JPH079067Y2 - Micro flow cell measuring device - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Industrial field of application) The present invention relates to a micro flow cell measuring device such as a spectrofluorophotometer used as a detector of liquid chromatography, etc., and particularly to excitation using a horizontally arranged flow cell. The present invention relates to a micro-flow cell measuring device capable of high-sensitivity measurement with little stagnation of liquid and contamination caused by horizontal irradiation of light.

(Prior Art) A spectrofluorometer has been devised in various ways because its main purpose is high-sensitivity measurement. In other words, conventionally, the method of irradiating the sample vertically with the excitation light and taking out the fluorescence horizontally has been the mainstream, but recently, the method of irradiating the excitation light horizontally has also been increasing. The present applicant has previously proposed a microflow cell mounting device suitable for use in this type of spectrofluorophotometer (Japanese Utility Model Publication No. 59-12594).

(Problems to be solved by the device) However, when a microflow cell of this type is used in a spectrofluorometer as a detector for liquid chromatography, the volume of the cell must be reduced and the liquid flowing in the vertical direction must be reduced. On the other hand, since the excitation light enters horizontally,
As a result, the actual cell capacity irradiated with light is reduced, resulting in a problem in sensitivity. Therefore, in order to improve efficiency, it is preferable that the flow cell itself is also arranged horizontally, and for example, a cell as shown in FIG. 1 is generally considered. In the flow cell 21 of FIG. 1, 22 is an inlet hole, 23 is a flow passage, and 24 is an outlet hole. Liquid enters the cell from the lower inlet hole 22 as shown by the arrow, passes through the flow passage, and exits from the outlet hole 24 to the cell. Go out of.

Although such a configuration is the simplest, the liquid flow is poor due to the horizontal arrangement, and in particular, the liquid easily stagnates in the corners shown in the figure, causing contamination, and high-sensitivity measurement is possible. Disturbed.

Therefore, an object of the present invention is to provide a microflow cell measuring device capable of high-sensitivity measurement with little liquid stagnation and accompanying contamination even when horizontally irradiating excitation light using a horizontally arranged flow cell. Especially.

Configuration of the Invention (Means for Solving Problems) In order to achieve the above-mentioned object, the microflow cell measuring device according to the present invention is applied to a spectrofluorometer for the purpose of highly sensitive measurement by irradiating exciting light horizontally. In the horizontal arrangement type micro flow cell measuring device, the micro flow cell is constituted by superposing and welding an upper plate having an outlet hole, an intermediate plate having a flow passage, and a lower plate having an inlet hole in an integrated manner. It is characterized in that a part of each of them is communicated with each end of the flow passage so that the liquid can flow through the communication portion.

As a result, stagnation of the liquid in the flow passage can be avoided, and therefore contamination can be prevented. Since the liquid flow pipe generally has a circular cross section, it is preferable that each of the inlet / outlet holes is circular and each semicircle is communicated with each end of the flow passage.

Further, it is preferable that the upper and lower plates are made of black quartz plates in order to reduce the scattered light so as to weaken the influence thereof and enable higher sensitivity measurement.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to FIG.

First, the structure of the micro flow cell 1 used in the present invention will be described with reference to sectional views and exploded perspective views 2a and 2b.
The micro flow cell 1 comprises three quartz plate members, that is, an upper plate 1-1 having an outlet hole 11 in one side portion (left side in the figure), an intermediate plate 1-2 having a vertically long flow passage 12 in the central portion, and the other side. A lower plate 1-3 having an inlet hole 13 in a portion (right side in the drawing). The micro-flow cell 1 is constructed by laminating these three plates and integrally welding them. Here, the inlet / outlet holes 11 and 13 are formed so as to be partially displaced from the flow passage 12. That is, as is clear from FIG. 2a, each of the holes 11 and 13 does not have the entire opening area thereof in communication with the flow passage 12, but a part of each of them is in communication with each end of the flow passage. In the illustrated example, the right half of the outlet hole 11 communicates with the left end of the flow passage 12, and the left half of the inlet hole 13 communicates with the right end of the flow passage 12, and the liquid flows as shown by the arrow through these communicating portions. To do so.

In the micro flow cell 1 configured as above, the inlet / outlet hole
By arranging only a part of the inlet / outlet holes along the entire length of the flow passage cross-section at both ends of the flow passage of the liquid in the communication portion between the cross-sections 11 and 13 and the flow passage 12, the liquid has a full flow cross-section width. Since they flow through each other, the flow passage cannot have the corners as before, and the liquid flows at the left and right ends of the flow passage 12 without stagnation. Since the liquid flow pipe is generally circular in cross section, it is preferable that the inlet / outlet holes 11 and 13 are also circular and half of each is communicated with each end of the flow passage 12 so that the liquid flows therethrough. .

Next, a measuring device incorporating the above micro flow cell will be described with reference to FIGS. As shown in FIG. 3b, the micro flow cell 1 has upper and lower cell holders 5, 6
The liquid is held horizontally through the Teflon packing 2, respectively, and the liquid enters from the right side of the lower cell holder 6 in the figure as indicated by the arrow, flows through the micro flow cell 1 and flows to the left side of the upper cell holder 5 in the figure. To do. The liquid flowing through the microflow cell 1 is irradiated with the excitation light E as shown in FIG.

The mounting state between the upper and lower cell holders 5 and 6 of the microflow cell 1 is shown in detail in FIG. 4, in which 4 is a mask and 7 is its tightening screw. Although not shown in the figure, a mask similar to the mask 4 is attached to the excitation side. The upper holder 5 can be slid up and down with respect to the lower holder 6 with a tightening screw 8. For a specific configuration in this respect, see the above-mentioned Jitsuko Sho 59-12594.
See No.

Further, when the microflow cell of the present invention is used in liquid chromatography, the cell capacity is small and the fluorescence intensity is limited, and it is easily affected by stray light. Therefore, if the upper and lower quartz plates are made of black quartz, scattered light will be generated. It is preferable because the amount can be reduced and higher sensitivity can be measured.

(Effects of the Invention) As described above, according to the present invention, even when the exciting light is horizontally irradiated by using the horizontally arranged flow cell, the stagnation of the liquid and the accompanying contamination can be effectively reduced by the simple improvement. In addition, a microflow cell measuring device that enables highly sensitive measurement can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the problems when the microflow cell is horizontally arranged, FIGS. 2a and 2b are a sectional view and an exploded perspective view of the microflow cell according to the present invention, and 3a and 3b show the microflow cell respectively. A plan view of the built-in measuring device and a sectional view taken along the line AA ', and FIG. 4 are detailed views showing a mounted state of the microflow cell. 1 ... Micro flow cell, 1-1 ... Upper plate, 1-2 ... Middle plate,
1-3 ... Lower plate, 11 ... Exit hole, 12 ... Flow passage, 13 ... Entrance hole.

Claims (2)

[Scope of utility model registration request] 1. In a horizontally arranged microflow cell measuring apparatus for a spectrofluorometer for the purpose of high-sensitivity measurement by irradiating excitation light horizontally, a microflow cell is provided with an upper plate having an exit hole and a flow passage. The intermediate plate and the lower plate having the inlet hole are integrally welded to each other, and the inlet and outlet holes are substantially circular, and the liquid flows through only the semicircular portion of each end of the flow passage. Micro flow cell measuring device characterized by being able to communicate with. 2. The microflow cell measuring device according to claim 1, wherein the upper and lower plates provided with the liquid inlet / outlet holes are black quartz plates.