Described are a method and a system for diluting a sample at a location of injection in a liquid chromatography system. The method includes loading a sample into a first fluid channel, separating a flow of a mobile phase into a first flow in the first fluid channel and a second flow in a second fluid channel, and combining the sample that is displaced from the first fluid channel and the mobile phase exiting the second fluid channel at the location of injection into the system flow to thereby generate a diluted sample in the system flow. The dilution ratio of the diluted sample is responsive to the flow rates of the first and second flows. Advantageously, the flow rates can be changed by changing the flow restriction of one of the fluid channels. Thus providing the proper flow restriction enables a user to obtain a desired dilution ratio.

Disclosed are non-contiguous sample fractionating and concatenating device and a dual online multidimensional liquid chromatography system having the same. The non-contiguous sample fractionating and concatenating device according to an embodiment of the present disclosure includes a sample supply module which supplies a sample to be analyzed, and a sample fractionation module connected to the sample supply module, and which is continuously supplied with the sample, sets a plurality of unit sample supply times obtained by equally dividing a total sample supply time during which the sample is supplied from the sample supply module, sets a plurality of unit fractionation intervals obtained by equally dividing each of the plurality of unit sample supply times, and concatenates and stores the sample supplied during corresponding unit fractionation intervals within each unit sample supply time to acquire a plurality of fractions.

A high-pressure switching valve includes a stator and a rotor. The stator includes a plurality of ports where each port is connected at one end to a port connection and having at another end a predetermined port opening cross section at a stator end face of the stator. The rotor includes a rotor end face and at least one or a plurality of grooves. The rotor can be configured to have a rotary position with respect to the stator where two predetermined port opening cross sections connect to one of the grooves in a pressure-tight manner. The rotor and the stator can be pressed together in a sealing manner at the rotor end face and the stator end face in regions away from the port opening cross sections and the at least one or a plurality of grooves. The rotor and the stator each include a hard material. The rotor can be configured to wobble or tilt with respect to a rotational axis of the rotor.

An injection valve switches between a first state in which a sample loop is connected to a separation flow path through which a mobile phase from a liquid sender flows and a second state in which the sample loop is disconnected from the separation flow path. A pump speed determiner, in a case where a sample intake operation by a syringe pump is started immediately after the injection valve is switched from the second state to the first state, and a filling operation of filling the sample loop with the sample by the syringe pump is started after the intake operation is completed, determines an intake operation speed of the syringe pump that is required in order for the filling operation to complete immediately before the injection valve is switched from the second state to the first state next time using a set injection interval time. The syringe pump operates at the intake operation speed determined by the pump speed determiner while performing the intake operation. The sample is injected by the injector at intervals of the set injection interval time.

A sample injection method for liquid chromatography is performed with an injection valve having a waste port, two sample loop ports, and two high-pressure ports. One high-pressure port can be connected to a pump and the other high-pressure port can be connected to a chromatography column. A sample loop is connected to one of the sample loop ports on one end and to a pump volume of a sample conveying device on the other end. A section of the sample loop can be separated to facilitate receiving a sample fluid in the sample loop. A control unit controls the injection valve and the sample conveying device. The sample injector allows a sample to be loaded into the sample loop and then pressurized to an operating pressure prior to injecting the sample into the chromatography column. The sample loop may also be isolated from the operating pressure for facilitating depressurization of the loop.

A supercritical fluid device includes an analytical channel, a liquid delivery part for delivering a mobile phase constituting a supercritical fluid in the analytical channel, a back pressure regulator for controlling a pressure of the analytical channel so as to cause the mobile phase in the analytical channel to reach a supercritical state, a sample injecting device that includes a sample holder for holding a sample and a switching valve for switching between a state where the sample holder is arranged on the analytical channel and a state where the sample holder is not arranged on the analytical channel, a bypass channel whose one end is connected to a position upstream of the sample injecting device and whose other end is connected to a position downstream of the sample injecting device on the analytical channel, and an analytical column for separating a sample introduced by the sample injecting device into individual components, the analytical column is provided downstream of the position to which the other end of the bypass channel is connected on the analytical channel.

A multi-path selector valve used in liquid chromatography and other analytical methods for directing fluid along alternate paths of a flowstream. The selector valve has a stator and a rotor. The dynamic face of the stator has a plurality of openings arranged along an inner ring, a plurality of openings arranged along an outer ring, and an annular collection groove formed in the dynamic face. The inner ring, outer ring, and annular collection groove are concentric circles. The rotor's dynamic face is configured to mate with the rear face of the stator, and has two fluid flow paths. One fluid flow path has one end at a rotational center of the rotor and another end of the fluid flow path is configured to be aligned with a stator opening along the inner ring. The second fluid flow path has one end that is configured to be aligned with the annular collection groove and another end that is configured to be aligned with a stator opening along the outer ring.

A system and method are disclosed for analyzing samples, which includes a spectrometry system for detecting components of a sample; a gas chromatography column for separating the components of a sample; a first sample unit for receiving a first sample from a sample source; and a second sample unit for receiving a second sample from a sample source. Each sample loop unit allows independent processing of samples in preparation for analysis.

An apparatus for controlling fluid flow, and in particular fluid flow through a microfluidic multi-port control valve assembly of a High Pressure Liquid Chromatography (HPLC) unit includes a localized data repository for storing cumulative wear indications of components of the apparatus. The stored information may travel with the apparatus to enable predictive failure of components of the apparatus.

Described are a method and a system for injecting a sample into a flow of a liquid chromatography system. The method includes combining a flow of a sample and a flow of a mobile phase to create a diluted sample in the system flow. The volumetric flow rate of the sample is controlled to be at a value that yields a desired dilution ratio for the diluted sample. The particular value at which the volumetric flow rate is maintained can be determined from the desired value of the dilution ratio and the volumetric flow rate of the mobile phase. System embodiments include a syringe that can be used to provide a sample solution at a controllable volumetric flow rate for combination with a high pressure mobile phase.