JPS5942260B2 - Continuous measurement PH meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous measurement pH meter that can aseptically and continuously measure the pH (hydrogen ion concentration) of blood, etc.

PH (■l) Anisotropy can be roughly divided into electrical measurement methods and colorimetric measurement methods. Among the electrical measurement methods mentioned above, the glass electrode method is particularly used for the measurement of biochemical samples. There is.

Conventional glass electrode type PH meters use a pair of glass electrodes and a reference electrode, and measure the potential difference between them to determine the PH.
However, after calibrating the zero point and sensitivity of the glass electrode using a calibration standard solution, disinfecting it will disrupt the calibration, so it is not recommended to sterilize the glass electrode. Moreover, since the internal liquid is constantly flowing out into the test liquid from the liquid junction provided on the reference electrode to establish electrical connection, continuous measurement cannot be performed under sterile conditions.

The present invention utilizes two glass electrodes having the same characteristics as a microporous membrane that prevents contamination with a test liquid such as an electrolytic solution into which the electrodes are inserted, while allowing electrical conduction between the two liquids. This eliminates the drawbacks of the prior art, and the details will be explained below with reference to the drawings.

The drawings show one embodiment of the present invention, and 1 is a container body. This container body 1 is an electrolytic chamber into which an electrolytic solution 4 is placed, formed by microporous membranes 2 and 3 having numerous micropores with a pore size of 0.22μ or less, that is, a pore size that prevents solution from entering and bacteria from passing through. The electrolyte chamber a is divided into the electrolyte chamber a, the test liquid chamber b, which holds a test liquid 5 such as blood, and the sample chamber c, which holds a sample 6 such as a calibration standard or test liquid 5. A comparison electrode T is inserted into the test liquid chamber b, and a well-known glass electrode 8 is inserted into the sample chamber c.
A calibration glass electrode 9 having the same characteristics and structure as the glass electrode 8 is inserted into the calibrating glass electrode 9 . The above microporous membranes 2 and 3
The electrolyte 4 placed in the electrolyte chamber a, the test liquid 5 placed in the test liquid chamber b, the electrolyte 4 placed in the electrolyte chamber a, and the sample liquid 5 placed in the sample chamber c (calibration) The sample liquid (standard sample 6, test liquid 5, etc.) is prevented from flowing between them while maintaining electrical continuity between the two adjacent liquids. Therefore, the test solution 5 in the test solution chamber b and the electrolyte solution 4 in the electrolyte solution chamber a do not mix, and even if bacteria are present in the electrolyte solution 4, these bacteria are not adjacent to each other. It does not enter into the test liquid 5. Further, the test liquid chamber b is surrounded by the microporous membrane 2 and other wall portions in a sterile state. The test liquid chamber b has a supply pipe 10 that continuously supplies the test liquid 5 into the test liquid chamber b, and a discharge pipe 10 that discharges the test liquid 5 sent into the test liquid chamber b through this pipe 10 to the outside. A branch pipe 12 is attached to the supply pipe 10 to take out an appropriate amount of the test liquid 5 to the sample chamber c by opening and closing an on-off valve when necessary.
is provided. Further, a well-known meter such as a voltmeter is installed between the glass electrodes 8, 9 and the comparison electrode 7 to alternatively measure the potential difference occurring between them. 13 are arranged.
Note that the measuring instrument 13 is provided with the same calibration means for calibrating the zero points and sensitivities of the two glass electrodes 8 and 9, but these are omitted in the drawing. Next, an example of use and operation of the continuous measurement PH meter according to the present invention having the above configuration will be explained. First, the glass electrode 8, test liquid chamber b, etc. are disinfected, and then two types of calibration standard solutions with known pH values are immediately added to the sample chamber C alternately to set the zero point for the calibration glass electrode 9. Perform sensitivity calibration.

Next, the branch pipe 12 is opened and the sample liquid 5 such as blood or body fluid is inserted.
is introduced into a small amount of sample chamber c as sample 6, and its P
Measure H. After this operation is completed, the test liquid 5 is introduced into the test liquid chamber b, and the measuring device 13 is adjusted so as to indicate the same pH value as the sample 6. As a result, the zero point for the glass electrode 8 will be calibrated. After the above operation, the test liquid 5 such as blood or body fluid is caused to flow into the test liquid chamber b, and the pH of the test liquid 5 is continuously measured. In the above, when measuring pH, there is electrical continuity between the electrolytic solution 4 and the test liquid 5 through the microporous membrane 2. The pore diameter of the micropores in the microporous membrane 2 is 0.22μ or less. Therefore, bacteria will not pass through the microporous membrane 2 and contaminate the test liquid 5. Needless to say, if stability is a concern due to long-term measurements, recalibration should be performed in a sterile manner using the same procedure as described above. As explained above, in the continuous measurement pH meter of the present invention, the test solution 5 and the electrolyte solution 4 are formed into numerous micropores with a pore size of about 0.22μ or less that can prevent the solution from entering and the passage of bacteria. are separated by a microporous membrane 2 with holes in it, and bacteria will not be mixed in with the test liquid 5 in the test liquid chamber b kept in a sterile condition, so the pH of blood and body fluids can be maintained in a sterile manner. and can be measured continuously.

In addition, a calibration glass electrode 9 having the same structure and characteristics as the glass electrode 8 is installed in this device under the same conditions as the glass electrode 8, and this calibration glass electrode 9 indirectly determines the sensitivity and zero point of the glass electrode 8. Since the glass electrode 8 can be maintained sterile, the desired purpose can be achieved.

[Brief explanation of the drawing]

The drawing is a sectional view showing the basic structure of the continuous measurement PH meter according to the present invention. 2...Microporous membrane, 3...Microporous membrane, 4
... Electrolyte solution, 5 ... Test liquid, 6 ...
... Sample, 7... Reference electrode, 8...
...Glass electrode, 9...Glass electrode for calibration, 1
3... Measuring instrument, a... Electrolyte chamber, b.
...Test liquid chamber, c...Sample chamber.

Claims (1)

[Claims] 1 One wall is composed of a microporous membrane with numerous micropores with a pore diameter of about 0.22μ or less to prevent solution from entering and bacteria from passing through, and this microporous membrane and other walls are Therefore, there is a test liquid chamber which is surrounded in a sterile state and into which the test liquid is continuously supplied, and a test liquid chamber which is connected to the test liquid chamber via the microporous membrane and has a comparative test liquid inside. an electrolytic solution chamber into which an electrolytic solution is placed; a sample chamber which is connected to the electrolytic solution chamber via a microporous membrane that prevents solution from entering; and into which the test solution is placed as a calibration sample; two glass electrodes with the same characteristics inserted into the liquid chamber and the sample chamber, respectively, and a reference electrode inserted into the electrolyte chamber;
A continuous measurement PH meter comprising a measuring device disposed between the two glass electrodes and the reference electrode to alternatively measure the potential difference occurring between these electrodes.