Refractive index detector and liquid chromatograph

Patent metadata

Field	Value
Publication number	US-2016274074-A1
Application number	US-201615074000-A
Country	US
Kind code	A1
Filing date	Mar 18, 2016
Priority date	Mar 19, 2015
Publication date	Sep 22, 2016
Grant date	—

Abstract

An embodiment of a refractive index detector includes a sample cell, a reference cell, a measurement section, a liquid inlet port, liquid outlet sections, and a switching mechanism. The inlet port leads to a sample cell inlet. A first outlet port and a second outlet port are for discharging a liquid. The switching mechanism includes a reference liquid supply mode for forming a channel for connecting a reference cell outlet to one of the first outlet port and the second outlet port while connecting a sample cell outlet to a reference cell inlet, and an analysis mode for forming a channel for connecting the sample cell outlet to one of the first outlet port and the second outlet port while sealing the reference cell outlet.

First claim

1 . A refractive index detector comprising:
a sample cell, made of a light transmitting container, including a sample cell inlet through which a liquid flows in, and a sample cell outlet through which a liquid flows out; a reference cell, made of a light transmitting container, including a reference cell inlet through which a liquid flows in, and a reference cell outlet through which a liquid flows out, the reference cell being arranged adjacent to the sample cell across a light transmitting partition wall; a measurement section including a light source for emitting light in such a way that the light passes through both of the sample cell and the reference cell from a side of one of the cells, and a photodetector for detecting displacement of the light which has passed through the sample cell and the reference cell; a liquid inlet port that leads to the sample cell inlet; a first outlet port for discharging a liquid; a second outlet port for discharging a liquid, provided separately from the first outlet port; and a switching mechanism including a reference liquid supply mode for forming a channel for connecting the reference cell outlet to one of the first outlet port and the second outlet port while connecting the sample cell outlet to the reference cell inlet, and an analysis mode for forming a channel for connecting the sample cell outlet to one of the first outlet port and the second outlet port while sealing the reference cell outlet.

2 . The refractive index detector according to claim 1 , wherein the switching mechanism is configured by one rotary switching valve including ports to which the sample cell outlet, the reference cell inlet, the reference cell outlet, the first outlet port, and the second outlet port are connected, and a rotor for switching a connection between ports by rotating, the rotor being provided with a groove for connecting the ports.

3 . The refractive index detector according to claim 2 , wherein the switching valve includes one center port and a plurality of circumferential ports arranged on a circumference having the center port as a center, where the rotor includes two grooves provided in a circumferential direction so as to connect adjacent ports of the circumferential ports, and one groove provided in a radial direction so as to connect the center port and one of the circumferential ports.

4 . The refractive index detector according to claim 3 , wherein, at the switching valve, the sample cell outlet, the reference cell inlet, the reference cell outlet, and the first outlet port are connected to the circumferential ports, the second outlet port is connected to the center port, the reference cell inlet and the first outlet port are connected to ports adjacent to the port to which the sample cell outlet is connected, and the port to which the reference cell outlet is connected and the port to which the first outlet port is connected are adjacent to each other.

5 . The refractive index detector according to claim 3 ,
wherein the switching valve includes, as the circumferential ports, one port to which the reference cell inlet is connected, one port to which the reference cell outlet is connected, two ports to which the first outlet port is connected, and one port to which the second outlet port is connected, and also includes, as the center port, a port to which the sample cell outlet is connected, and wherein, of the circumferential ports, the port to which the reference cell inlet is connected and the port to which the second outlet port is connected are adjacent to one of the ports to which the first outlet port is connected, and the port to which the second outlet port is connected and an other of the ports to which the first outlet port is connected are adjacent to the port to which the reference cell outlet is connected.

6 . The refractive index detector according to claim 1 ,
wherein a recycle channel for returning a liquid to a liquid supply section is to be connected to the second outlet port, and wherein the switching mechanism includes, as the reference liquid supply mode, a reference liquid normal supply mode for connecting the reference cell outlet to the first outlet port while connecting the sample cell outlet to the reference cell inlet, and a reference liquid recycled supply mode for connecting the reference cell outlet to the second outlet port while connecting the sample cell outlet to the reference cell inlet, and includes, as the analysis mode, a normal analysis mode for connecting the sample cell outlet to the first outlet port while sealing the reference cell outlet, and a recycle analysis mode for connecting the sample cell outlet to the second outlet port while sealing the reference cell outlet.

7 . The refractive index detector according to claim 6 , further comprising a control section for controlling an operation of the switching mechanism, the control section including a recycle analysis operation section for placing, based on a detection signal of the photodetector of the measurement section, the switching mechanism in the normal analysis mode when a sample is detected during analysis of the sample, and in the recycle analysis mode when a sample is not detected.

8 . A liquid chromatograph comprising:
a delivery pump for suction a solvent from a solvent container storing the solvent, and delivering the solvent; an analysis channel for delivering, as a mobile phase, the solvent taken in from the solvent container by the delivery pump; a sample introduction section provided on the analysis channel, on a downstream side of the delivery pump, the sample injection section being for introducing a sample into the analysis channel; an analytical column provided on the analysis channel, on a downstream side of the sample introduction section, the analytical column being for separating the sample introduced into the analysis channel by the sample introduction section into sample components; a refractive index detector according to claim 1 , provided on the analysis channel, on a downstream side of the analytical column, the refractive index detector including a liquid inlet port that is connected to an outlet of the analytical column, and a first outlet port and a second outlet port through which a liquid flows out, the refractive index detector being for detecting a sample component separated by the analytical column; and a recycle channel connecting the second outlet port of the refractive index detector and the solvent container, the recycle channel being for returning a liquid flowing out of the second outlet port to the solvent container.

9 . A liquid chromatograph comprising:
a delivery pump for suction a solvent from a solvent container storing the solvent, and delivering the solvent; an analysis channel for delivering, as a mobile phase, the solvent taken in from the solvent container by the delivery pump; a sample introduction section provided on the analysis channel, on a downstream side of the delivery pump, the sample injection section being for introducing a sample into the analysis channel; an analytical column provided on the analysis channel, on a downstream side of the sample introduction section, the analytical column being for separating the sample introduced into the analysis channel by the sample introduction section into sample components; a refractive index detector according to claim 2 , provided on the analysis channel, on a downstream side of the analytical column, the refractive index detector including a liquid inlet port that is connected to an outlet of the analytical column, and a first outlet port and a second outlet port through which a liquid flows out, the refractive index detector being for detecting a sample component separated by the

Assignees

• Shimadzu Corp

Inventors

• Fujiwara Masanori

Classifications

• G01N30/16

  Injection (G01N30/24 takes precedence) · CPC title

• G01N30/74 Primary

  Optical detectors {(measurement of intensity, velocity, spectral content, polarisation, or phase of infrared, visible or ultraviolet light G01J)} · CPC title

• G01N21/41 Primary

  Refractivity; Phase-affecting properties, e.g. optical path length (G01N21/21 takes precedence) · CPC title

• G01N2201/068

  Optics, miscellaneous · CPC title

• G01N21/05

  Flow-through cuvettes (G01N21/09 takes precedence; handling fluid samples G01N1/10) · CPC title