A sample management device which comprises a source flow path in which a fluidic sample can flow, a volume flow adjustment unit configured to adjust a volume flow of the fluidic sample to be branched off from the source flow path at a fluidic coupling point, and a fluidic valve fluidically coupled with the source flow path and with the volume flow adjustment unit, wherein the fluidic valve is switchable into a branch off state in which the fluidic coupling point is established within the source flow path to branch off an adjustable volume of the fluidic sample from the source flow path via the fluidic coupling point while a flow of the fluidic sample in the source flow path continues.

A sample management device which comprises a source flow path in which a fluidic sample can flow, a volume flow adjustment unit configured to adjust a volume flow of the fluidic sample to be branched off from the source flow path at a fluidic coupling point, and a fluidic valve fluidically coupled with the source flow path and with the volume flow adjustment unit, wherein the fluidic valve is switchable into a branch off state in which the fluidic coupling point is established within the source flow path to branch off an adjustable volume of the fluidic sample from the source flow path via the fluidic coupling point while a flow of the fluidic sample in the source flow path continues.

The present disclosure relates to methodologies, systems and apparatus for controlling pressure in a CO.sub.2-based chromatography system. A first CO.sub.2 pump operates in constant flow mode and delivers CO.sub.2 to a chromatography column, and liquid modifier is introduced to the chromatography column according to a gradient. A second CO.sub.2 pump is disposed downstream of the column and operates in constant pressure mode to introduce CO.sub.2 into a flow stream at an output of the column. Liquid modifier is also introduced into the flow stream at the output of the column according to a reverse gradient compared to the gradient entering the chromatography column.

The present disclosure relates to methodologies, systems and apparatus for controlling pressure in a CO.sub.2-based chromatography system. A first CO.sub.2 pump operates in constant flow mode and delivers CO.sub.2 to a chromatography column, and liquid modifier is introduced to the chromatography column according to a gradient. A second CO.sub.2 pump is disposed downstream of the column and operates in constant pressure mode to introduce CO.sub.2 into a flow stream at an output of the column. Liquid modifier is also introduced into the flow stream at the output of the column according to a reverse gradient compared to the gradient entering the chromatography column.

The present invention provides a novel method that is capable of detecting a trifluridine-related substance from a sample containing trifluridine or a salt thereof by high-performance liquid chromatography comprising two steps that are performed under gradient conditions. More specifically, the method is for detecting a trifluridine-related substance, the method comprising the step of subjecting a sample containing trifluridine or a salt thereof to high-performance liquid chromatography using a mobile phase composed of an organic phase and an aqueous phase, wherein the step of high-performance liquid chromatography comprises steps 1 and 2 that satisfy the following requirements: Step 1: the percentage of the organic phase in the entire mobile phase is 1 to 14% by volume; and Step 2: after step 1, elution is performed by applying a gradient of increasing the percentage of the organic phase in the entire mobile phase.

The present invention provides a novel method that is capable of detecting a trifluridine-related substance from a sample containing trifluridine or a salt thereof by high-performance liquid chromatography comprising two steps that are performed under gradient conditions. More specifically, the method is for detecting a trifluridine-related substance, the method comprising the step of subjecting a sample containing trifluridine or a salt thereof to high-performance liquid chromatography using a mobile phase composed of an organic phase and an aqueous phase, wherein the step of high-performance liquid chromatography comprises steps 1 and 2 that satisfy the following requirements: Step 1: the percentage of the organic phase in the entire mobile phase is 1 to 14% by volume; and Step 2: after step 1, elution is performed by applying a gradient of increasing the percentage of the organic phase in the entire mobile phase.

Method for controlling a liquid chromatography system comprising a system pump and a column in fluid communication with the system pump by a fluid flow path, the method comprising the steps: registering the system pressure at a flow path position close to the system pump, controlling the operation of the system pump in response to the registered system pressure, estimating a pre-column pressure based on the registered system pressure, the characteristics of the flow path, and the viscosity and flow-rate of the liquid in the system, and controlling the operation of the system pump in response to the estimated pre-column pressure.

Method for controlling a liquid chromatography system comprising a system pump and a column in fluid communication with the system pump by a fluid flow path, the method comprising the steps: registering the system pressure at a flow path position close to the system pump, controlling the operation of the system pump in response to the registered system pressure, estimating a pre-column pressure based on the registered system pressure, the characteristics of the flow path, and the viscosity and flow-rate of the liquid in the system, and controlling the operation of the system pump in response to the estimated pre-column pressure.

The invention provides a process of controlling the impurities of clindamycin hydrochloride, comprising a step of purifying said clindamycin hydrochloride by two-phase high performance liquid chromatography, wherein the chromatographic conditions are as follows: the detection wavelength is 200-220 nm; the column temperature is 20-40 C.; the flow rate is 0.8-1 ml/min; Mobile phase A: 0.025 mol/L potassium dihydrogen phosphate solution; Mobile phase B: Acetonitrile; and gradient elution is performed. The method of controlling impurities of the invention can solve the problem of the interference by excipients and the problem of the separation of many impurities at the same time. It also provides an effective method for setting quality standard of impurities in such a formulation.

A check valve comprises a valve seat element along a fluid path that is formed of a polymeric material and comprises a hole that extends from an input end of the valve seat element to an output end of the valve seat element. The valve seat element includes an inner taper that transitions the input end to the output end, the valve seat element including a sealing surface along the inner taper. A poppet body is formed of a polymeric material and configured to engage the internal tapered sealing surface of the valve seat element. The poppet body moves between a first position at which the poppet body sealingly engages the tapered sealing surface of the valve seat element and a second position at which the poppet body is separate from the inner taper of the valve seat member.