Abstract: The present invention is directed to reduce the dead volume in a flow path with trap functions. A flow path switching valve 1 is provided, which includes a rotor, i.e., rotor 3, and a housing top 9 having four ports 7a-7d connected to external flow paths, wherein two ports used for a mobile phase for analyzing are an inlet port 7a and an outlet port 7b, and the other two ports used for a mobile phase for condensing are an inlet port 7c and an outlet port 7d. In the rotor 3, two circular arc-shaped rotor trenches 11a, 11b for communicating two ports are formed at positions corresponding to the ports 7a-7d. The rotor trench 11b is filled with an adsorbent.

Abstract: A liquid chromatograph having a flow passage switching mechanism for switching among a normal analysis flow passage formed by connecting a mobile-phase-sending-unit, a second mixer having a large capacity, a sample injection portion, an analysis column and a detector in this order, a concentration flow passage formed by connecting a concentration liquid sending unit for sending a liquid for transferring a sample to be concentrated, the second mixer, the sample injection portion and a trapping column in this order, and a concentration analysis flow passage formed by connecting the mobile-phase-sending-unit, a first mixer having a smaller capacity than the second mixer, the trapping column, the analysis column and the detector in this order so that any one of the three flow passages is selectively formed, The mobile-phase-sending-unit is set so that the flow rate of a mobile phase becomes smaller when the concentration analysis flow passage is selected than when the normal analysis flow passage is selected.

Abstract: A liquid chromatograph having a flow passage switching mechanism for switching among a normal analysis flow passage formed by connecting a mobile-phase-sending-unit, a second mixer having a large capacity, a sample injection portion, an analysis column and a detector in this order, a concentration flow passage formed by connecting a concentration liquid sending unit for sending a liquid for transferring a sample to be concentrated, the second mixer, the sample injection portion and a trapping column in this order, and a concentration analysis flow passage formed by connecting the mobile-phase-sending-unit, a first mixer having a smaller capacity than the second mixer, the trapping column, the analysis column and the detector in this order so that any one of the three flow passages is selectively formed, The mobile-phase-sending-unit is set so that the flow rate of a mobile phase becomes smaller when the concentration analysis flow passage is selected than when the normal analysis flow passage is selected.

Abstract: An elution test method measures the elution process of a specific component in a process where a preparation containing at least the specific component subject to a change with time in chemical properties after elution and an impurity component not subject to a change with time in chemical properties after elution is eluted into a test liquid. The method obtains a ratio of absorbance k of the impurity component and a ratio of absorbance k? of the specific component at two isosbestic point wavelengths ?1, ?2 in a spectrum including the specific component and its decomposed matter, and calculates at least one of the absorbances A1(t), A2(t) of said specific component by using k×C2(t)?C1(t)=k×A2(t)?A1(t) and A1(t)/A2(t)=k? from the absorbance C1(t), C2(t) at said two isosbestic point wavelengths ?1, ?2 measured at the plural time points t in the elution process of said preparation, and converts the result to an elution concentration.

Abstract: A liquid chromatograph has switching valves as a flow passage switching mechanism and an automatic sampler as an injection section. The liquid chromatograph can switch, by switching the switching valves between a concentration flow passage for concentrating the sample injected by the automatic sample via a flow passage which connects the automatic sampler to the trapping column; a concentration analysis flow passage for separating and analyzing the concentrated sample on a per-composition basis which connects the trapping column to the analysis column; and a direct analysis flow passage by separating the sample on a per-composition basis which connects the automatic sampler to the analysis column.

Abstract: [PROBLEMS] To prevent a specimen from being diffused by the improper capacity of tubing. [MEANS FOR SOLVING PROBLEMS] This specimen pretreating device comprises a micro scale or nano scale high-performance liquid chromatograph having a capillary column (2), a probe (1) integrally formed at the tip of the capillary column (2), and an additive feeding flow passage (16). The probe (1) is formed in a multi-tube structure in which a plurality of tubes are disposed on a same axis. The innermost tube is located at the tip of the capillary column (2), and one of the outer tubes is used as an additive supply tube converging an additive solution to an eluent solvent eluted from the capillary column (2) to form liquid drips including the eluent solvent and an additive and the liquid drips are dripped from the tip of the prove (1). The specimen is not diffused since a detector is not present it the flow passage.

Abstract: The present invention provides an apparatus for analyzing easily not only the overall taste of a sample but also what kind of components, synergetic effects and diminishing effects contribute to the taste. A sample to be analyzed is injected into a mobile phase by a liquid sending pump, and the sample is sent to a taste detector by way of a blending means and valves. Then, detection signals are obtained by taste sensors on the taste detector. The sample sent through the taste detector is introduced into a column by way of a 6-port-2-position valve, temporally separated into components and eluted from the column. After each component is detected by a UV detector, the eluted liquid is sent to the taste detector once more, and detection signals which reflect the tastes of each sample component. When analyzing how the taste changes by an additive, send the additive to the blending means and blend it with the sample.

Abstract: A flow path switching valve is provided, in which an impact due to the pressure change when a flow path is switched is prevented from being generated. (A) A rotor slot 1c allows an analysis infusion pump 11 to be connected to an analytical column 13, so as to form a flow path (condensing procedure). (B) The rotor of the flow path switching valve 1 is rotated clockwise for 30 degrees, the rotor slot 1c allows the analysis infusion pump 11, the analytical column 13, and a trap column 5 be connected. After the pressure in the trap column 5 is raised to the same pressure level as that of the analytical column 13, the pressure is stabilized, and the pressure difference between the two columns 5 and 13 is counteracted (high-pressure procedure).

Abstract: The present invention is directed to reduce the dead volume in a flow path with trap functions. A flow path switching valve 1 is provided, which includes a rotor, i.e., rotor 3, and a housing top 9 having four ports 7a-7d connected to external flow paths, wherein two ports used for a mobile phase for analyzing are an inlet port 7a and an outlet port 7b, and the other two ports used for a mobile phase for condensing are an inlet port 7c and an outlet port 7d. In the rotor 3, two circular arc-shaped rotor trenches 11a, 11b for communicating two ports are formed at positions corresponding to the ports 7a-7d. The rotor trench 11b is filled with an adsorbent.

Abstract: A two-dimensional liquid chromatograph includes a first-dimension separation channel for guiding a sample injected from a sample injection part to a first-dimension analysis column using a first-dimension analysis mobile phase for separation; two trap columns; an analysis channel for guiding components retained in the trap columns to a second-dimension analysis column using a second-dimension analysis mobile phase for analysis; and a channel switching mechanism. The switching mechanism connects the first-dimension separation channel to one of the trap columns and connecting the analysis channel to the other of the trap columns, and also switches connections between the trap columns and the channels.

Abstract: The probe has a triple tube structure, in which an eluate from a liquid chromatograph flows through an innermost flow passage, a matrix solution flows through a flow passage outside the innermost flow passage, and the air or acetone flows through an outermost flow passage. Before analysis, acetone is flowed to rinse the matrix compound deposited in the previous analysis and clean the tip portion of the probe, and then the air is flowed to evaporate the rinsing solution.

Abstract: A tip portion of a probe has a triple tube structure in which a fused silica capillary on the innermost side, a capillary made of FEP outside the fused silica capillary, and a stainless pipe on the outermost side are disposed coaxially. An eluate from a liquid chromatograph flows through the innermost flow passage, a matrix solution flows through the flow passage between the fused silica capillary and the FEP capillary, and a rinsing solution or air flows through the flow passage between the FEP capillary and the pipe.

Abstract: A distal end portion of a probe has a multi-pipe structure, in which an effluent solution from a high speed liquid chromatography passes through an innermost flow passage, a matrix solution through an outer flow passage, and the air through an outermost flow passage. A distal end of the outermost pipe extends 1.2 mm longer than the distal end of the inner duplex tube to form a liquid reservoir. When dropping a liquid droplet from the distal end of the probe, the air is blown out to expel the liquid gathered in the liquid reservoir to be dropped.

Abstract: In a preferred embodiment, a sample container storage part for storing a number of sample containers S, a nozzle for dropping a sample component separated and supplied by an LC and an additive liquid such as digestive fluid supplied from another liquid supplying part to the sample container S, a carrying mechanism for carrying and positioning the sample container at an arbitrary position under the nozzle, and a second nozzle, serving as a suction/injection mechanism, for sucking in the fractionated/collected sample component and injecting the sample component to another LC. The carrying mechanism provides a rotation mechanism. The carrying mechanism rotates over 180 degrees and carries the sample container S completed with fractionating/collecting to the position of the second nozzle, and the sample is sucked in by the second nozzle and injected to the LC of next stage.

Abstract: A proximity sensor for measuring a distance between a probe and a sample plate is provided a sideway of the probe. The sample plate is mounted on a stage and moved vertically and horizontally. The stage is connected to a control unit for controlling the movement of the stage. The control unit makes a feedback control for the stage so that the measured value of the proximity sensor may be set to a preset value. When dropping a liquid droplet from the probe, the sample plate is moved upwards to shorten the distance between the probe and the sample plate and contact the liquid droplet with the sample plate, whereby the solution is fractionated.

Abstract: An elution test method measures the elution process of a specific component in a process where a preparation containing at least the specific component subject to a change with time in chemical properties after elution and an impurity component not subject to a change with time in chemical properties after elution is eluted into a test liquid. The method obtains a ratio of absorbance k of the impurity component and a ratio of absorbance k? of the specific component at two isosbestic point wavelengths ?1, ?2 in a spectrum including the specific component and its decomposed matter, and calculates at least one of the absorbances A1(t), A2(t) of said specific component by using k×C2(t)?C1(t)=k×A2(t)?A1(t) and A1(t)/A2(t)=k? from the absorbance C1(t), C2(t) at said two isosbestic point wavelengths ?1, ?2 measured at the plural time points t in the elution process of said preparation, and converts the result to an elution concentration.

Abstract: In a preferred embodiment, a sample container storage part for storing a number of sample containers S, a nozzle for dropping a sample component separated and supplied by an LC and an additive liquid such as digestive fluid supplied from another liquid supplying part to the sample container S, a carrying mechanism for carrying and positioning the sample container at an arbitrary position under the nozzle, and a second nozzle, serving as a suction/injection mechanism, for sucking in the fractionated/collected sample component and injecting the sample component to another LC. The carrying mechanism provides a rotation mechanism. The carrying mechanism rotates over 180 degrees and carries the sample container S completed with fractionating/collecting to the position of the second nozzle, and the sample is sucked in by the second nozzle and injected to the LC of next stage.

Abstract: In a trap flow path, two diluents are supplied by solvent pumps that can respectively determine the flow rates independently. One of the diluents is allowed to pass through a fraction loop so as to direct a fractioned component(s) held in the fraction loop to a trap column together with a mobile phase. The other diluent is allowed to join with a flow path that has passed through the fraction loop on the downstream side of the fraction loop, and flows to the trap column while diluting the mobile phase from the flow path. In the trap column, the sample component(s) is condensed while being trapped therein.

Abstract: A two-dimensional liquid chromatograph includes a first-dimension separation channel for guiding a sample injected from a sample injection part to a first-dimension analysis column using a first-dimension analysis mobile phase for separation; two trap columns; an analysis channel for guiding components retained in the trap columns to a second-dimension analysis column using a second-dimension analysis mobile phase for analysis; and a channel switching mechanism. The switching mechanism connects the first-dimension separation channel to one of the trap columns and connecting the analysis channel to the other of the trap columns, and also switches connections between the trap columns and the channels.

Abstract: A liquid chromatograph has switching valves as a flow passage switching mechanism and an automatic sampler as an injection section. The liquid chromatograph can switch, by switching the switching valves between a concentration flow passage for concentrating the sample injected by the automatic sample via a flow passage which connects the automatic sampler to the trapping column; a concentration analysis flow passage for separating and analyzing the concentrated sample on a per-composition basis which connects the trapping column to the analysis column; and a direct analysis flow passage by separating the sample on a per-composition basis which connects the automatic sampler to the analysis column.