fluidic sample by the secondary stage sample separation device 90. Knowledge of the way as to how fractions of the fluidic sample have been separated by the primary stage sample separation device 10 and as to how they arrive at the fluidic interface 89 allows the secondary stage sample separation device 90 to adjust its own operation parameters for the secondary separation synchronized to the primary separation. The interface detector 308 may in particular detect a reference peak expected from the primary stage so as to adapt timing of the secondary stage to a given separation timing of the primary stage.

[0121] At a fluidic T-piece 350 downstream of the interface detector 308, a part of the fluidic sample may be guided via a fluid restrictor 352 towards a waste 360, whereas another part (i.e. the rest) of the fluidic sample is guided towards a modulator valve 98. By configuring the fluid restrictor 352 to have an adjustable fluidic impedance or resistance, the individual amounts propagating towards waste 360 and towards modulator valve 98 can be adjusted in terms of flow rate adjustment between the two stages.

[0122] The modulator valve 98 is switchable under control of the control unit 97 (not shown in FIG. 3) so that, consecutively, individual fluid packets of the fluidic sample arriving from the primary stage and passing the fluidic T-piece 350 towards the modulator valve 98 can be injected into an analytical path of the secondary stage.

[0123] However, the analytical path is, according to FIG. 3, selectable. As can be taken from FIG. 3, one of three partially parallel flow paths 302 between the analytical pump 92 and one of a plurality of separation units 93 (for instance chromatographic columns of different dimensions and/or different separation characteristics) can be selected by correspondingly switching a selection valve 354 (which can be switched under control of the control unit 97). Thus, in dependence of the flow rate of the primary stage and/or in dependence or a required/selected separation characteristic, an appropriate one of the individual flow paths 302, each having a different dimension and therefore supporting a respective other flow rate, can be selected.

[0124] Furthermore, adaptation of the flow rate between the two stages is also possible by switching the modulator valve 98 in such a manner that individual fluid packets originating from the primary stage can be buffered temporarily in one of a plurality of buffer volumes 300, configured as separate sample loops. Moreover, a flow rate measurement unit 306 may be provided for measuring a flow rate in the secondary stage sample separation device 90. The modulator valve 98 may be controlled to switch in accordance with a measured flow rate so as to consecutively forward a predefined amount of the fluidic sample for further separation with each switch. Hence, the flow rate measurement unit 306 may measure the flow rate and may supply measurement data to the processor 97 so as to control the flow rate adaptation. Thus, the fluid packets may be supplied packet-wise for further separation by firstly buffering them in one of the buffer volumes 300, and by an appropriately timed switching of the modulator valve 98 so that a new fluidic packet is only injected into one of the analytical paths when appropriate.

[0125] As can be taken from a detail 380 in FIG. 3, as an alternative to the integration of the individual buffer volumes 300 or sample loops in the modulator valve 98, a plurality of buffer volumes 300 may be also provided separately from the modulator valve 98. It is possible to dimension the accommodation volumes of the buffer volumes 300 identical. It is however also possible to dimension them differently so as to obtain sample loops of varying accommodation volume.

[0126] It can be furthermore taken from FIG. 3 that a further possibility of adapting the flow rates of the two stages to one another is the provision of a schematically illustrated flow rate adaptation pump 370 (for instance of the type shown in FIG. 10) which is operable so that only a desired flow rate is allowed to flow through the fluidic interface of the secondary stage.

[0127] FIG. 4 illustrates a one dimensional detection chromatogram 410 of a primary stage sample separation device 10 presently operating as a standalone device. FIG. 5, in addition to one dimensional chromatograms 410 and zooms thereof, illustrates a two-dimensional detection chromatogram 510 of a sample separation system 100 according to an exemplary embodiment of the invention constituted by the primary stage sample separation device 10 according to FIG. 4 and a secondary stage sample separation device 90 according to an exemplary embodiment of the invention detachably connected to the primary stage sample separation device 10. More specifically, FIG. 4 illustrates a diagram 400 having an abscissa 402 along which a retention time (or a retention volume) is plotted, and having an ordinate 404, along which a detection signal of a chromatographic experiment is plotted. It can be seen that a peak region 420 indeed has several sub-peaks 412, 414, 416, which can be distinguished by a secondary stage separation as shown in FIG. 5 , which illustrates the result of the second dimension analysis, compare additional diagram 500.

[0128] FIG. 4 and FIG. 5 in particular illustrate the independence of the second dimension when using a 2D-cart architecture by adding a secondary stage sample separation device 90 to a primary stage sample separation device 10. FIG. 4 illustrates a one dimensional chromatogram 410, specifically the zoom or peak portion 420, (Width, W=0.5 min) showing the co-eluting peaks 412, 414, 416. As can be taken from FIG. 5, the one dimensional setup is extended using a 2D-cart including adaptation pump 370 which defines a flow rate in a flow path, whose flow is set to a predefinable value (for instance 50 L/min) that allows to fill a split portion of the peak portion 420 into a 40 L loop 520 in a quantitative manner without having to lower the flow rate in the first dimension. The flow rate of the first dimension continues to be 480 L/min, which makes the volume of the peak region 420 about 240 L.

[0129] FIG. 6 illustrates a two-dimensional sample separation system 100 according to an exemplary embodiment of the invention constituted by a primary stage sample separation device 10 and a secondary stage sample separation device 90 flexibly and detachably connected to the primary stage sample separation device 10 via a detachable fluidic interface 89. FIG. 7 shows the sample separation system 10 of FIG. 6 in another switching state of a modulator valve 98 thereof.

[0130] As can be taken from FIG. 6 and FIG. 7, the modulator valve 98 has in this case two buffer volumes 300, 301 connected to various ports thereof so that fluid packets originating from the primary stage can be buffered in the buffer volumes 300, 301 before being supplied to the analytical path of the secondary stage, i.e. between second pump 92 and second separation unit 93. In the switching state of the modulator valve 98 according to FIG. 6, the buffer volume 300 on the upper right-hand side is presently filled with new fluidic sample flowing from the first dimension into the second dimension, whereas the other buffer volume 301 on the lower left-hand side is presently in the fluidic path between the second pump 92 and the second separation unit 93, i.e. fluidic sample previously stored in this other buffer volume 301 is presently further separated. In the switching state of the modulator valve 98 according to FIG. 7, the buffer volume 301 on the lower left-hand side is presently filled with new fluidic sample flowing from the first dimension into the second dimension, whereas the buffer volume 300 on the upper right-hand side is presently in the fluidic path between the second pump 92 and the second separation unit 93, i.e. fluidic sample previously stored in this buffer volume 300 is presently further separated.

[0131] FIG. 8 shows a portion of a secondary stage sample separation device 90 according to an exemplary embodiment in which modulator valve 98 is in fluid connection with a buffer valve 800 in fluid connection with a plurality of buffer volumes 301 in each of which a respective fluid packet coming from a primary stage sample separation device 10 can be buffered. FIG. 8 shows the modulator valve 98 with buffer valve 800 which can serve in this case six buffer volumes 301 (see numbers 1 to 6 at the buffer valve 800). The switching state according to FIG. 8 corresponds to the switching state according to FIG. 6. The modulator valve 98 further cooperates with the buffer valve 800, which is in direct fluid connection with the individual buffer volumes 301 so that the fluid packets can be temporarily stored in a respectively free one of the buffer volumes 301 and can be subsequently switched individually and one after the other into the analytical path of the secondary stage.

[0132] FIG. 9 shows a portion of a secondary stage sample separation device 90 according to an exemplary embodiment in which modulator valve 98 cooperates with two buffer valves 800, 900 each cooperating with a plurality of buffer volumes 300, 301 for temporarily storing a respective fluid packet. FIG. 9 hence shows an alternative configuration in which one modulator valve 98 cooperates with two packet parking valves 800, 900. Each of the packet parking valves 800, 900 serves six buffer volumes 300, 301 (see numbers 1 to 6 at the buffer valves 800, 900). Hence, any desired number of buffer volumes 300, 301 can be implemented following the principle of FIG. 8 and FIG. 9, so that basically any adaptation of a larger flow rate of the primary stage as compared to a smaller flow rate of the secondary stage is possible.

[0133] FIG. 10 shows a flow rate adaptation pump 370 of a secondary stage sample separation device 90 according to an exemplary embodiment which allows to adapt to a flow rate value of fluid flowing through the fluidic interface 89 of the secondary stage sample separation device 90 by defining the flow rate passing through T-piece 350 towards modulator valve 98. Details of a possible construction of the flow rate adaptation pump 370 are disclosed in GB 2,490,673, which is hereby incorporated by reference in its entirety (see in particular FIG. 5A to FIG. 5F thereof).

[0134] The flow rate adaptation pump 370 is operable so that only a desired flow rate is allowed to flow through the fluidic interface 89 of the secondary stage. In particular, a flow rate between a fluid inlet 1002 and a fluid outlet 1004 can be adjusted by the flow rate adaptation pump 370 under control of the control unit 97. The fluid with the adjustable flow rate flows via the fluid inlet 1002 through a flow rate adaptation valve 1006 and from there into a working chamber 1008 of a first piston pump 1010. A first piston 1012 reciprocates within the working chamber 1008 under control of the control unit 97. In the present scenario, the fluid flows into the working chamber 1008 with a flow rate which is defined by the motion pattern of the first piston 1012. Thus, the velocity according to which the first piston 1012 moves within the first working chamber 1008 under control of the control unit 97 defines the allowed flow rate at this moment. When the first piston 1012 has moved within the first working chamber 1008 up towards an end position in which it is not capable of receiving any further fluid, the flow rate adaptation valve 1006 is switched by the control unit 97 so that the first working chamber 1008 can be emptied towards the fluid outlet 1004 by an inverse motion of the first piston 1012. New fluid from the fluid inlet 1002 can now be accommodated in a second working chamber 1018 of a second piston pump 1020. In the period in which the fluid has been received in the first working chamber 1008, other fluid which has been previously filled into the second working chamber 1018 of the second piston pump 1020 has been guided towards the fluid outlet 1004 by a controlled motion of a second piston 1022. During the corresponding motion of the second piston 1022, the second working chamber 1018 has been emptied. This procedure can be repeated continuously. Thus, with a coordinated switching of the flow rate adaptation valve 1006 and a corresponding control of the movement of the pistons 1012, 1022, all under control of the control unit 97, the flow rate of the fluid flowing between the fluid inlet 1002 and the fluid outlet 1004 can be precisely defined.

[0135] FIG. 11 illustrates a portion of a two-dimensional sample separation system 100 according to an exemplary embodiment of the invention and having a pressure reduction mechanism 44. The portion shown in FIG. 11 corresponds to an interface section between a primary stage sample separation device 10 and a secondary stage sample separation device 90, as shown in FIG. 1.

[0136] The secondary stage sample separation device 90 is configured for separating a fluidic sample and comprises the fluidic interface 89 configured for forming a detachable fluidic coupling between the primary stage sample separation device 10 and the secondary stage sample separation device 90 so that the fluidic sample separated by the primary stage sample separation device 10 and detected by detector 50 of the first stage is fluidically supplied to the secondary stage sample separation device 90 via the fluidic interface 89 for further separation. Pressure reduction mechanism 44 is configured for reducing pressure at the fluidic interface 89 in the event of an overpressure in the secondary stage sample separation 90. The pressure reduction mechanism 44 is configured for negatively preventing the overpressure from impacting the primary stage sample separation device 10, in particular the detector 50. The pressure reduction mechanism 44 is in particular configured for reducing pressure at the fluidic interface 89 in the event of an overpressure generated by a switching operation of modulator valve 98 of the secondary stage sample separation device 90. An overpressure event is generated by a temporary incapability or reduced capability of the secondary stage sample separation device 90 to accept and further process fluidic sample material from the primary stage sample separation device 10. The pressure reduction mechanism 44 can accommodate or accept fluidic sample material selectively in the event of a temporary incapability or reduced capability of the secondary stage sample separation device 90 to receive fluidic sample material from the primary stage sample separation device 10. The pressure reduction mechanism 44 protects primary stage sample separation device 10 from pumping fluidic sample material against a temporarily fluidically blocking secondary stage sample separation device 90 and offers an alternative flow channel for excessive pressure reduction. In FIG. 11, the pressure reduction mechanism 44 is arranged downstream of the fluidic interface 89 and upstream of a modulator valve 98 of the secondary stage sample separation device 90.

[0137] In the embodiment of FIG. 11, the pressure reduction mechanism 44 comprises a pressure relief valve 1100 arranged between the fluidic interface 89 and the modulator valve 98 of the secondary stage sample separation device 90. The pressure relief valve 1100 is arranged and configured to disable flow of fluidic sample apart from a fluidic path 1110 between the fluidic interface 89 and the modulator valve 98 in the absence of overpressure (or to enable flow of fluidic sample only between the fluidic interface 89 and the modulator valve 98 in the absence of overpressure), and to split off flow of fluidic sample through the pressure relief valve 1100 away from the fluidic path 1110 between the fluidic interface 89 and the modulator valve 98 in the event of an overpressure. The pressure relief valve 1100 is here embodied as a spring biased ball valve, wherein the ball is denoted with reference numeral 1130 and the biasing spring is denoted with reference numeral 1140.

[0138] Operation of the pressure reduction mechanism 44 is as follows:

[0139] When fluidic sample is supplied from the primary stage sample separation device 10 to the secondary stage sample separation device 90, consecutive fluid packets are processed by a corresponding switching sequence of the modulator valve 98. In a first operation mode, a fluid packet of the fluidic sample is delivered via a fluidic path A.fwdarw.B.fwdarw.F, while simultaneously a previously supplied fluid packet of the fluidic sample is forwarded via a fluidic path D.fwdarw.C.fwdarw.E (compare also FIG. 6). Terminal A connects the modulator valve 98 to the fluidic sample delivered from the primary stage sample separation device 10. B relates to the upper one of the buffer volumes 300 according to FIG. 11. C relates to the lower one of the buffer volumes 300 according to FIG. 11. Terminal D is connected to a high pressure pump of the secondary stage sample separation device 90. Terminal E connects to a sample separation unit of the secondary stage sample separation device 90. Terminal F connects to waste 58. After switching the modulator valve 98 into a second operation mode (compare also FIG. 7), a subsequent fluid packet of the fluidic sample is delivered via a fluidic path A.fwdarw.C.fwdarw.F, while simultaneously the previously supplied fluid packet of the fluidic sample is forwarded via a fluidic path D.fwdarw.B.fwdarw.E for further separation. During each switching procedure of the modulator valve 98, there is a certain time interval (for instance having a duration in a range between 50 ms and 700 ms) during which the secondary stage sample separation device 90 is incapable of accepting new fluidic sample from the primary stage sample separation device 10 (which continues to pump such new fluidic sample). This may result in an overpressure. The pressure relief valve 1100 then opens and splits off fluidic sample into a side path 1120 branching off from fluidic path 1110 and being connected to drain or waste 58. This again reduces the overpressure and prevents in particular the sensitive detector 50 of the primary stage sample separation device 10 from damage.

[0140] FIG. 12 illustrates a two-dimensional sample separation system 100 according to another exemplary embodiment of the invention and having a pressure reduction mechanism 44 as well.

[0141] The difference between the embodiment of FIG. 11 and the embodiment of FIG. 12 is that according to FIG. 12 the pressure reduction mechanism 44 comprises an elastic member 1200 (rather than a pressure relief valve 1100) being elastically expandable in the event of an overpressure to thereby temporarily accommodate fluidic sample material for reducing pressure. The elastic member 1200 is configured as a flow-through member arranged in the fluidic conduit 1110 between the fluidic interface 89 and the modulator valve 98.

[0142] Additionally or alternatively to the arrangement of the elastic member 1200 as just described, and as indicated with dotted lines in FIG. 12, the above-mentioned elastic member 1200 or an additional elastic member 1200 may be arranged in side path 1120 with regard to fluidic conduit 1110 between the fluidic interface 89 and the modulator valve 98 to split off fluidic sample into the side path 1120 through the elastic member 1200 away from the fluidic path 1110 between the fluidic interface 89 and the modulator valve 98 in the event of an overpressure.

[0143] FIG. 13 illustrates a two-dimensional sample separation system 100 according to another exemplary embodiment of the invention and having yet another pressure reduction mechanism 44.

[0144] The difference between the embodiment of FIG. 11 and the embodiment of FIG. 13 is that according to FIG. 13 the pressure reduction mechanism 44 comprises a flow restrictor or fluid restrictor 1300 (rather than a pressure relief valve 1100) having a higher fluidic impedance than and being in fluid communication with the fluidic conduit 1110 between the fluidic interface 89 and the modulator valve 98. The fluid restrictor 1300 is arranged in side path 1120 which is branched off from the fluidic conduit 1110 between the fluidic interface 89 and the modulator valve 98 to thereby branch off fluidic sample material in the event of an overpressure. The fluid restrictor 1300 is connected to waste 58 so as to prevent any possibility of fluid blockade.

[0145] FIG. 14 illustrates a two-dimensional sample separation system 100 according to still another exemplary embodiment of the invention and having a combined pressure reduction mechanism 44. The embodiment of FIG. 14 synergetically combines individual pressure reduction mechanisms 44 shown in FIG. 11, FIG. 12 and FIG. 13.

[0146] According to FIG. 14, the pressure reduction mechanism 44 comprises a pressure relief valve 1100 having the above mentioned features, an elastic member 1200 which is here configured as an elastic capillary portion within side path 1120, and a fluid restrictor 1300 having the above mentioned features. The pressure reduction mechanism 44 is implemented in or forming part of side path 1120 or side branch branching off from fluidic conduit 1110 between the fluidic interface 89 and the modulator valve 98. The side path 1120 hence comprises redundant pressure reduction members 1200, 1100, 1300. More specifically, the pressure reduction mechanism 44 in the side path 1120 or branch comprises a fluidic serial connection of a first pressure reduction stage embodied as the elastic member 1200 and a second pressure reduction stage downstream (in accordance with a fluid flow direction in the event of an overpressure) of the first pressure reduction stage and configured as a pressure relief valve 1100 coupled to waste 58 both directly at a first valve interface (i.e. adjacent biasing spring 1140) and additionally indirectly at another valve interface (i.e. adjacent ball 1130) via fluidic restrictor 1300.

[0147] In the event of an overpressure, the overpressure is firstly reduced by an expansion of the elastic member 1200 (and/or by compressing of the content therein). Fluidic sample flows through the expanding or inflating elastic member 1200, passes the pressure relief valve 1100 and flows into fluidic resistor 1300 towards waste 58. In the described operation mode, the pressure relief valve 1100 is still inactive. Only in an emergency scenario in which cooperation of elastic member 1200 and fluidic resistor 1300 is still incapable of reducing the overpressure to a sufficient extent, the pressure relief valve 1100 will be activated so as to direct fluidic sample through an additional flow path towards waste 58, similar as in FIG. 11. Therefore, only in very rare cases, the pressure relief valve 1100 needs to become active. Thus, the pressure relief valve 1100 is usually not required to drive back into a normally closed state when overpressure has been reduced again. Such a drive back procedure may be less reliable than the deactivation of cooperating elastic member 1200 and fluidic resistor 1300. However, at the same time, the high overpressure reduction capability of the pressure relief valve 1100 may still be used in an emergency case. Even more preferably, the through flow architecture according to FIG. 14 prevents any fluidic sample from accumulating in narrow sections of the side path 1120 so that an efficient protection against carryover is provided as well.

[0148] Moreover, the following aspects are disclosed in terms of exemplary embodiments of the invention: [0149] Aspect 1: A secondary stage sample separation device (90) for separating at least a portion of a fluidic sample, wherein the secondary stage sample separation device (90) comprises: [0150] a fluidic interface (89) configured for forming a detachable fluidic coupling between a primary stage sample separation device (10) and the secondary separation device (90) so that the fluidic sample separated by the primary stage sample separation device (10) is fluidically suppliable to the secondary stage sample separation device (90) via the fluidic interface (89) for further separation; [0151] wherein the secondary stage sample separation device (90) is further configured for separating at least a portion of the supplied fluidic sample independent of a flow rate of the fluidic sample supplied from the primary stage sample separation device (10) at the fluidic interface (89). [0152] Aspect 2: The secondary stage sample separation device (90) according to aspect 1, comprising a flow rate adapter (88, 352, 370, 98) configured for performing an adaptation between the flow rate of the fluidic sample supplied by the primary stage sample separation device (10) and a flow rate, in particular a smaller flow rate, according to which the secondary stage sample separation device (90) is configured to operate with. [0153] Aspect 3: The secondary stage sample separation device (90) according to aspect 2, wherein the flow rate adapter (88, 352, 370, 98) is configured for performing the adaptation by splitting the fluidic sample supplied to the secondary stage sample separation device (90) into a first flow path corresponding to the flow rate acceptable by the secondary stage sample separation device (90) and used for further separation of at least a portion of the fluidic sample, and into a second flow path, in particular being drained to waste. [0154] Aspect 4: The secondary stage sample separation device (90) according to aspect 2 or 3, wherein the flow rate adapter (88, 352, 370, 98) is configured for performing the adaptation by buffering consecutive portions of the fluidic sample supplied by the primary stage sample separation device (10) into a plurality of buffer volumes (300, 301), in particular sample loops, and for consecutively forwarding the buffered portions of the fluidic sample in the various buffer volumes (300, 301) for the further separation. [0155] Aspect 5: The secondary stage sample separation device (90) according to any of aspects 2 to 4, wherein the flow rate adapter (88, 352, 370, 98) is configured for performing the adaptation by defining a flow rate to one or a plurality of buffer volumes (300, 301), in a particular way, so as to park a specific representative portion of the fluidic sample relating to a region of interest (420) in a separation spectrum, in particular in a chromatogram, for consecutively forwarding this buffered portion as the fluidic sample for the further separation. [0156] Aspect 6: The secondary stage sample separation device (90) according to any of aspects 2 to 5, wherein the flow rate adapter (88, 352, 370, 98) is configured for performing the adaptation by guiding at least a portion of the fluidic sample provided by the primary stage sample separation device (10) into a selected one of a plurality of sample separation paths (302) in the secondary stage sample separation device (90), each of the sample separation paths (302) being operable in accordance with an assigned flow rate, so as to obtain a best match between the flow rate of the primary stage sample separation device (10) with a corresponding flow rate assigned to the selected one of the multiple sample separation paths (302). [0157] Aspect 7: The secondary stage sample separation device (90) according to any of aspects 2 to 6, wherein the flow rate adapter (88, 352, 370, 98) comprises a modulator valve (98) and a flow rate measurement unit (306) for measuring a flow rate in the secondary stage sample separation device (90), wherein the modulator valve (98) is controlled to switch in accordance with a measured flow rate so as to consecutively forward a predefined amount of the fluidic sample for further separation with each switch. [0158] Aspect 8: The secondary stage sample separation device (90) according to any of aspects 1 to 7, wherein the fluidic interface (89) is configured for being fluidically coupled to a waste conduit (58) of the primary stage sample separation device (10). [0159] Aspect 9: The secondary stage sample separation device (90) according to any of aspects 1 to 8, configured as a mobile secondary stage sample separation device (90), in particular as at least one of the group consisting of a transportable, a physically mobile, a roll-comprising, and a rollable secondary stage sample separation device (90). [0160] Aspect 10: The secondary stage sample separation device (90) according to any of aspects 1 to 9, comprising a cart (86), in particular having at least one wheel, by which the secondary stage sample separation device (90) is movable, in particular by rolling, by a user. [0161] Aspect 11: The secondary stage sample separation device (90) according to any of aspects 1 to 10, comprising a processor (97) configured for controlling the further sample separation by the secondary stage sample separation device (90) without controlling operation of the sample separation by the primary stage sample separation device (10). [0162] Aspect 12: The secondary stage sample separation device (90) according to aspect 11, wherein the processor (97) is configured for synchronizing the secondary stage sample separation device (90) with the primary stage sample separation device (10) based on a predefined reference peak resulting from the sample separation by the primary stage sample separation device (10). [0163] Aspect 13: The secondary stage sample separation device (90) according to any of aspects 1 to 12, comprising at least one of the following features: [0164] the secondary stage sample separation device (90) is configured for receiving data indicative of the sample separation by the primary stage sample separation device (10) and is configured for adapting the further sample separation by the secondary stage sample separation device (90) in accordance with the received data; [0165] the secondary stage sample separation device (90) comprises an interface detector (308, 310) at the fluidic interface (89) configured for redetecting the fluidic sample separated by the primary stage sample separation device (10), in particular prior to the further separation of at least a portion of the fluidic sample by the secondary stage sample separation device (90); [0166] the fluidic interface (89) is configured as one of the group consisting of a snap-fit connector, a fitting piece, in particular a male fitting piece or a female fitting piece, a lever-based connector, a bayonet connector and a screw connector. [0167] Aspect 14: The secondary stage sample separation device (90) according to any of aspects 1 to 13, comprising a modulator valve (98) configured for dividing the fluidic sample supplied by the primary stage sample separation device (10) into a plurality of consecutive fluid packets and for consecutively guiding individual ones of the fluid packets into an analytical path of the secondary stage sample separation device (90) in which at least a part of the fluid packets of the fluidic sample are to be further separated. [0168] Aspect 15: The secondary stage sample separation device (90) according to aspect 14, comprising at least one of the following features: [0169] the analytical path comprises an analytical pump (84) for pumping mobile phase to be mixed with the fluid packets and comprises a sample separation unit (93) for further separating the fluidic sample in the mixture; [0170] the modulator valve (98) comprises a plurality of buffer volumes (300, 301), in particular sample loops, each for buffering a corresponding one of the fluid packets; [0171] the secondary stage sample separation device (90) comprises a plurality of buffer volumes (300, 301), in particular sample loops, each for buffering a corresponding one of the fluid packets, wherein the buffer volumes (300, 301) are provided separately from the modulator valve (98) and fluidically coupled to the modulator valve (98). [0172] Aspect 16: The secondary stage sample separation device (90) according to any of aspects 1 to 15, wherein the secondary stage sample separation device (90) is configured as one of the group consisting of: [0173] a chromatography sample separation device, in particular a liquid chromatography sample separation device, a gas chromatography sample separation device or a supercritical fluid chromatography sample separation device; and [0174] an electrophoresis sample separation device, in particular a capillary electrophoresis sample separation device. [0175] Aspect 17: A sample separation system (100) for carrying out a multiple stage separation of a fluidic sample, wherein the sample separation system (100) comprises: [0176] a primary stage sample separation device (10) for separating a fluidic sample; [0177] a secondary stage sample separation device (90) according to any of aspects 1 to 16 detachably fluidically couplable to the primary stage sample separation device (10) via the fluidic interface (89) and configured for separating at least a portion of the fluidic sample supplied and separated by the primary stage sample separation device (10). [0178] Aspect 18: The sample separation system (100) according to aspect 17, comprising at least one of the following features: [0179] the primary stage sample separation device (10) is static; [0180] the secondary stage sample separation device (90) is mobile; [0181] the sample separation system further comprises at least one further, in particular static, primary stage sample separation device (10) configured for being alternatively fluidically coupleable to the secondary stage sample separation device (90) via the fluidic interface (89); [0182] the primary stage sample separation device (10) is a multiple stage sample separation device; [0183] the primary stage sample separation device (10) is configured as one of the group consisting of a chromatography sample separation device, in particular a liquid chromatography sample separation device, a gas chromatography sample separation device or a supercritical fluid chromatography sample separation device, and an electrophoresis sample separation device, in particular a capillary electrophoresis sample separation device; [0184] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises a pump (20, 92) configured for driving a mobile phase and the fluidic sample in the mobile phase; [0185] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises a separation unit (30, 93) configured for separating at least a portion of the fluidic sample; [0186] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises an injector (40, 98) configured for injecting the fluidic sample into the mobile phase; [0187] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises a detector (50, 95) configured to detect separated fractions of at least a portion of the fluidic sample; [0188] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises a fractioner (or fractioning) unit configured to collect separated fractions of the fluidic sample; [0189] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises a processor (70, 97) configured to process data related to the fluid separation; [0190] at least one of the primary stage sample separation device (10) and the secondary stage sample separation device (90) comprises a degassing apparatus (27, 84) for degassing mobile phase; [0191] Aspect 19: A method of carrying out a multiple stage separation of a fluidic sample, wherein the method comprises: [0192] fluidically coupling a primary stage sample separation device (10) to a secondary stage sample separation device (90), in particular a secondary stage sample separation device (90) according to any of aspects 1 to 16, by attaching a fluidic interface (89) of the secondary stage sample separation device (90) to a fluid outlet of the primary stage sample separation device (10); [0193] carrying out a primary stage separation of the fluidic sample by the primary stage sample separation device (10); [0194] carrying out a secondary stage separation of at least a portion of the fluidic sample by the secondary stage sample separation device (90) by further separating at least a portion of the separated fluidic sample provided at the fluidic interface (89); [0195] after carrying out the primary stage separation and the secondary stage separation, detaching the fluidic interface (89) from the primary stage sample separation device (10) to thereby fluidically decouple the secondary stage sample separation device (90) from the primary stage sample separation device (10). [0196] Aspect 20: The method according to aspect 19, further comprising: [0197] before the fluidically coupling, moving the secondary stage sample separation device (90), being configured as a mobile secondary stage sample separation device (90), towards the primary stage sample separation device (10), being configured as a static primary stage sample separation device (10); and [0198] after the detaching, moving the mobile secondary stage sample separation device (90) away from the static primary stage sample separation device (10).

[0199] It should be noted that the term comprising does not exclude other elements or features and the a or an does not exclude a plurality. Also elements described in association with different embodiments may be combined. It should also be noted that reference signs in the claims shall not be construed as limiting the scope of the claims.