JPH0215031B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a loop injector for intermittently supplying fixed amounts of sample to a continuously flowing carrier solution for automated analysis, and in particular to a loop injector for intermittently dispensing a fixed amount of sample into a continuously flowing carrier solution for automated analysis. This invention relates to a loop injector that can vary the capacity of a flow path while keeping it constant.

The need for chemical and biochemical analysis is rapidly increasing in relation to food and research pollution issues, pharmaceutical and pharmaceutical industry fields, clinical research, etc.
For this reason, methods for quickly and accurately analyzing a large number of various samples have become extremely important. High-speed automatic analyzers are basically divided into the following two types.

In one, each sample is placed in an individual cell,
A large number of cells are automatically transported on a movable belt or the like, and after a reagent is added at a predetermined time, they are sequentially set in the cell section of a spectroscopic analyzer or the like and measurements are performed. This method eliminates the risk of individual samples mixing with each other and enables high-speed analysis, but has the disadvantage that the automated transport equipment becomes extremely complex.

In other systems, samples are taken into the tube in a continuous manner and the samples are processed as a continuous stream of liquid flowing through the tube. Although this method has the advantage of being able to perform high-speed analysis with relatively simple equipment, it has the disadvantage that interference between samples is likely to occur due to the continuous flow. Therefore,
Various methods have been devised to introduce samples into the carrier in a reliably separated state by inserting air bubbles between the samples or by automatic intermittent injection.

By the way, in conventional automatic intermittent injection devices, it is necessary to replace the sampling loop to change the sample amount, and since the flow resistance differs depending on the sampling loop, the flow resistance of the branch loop for carrier introduction also increases. There was the inconvenience of having to readjust.

The purpose of the present invention is to solve the problems of the conventional method as described above, and to provide a loop injector that can change the capacity of the sampling flow path without the need to replace the sampling loop or readjust the branch loop. It is about providing. That is, the variable capacity loop injector according to the present invention is formed between the switching valves for sample intake and sample injection in a device for intermittently supplying a fixed amount of sample to a continuously flowing carrier solution for automatic analysis. This is characterized in that the capacity of the sampling channel is made variable.

In a preferred embodiment of the present invention, a cylinder and a piston are provided in the middle of the sampling flow path, one of the sampling flow paths is communicated with a hollow part inside the cylinder through the cylinder wall, and the other sampling flow path is connected through the piston wall into the cylinder. By communicating with the hollow part of the sampling channel and changing the insertion position of the piston into the cylinder, the capacity of the sampling channel can be made variable.

Further, in a preferred embodiment of the present invention, the piston is constructed as a hollow cylinder, and is equipped with a scale to enable accurate monitoring of the cylinder capacity, and further provided with a scale for fixing the piston to the cylinder. constituted with means.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing an intermittent sample injection system using a variable capacity loop injector according to the present invention. First, the basic structure will be explained. First, 1 is a sample container, 2 is a sampling channel, and a suction tube 3 extending from the sample container 1 is connected to the sampling channel 2 via a switching valve 4. The sampling channel 2 on the same side can also communicate with a sample and carrier introduction tube 5 via a switching valve 4, and this introduction tube 5 is led to a cell section of a spectrophotometer or the like. The other end of the sampling channel 2 can communicate with a sample discharge tube 7 and a carrier introduction tube 8 via a switching valve 6, and these tubes 7 and 8 are connected to a drain and a carrier container (not shown) via a pump 9, respectively. ) is connected to. Further, a branch channel 10 is provided between the sample/carrier introduction tube 5 and the carrier introduction tube 8, and the flow resistance of this branch channel 10 is selected to be larger than the flow resistance of the sampling channel 2. . Furthermore, according to the present invention, the cylinder 11 and the piston 1 are located in the middle of the sampling flow path 2.
2 is provided. This cylinder 11 and piston 1
The sampling flow paths 2 on both sides of the piston 2 communicate with a hollow portion (shaded portion) inside the cylinder 11 through the wall portion of the cylinder 11 and the wall of the piston 12, respectively. The piston 12 is slidable within the cylinder 11, and by changing the insertion position of the piston 12, the capacity of the cylinder 11, that is, the capacity of the entire sampling channel 2, becomes variable.

The operation of the loop injector configured in this way will be described next. First, between 4a and 4b of the switching valve 4 and between 6a and 6b of the switching valve 6 shown by solid lines.
When the pump 9 is operated by communicating between the cylinders 1 and 2, a sample is sucked in from the container 1, filling the sampling channel 2 including the cylinder 11, and excess sample is drained via the switching valve 6. At this time, the carrier that has entered the introduction tube 8 by the action of the pump 9 passes through the introduction tube 5 to the analysis system via the branch channel 10.
being guided to. Also, the piston 12 is connected to the cylinder 1
The insertion position is determined so that the capacity of the entire sampling channel 2 including the capacity of 1 becomes a desired value.
Next, when the sampling channel 2 is filled,
The switching valves 4 and 6 are indicated by dots between 4a-4c and 6a-
6c, the flow resistance is lower in the sampling channel 2 than in the branch channel 10, so the pump 9
The carrier sucked in enters the sampling flow path 2 via the switching valve 6, and the sample therein is pushed out into the introduction tube 5 via the switching valve 4, and directed to a cell section of a spectrometer or the like. Switching valves 4 and 6
By alternately switching the two samples as shown by solid lines and dotted lines and repeating the above operations, a certain amount of sample is intermittently sent to the introduction tube 5, creating a continuous flow that separates from each other and does not mix. and then guided to a spectrometer, etc. After that, when it is desired to change the amount of sample, the overall capacity of the sample flow path 2 is adjusted by changing the insertion position of the piston 12 and changing the capacity of the cylinder 11. in this case,
Since the position of the piston 12 is only changed, the flow resistance of the sample channel 2 remains the same as before, so there is no need to readjust the flow resistance of the branch channel 10.

Further preferred embodiments of the present invention will be described below. FIG. 2 shows a modification of the above-mentioned piston, and this piston 12' consists of a hollow cylinder. In this way, a larger cylinder capacity can be obtained than when the piston is made flat, and is suitable for injecting a relatively large amount of sample.

FIG. 3 shows an example in which a scale 13 is attached to the cylinder 11. In this way, by setting the insertion position of the piston 12 with reference to the scale 13, it becomes possible to accurately select and monitor the cylinder capacity. Also in this embodiment, means 14, such as screws, are provided for fixing the piston, which is slidable within the cylinder, in a desired position, so as to prevent the piston from moving during sample injection and causing fluctuations in the amount of sample. be.

FIG. 4 shows an embodiment for more precisely adjusting the cylinder capacity; in this example, the piston and cylinder constitute a micro gauge 15. In other words, the frame 16 of the micro gauge 15
A cylinder 11 is formed on both sides of the cylinder 11 , and a spindle sliding inside this cylinder 11 serves as a piston 12 . The method of measurement is the same as in the case of a normal micro gauge, and 14 is a means for fixing the piston (spindle) 12. This embodiment is suitable for accurately determining the capacity of the sampling flow path when the sample amount is small (up to several μ).

Although the configurations of the cylinder and piston portions have been explained for each of the above modified embodiments, the method of operation as a loop injector is the same as in the first embodiment.

As described above, according to the present invention, the amount of sample to be injected can be changed without replacing the sampling loop with a simple configuration in which a cylinder and a piston are provided in the sampling flow path. The advantageous advantage is that the flow resistance of the channel remains constant so that no readjustment of the flow divider loop is necessary.

[Brief explanation of drawings]

1 is a diagram showing an intermittent sample injection system using a loop injector according to the present invention; FIG. 2 is a diagram showing another embodiment of the cylinder and piston portion of the loop injector according to the present invention; FIG. FIG. 4 is a diagram showing still another embodiment. DESCRIPTION OF SYMBOLS 1...Sample container, 2...Sampling channel, 3...Suction tube, 4, 6...Switching valve, 5
... Sample/carrier introduction tube, 7 ... Sample discharge tube, 8 ... Carrier introduction tube, 9 ... Pump, 10 ... Branch flow path, 11 ... Cylinder, 12, 12' ... Piston, 13 ... Scale , 14... Fixing means, 15... Micro gauge, 16... Frame.

Claims (1)

[Scope of Claims] 1. A device for intermittently supplying a fixed amount of sample to a continuously flowing carrier solution for automatic analysis, in which the sampling flow path is formed between switching valves for sample intake and sample injection. A cylinder and a piston are provided in the middle, one sampling channel is communicated with the hollow part in the cylinder through the cylinder wall, the other sampling channel is communicated with the hollow part in the cylinder through the piston wall, and the piston is inserted into the cylinder. A variable capacity loop injector characterized in that the capacity of a sampling channel is made variable by changing its position. 2. The variable capacity loop injector according to claim 1, wherein the piston is formed of a hollow cylinder. 3. The variable capacity loop injector according to claim 1, wherein a scale is provided on the cylinder, and the insertion position of the piston can be detected by the scale, and the cylinder capacity can be monitored. 4. The variable capacity loop gauge according to claim 1, wherein the cylinder is formed between frames of a microgauge, and the piston is a spindle of the microgauge and is slidable inside the cylinder. Ekta. 5. The variable capacity loop injector according to claim 1, further comprising means for fixing the piston to the cylinder.