JPH0527666U - Automatic sample introduction device - Google Patents

Abstract

(57) [Summary] [Structure] The sample introduction device consists of a plurality of sample bottles installed in a rack and freely moving needles, a switching valve, a measuring syringe, an injection valve, an injection port and a washing port. By providing a switching valve capable of switching to a plurality of flow paths between the needle and the measuring syringe, a plurality of types of washing liquids / reagents can be arbitrarily and selectively switched for use. [Effect] Complete cleaning can be performed by selectively switching between several kinds of cleaning liquids and using them appropriately, and it is possible to use with samples that are difficult to clean and reagents containing salts and acids, and to prevent cross contamination. In addition, the operation of diluting / adding liquid can be achieved with the minimum flow path configuration, and the measuring accuracy of the diluting liquid / adding liquid is improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sample introduction device having a mechanism that enables the use of a plurality of types of cleaning liquids and reagents in an automatic sample introduction device for liquid chromatography.

[0002]

[Prior Art]

 1 and 2 show a conventional flow path system.

The sample introduction device injects a liquid sample into a plurality of sample bottles, and inhales the sample with a measuring syringe installed on a rack or a turntable and connected to a needle to perform sampling. It is a device that repeats these operations in sequence and performs them continuously. As a method of sample injection, the needle is connected to a measuring syringe and one type of reagent (washing liquid) via a three-way switching valve. The space between the needle and the measuring syringe is filled with the reagent in advance, and in this state, the sample is moved to the position of the predetermined sample bottle, and the set amount of the liquid sample is actuated by the measuring syringe to be sucked into the needle. Next, the needle moves to the injection port connected to the injection valve, and the metering syringe is discharged into the sample loop connected to the injection valve to deliver the liquid sample. Next, the injection valve is switched to the flow path connected to the column side to introduce the sample. After that, the reagent (washing liquid) is sucked and discharged to wash the inner and outer walls of the needle to prepare for the next analysis. As described above, only one type of reagent (washing liquid) flow path serves to transport and wash the liquid sample. Also, when diluting or adding to a liquid sample using different reagents, it is performed by installing two or more switching valves and a metering cylinder. When the cleaning solution was exchanged for each analysis or when switching to a different cleaning solution at the end of the analysis, the cleaning solution was replaced manually.

[0004]

[Problems to be solved by the device]

 The above-mentioned sample introduction device of the prior art is a flow path system for one type of cleaning liquid and only one type of cleaning liquid (reagent). As described above, one type of cleaning solution (reagent) serves both to transport the liquid sample and to clean the flow path system in contact with the needle sample. In a general-purpose device, various reagents are used for measurement under various analytical conditions. In general, the same eluent as the eluent is used as the washing solution to prevent the fluctuation of the baseline due to the shock of the solvent, so reagents containing salts and acids are often used. Since these reagents are highly corrosive, they easily corrode the wetted parts. For this reason, it is necessary to thoroughly wash with water etc. after each use. In particular, in the case of a reagent containing a salt or an acid, deposits are likely to occur during drying, and the sliding surface is likely to be damaged. To prevent these, cleaning with water after each analysis is essential. When changing the washing solution (reagent) in each analysis in the conventional equipment or at the end of the analysis, the washing solution (reagent) itself must be replaced in consideration of the timing of the analysis. There was a problem in that bubbles could be mixed into the flow channel due to replacement, and it would take time due to stability after replacement and continuous automatic analysis could not be performed. In addition, when diluting / adding to a liquid sample, two or more switching valves and measuring syringes are used, but the volume of flow paths such as pipes and joints increases, leading to a decrease in the measuring accuracy of the diluting liquid / addition liquid. It was An object of the present invention is to provide a flow channel system in which several kinds of reagents can be connected by providing a switching valve for a plurality of flow channels in the flow channel between the washing liquid and the needle, and the reagents can be arbitrarily selected.

[0005]

[Means for Solving the Problems]

 The purpose above is to add a valve that allows multiple channels to be arbitrarily switched to the channel that connects the needle and the washing solution (reagent), enabling the connection of several types of washing solution (reagent), and making several types of washing solution (reagent) optional. It is possible to select. A valve switching operation command can be used to switch between the carrier liquid used when sampling a liquid sample and the cleaning liquid that performs cleaning after sampling, or the dilution / addition liquid operation that switches several different reagents. It is a thing.

[0006]

[Action]

 A valve that can switch multiple channels is installed in the channel between the washing liquid (reagent) and the needle. A measuring syringe is connected to one of the switching valves, and one of the reagents is connected to a carrier liquid used for carrying a liquid sample. The carrier liquid is generally the same as the eluent to prevent solvent shock. Several reagents to be used as washing liquid are connected to the second and subsequent reagents. When measuring a liquid sample, switch the flow path of the switching valve to the delivery side and suck into the measuring syringe. Next, switch the switching valve to the needle side and discharge. At this time, place the needle on the drain side. Repeat this operation several times to fill the channel for sucking the sample. In this state, the needle is moved to a predetermined sample bottle position and a predetermined amount is sucked. Next, discharge into the sample loop connected to the injection valve and sample. Next, in preparation for the next sampling, the needle and injection port are operated to wash the inner and outer walls of the needle and the flow path through which the liquid sample has passed with a cleaning solution. Several kinds of cleaning liquid can be used properly in these series of operations. In addition, liquid pretreatment operations such as dilution and addition to a liquid sample using different types of reagents can be easily performed by arbitrary and selective switching operation of a switching valve that can switch to multiple channels. .

[0007]

【Example】

FIG. 3 shows an embodiment of the present invention. The arbitrarily moving needle 9 is connected to the measuring syringe 13 and the washing liquid (R ₁ ) 14 via a multi-channel switching valve 18. Plural kinds of reagents Rn can be connected to the plural flow path switching valve 18. FIG. 4 shows a structural diagram of the multi-channel switching valve 18. A rotor seal 21 that moves to an arbitrary position is in pressure contact with the stator 20. The rotor seal 21 is provided with a switching groove 19 that communicates with the flow path hole 17, and the cleaning liquid (reagent) is determined by the position of the switching groove 19 that is arbitrarily rotated. One of the communicating switching grooves 19 is always connected to the measuring syringe 13, and any cleaning liquid (reagent) can be selected by rotating the position of the switching groove 19. The tube 11 connecting the needle 9 and the plural flow path switching valve 18 is filled with the cleaning liquid R ₁ (reagent) 14 by the measuring syringe 13. The needle 9 moves to a predetermined position of the sample bottle 8 installed in the rack space and descends into the sample bottle 8 by the arm up / down mechanism to suck a set amount. Next, the arm is moved and inserted into the injection port 6 connected to the sample loop 5 of the injection valve 4. The liquid syringe 24 is sent into the sample loop 5 by discharging the measuring syringe 13. Next, the flow path of the injection valve 4 is switched to the analysis flow path to introduce the liquid sample 24 into the column 3. After the introduction is completed, the multi-channel switching valve 18 for cleaning the channels of the sampling line needle 9, the injection port 6, and the injection valve 4 is switched to the position of the cleaning solution R ₂ 15 The cleaning solution is sucked and discharged by the measuring syringe 13. It switches to the flow path of the cleaning liquid R ₂ 15. The cleaning liquid R ₂ 15 cleans the flow path of the needle 9, the injection port 6, and the injection valve 4 of the sampling line. Several kinds of cleaning liquids can be connected and can be used arbitrarily and selected. This makes it possible to separately use the liquid sample transporting solution and the cleaning solution. By separating the carrier liquid and the cleaning liquid, the same carrier liquid as the eluent can be used, and the fluctuation of the baseline due to the difference in the absorbance of the solvent that occurs during sampling can be suppressed. In addition, a solvent containing salt or acid can be used as a carrier liquid because it can be easily switched to the cleaning liquid, and corrosion of the flow path system can be prevented. In addition, a liquid that is difficult to wash (difficult to dissolve) can be washed completely with several types of washing liquid. Moreover, since several kinds of reagents can be used by switching a plurality of channels, it is possible to add a diluent to a liquid sample or an internal standard. An example in which a reagent is connected to the diluent R ₃ 23 and a predetermined amount is added to each sample vial will be described. The sample bottle 8 is installed at a predetermined position on the rack 10. The switching groove 19 of the plural flow path switching valve 18 is switched to the position of the diluent R ₃ 23, and a predetermined amount is sucked by the operation of the measuring syringe 13. Next, the needle driving unit is operated to move the needle 9 to the position of the washing port 7 and discharge a predetermined amount for filling the space between the needle 9 and the plural flow path switching valve 18 with the diluting liquid R ₃ 23. Next, the needle 9 is moved to a predetermined position of the sample bottle 8 and lowered into the sample bottle 8 to discharge a predetermined amount of diluent. Repeat with each sample bottle to add diluent R ₃ 23. After completion, multiple channels cut switch valve 18 is switched groove 19 is switched cleaning liquid R ₁ 14 is connected to the flow path of the cleaning liquid R ₁ 14. The cleaning liquid R ₁ 14 is sucked and discharged by the measuring syringe 13 to clean the space between the needle 9 and the needle-switching valve. After washing, a predetermined amount is sucked from a predetermined sample bottle 8, the needle 9 is moved to the injection port 6 and discharged, and sampling is performed. After sampling, the sampling line of the needle 9, the injection port 6 and the injection valve 4 is washed with the washing liquid R ₂ 15 to prepare for the next sampling. These series of operations can be arbitrarily set and selectively performed. By thus providing the switching valve 18 of a plurality of flow paths, it is possible to easily switch several kinds of cleaning liquids, add a diluting liquid, an internal standard, etc. with a minimum flow path system.

[0008]

[Effect of the device]

 According to the present invention, by providing a valve capable of switching a plurality of flow paths, it is possible to arbitrarily and selectively switch and use the cleaning liquid, which has been fixed to one type in the related art, by an easy operation. This is particularly effective when a reagent containing salt or acid is used as the cleaning liquid. This is because the reagent used as the eluent and the carrier liquid is often the same as the eluent in order to suppress the baseline change due to the difference in the absorbance of the solvent. After use, it is possible to switch to a cleaning liquid (one that has a high cleaning effect such as water) and perform cleaning to prevent corrosion of the wetted parts due to salt or acid and to reduce damage to the sliding part due to precipitates such as crystals. . In addition, in the flow path system of the conventional device, the addition and dilution of reagents, which required two or more switching valves and two or more measuring syringes, could be performed with one measuring syringe. In addition, since the flow path system for dilution / addition can be set to the minimum length and volume, it is possible to improve the measurement accuracy of dilution / addition, and the liquid pretreatment function with the minimum flow path configuration. In addition, it was possible to obtain a sample introduction device that has the above-mentioned features and is capable of significantly reducing costs.

[Brief description of drawings]

FIG. 1 is a diagram showing a flow path system according to an embodiment of the prior art.

FIG. 2 is a diagram showing a flow path system in the case of performing dilution / addition in a liquid pretreatment of a conventional technique.

FIG. 3 is a diagram showing a flow channel system of the automatic sample introduction device of the present embodiment.

FIG. 4 is a structural diagram of a multi-channel switching valve of this embodiment.

[Explanation of symbols]

1 ... Eluent, 2 ... Pump, 3 ... Column, 4 ... Injection valve, 5 ... Sample loop, 6 ... Injection port, 7 ... Wash port, 8 ... Sample bottle, 9 ... Needle, 10 ... Rack,
11 ... Connection tube, 12 ... 3-way switching valve, 13
... dosing syringe, 14 ... cleaning liquid R ₁ (reagent), 15 ... cleaning liquid R ₂ (reagent), 16 ... cleaning liquid R ₃ (reagent), 17 ...
Nagareroana, 18 ... plurality flow path switching valve, 19 ... switching groove 20 ... stator, 21 ... rotor seal, 22 ... compression spring, 23 ... dilutions R _n, 24 ... liquid sample, 25 ... joint, 26 ... Weighing Syringe 2, 27 ... 3-way switching valve 2.

Claims (2)

[Scope of utility model registration request] 1. A liquid sample is placed in a plurality of sample containers and set at a predetermined position, and the sample is sucked by a hollow needle mounted on a mechanism variable in XY directions and discharged by a dispensing function. An automatic sample introduction device having a valve capable of switching to a plurality of flow paths for a washing liquid and a reagent in a sampling system. 2. The automatic sample introduction device according to claim 1, wherein a plurality of types of washing liquids and reagents can be switched by a valve capable of arbitrarily and selectively switching a plurality of flow paths.