use and maintenance

1. The electrode must be calibrated with a standard buffer solution with a known pH value before measurement. To improve measurement accuracy, the pH value of the buffer solution should be reliable, and the closer it is to the measured value, the better, generally not exceeding 0.3 pH.

2. The sensitive glass bulb at the front end of the electrode should not come into contact with hard objects, as any damage or scratching will cause the electrode to fail.

3. The pole socket must be kept highly clean and dry. If it is contaminated, it can be wiped clean with medical cotton and blown dry to prevent short circuits at both ends of the output, otherwise it will cause measurement errors or failures.

4. Before measurement, attention should be paid to throwing away the bubbles inside the glass bubble, otherwise it will cause measurement errors. During measurement, the electrode should be stirred in the test solution and placed still to accelerate the response.

5. Before and after measurement, the electrode should be cleaned with deionized water to ensure measurement accuracy. After measuring in viscous samples, the electrode should be washed repeatedly with hot deionized water to remove the sample stuck to the glass film, or cleaned with a suitable solvent first, and then washed with deionized water to remove the solvent.

6. After long-term use, the electrode will become passivated due to a decrease in sensitivity gradient, slow response, and inaccurate readings. At this time, the lower end of the electrode can be soaked in a 0.1M * solution for 24 hours (0.1M * preparation: 9ml hydrochloric acid diluted to 1000ml with distilled water), and then soaked in a 3Mkcl solution for a few hours, or soaked in 4% HF (hydrofluoric acid) for 3-5 seconds, washed with distilled water, and then soaked in a 3Mkcl solution for several hours to restore its performance.

7. Glass bulb contamination or liquid interface blockage can also cause electrode passivation. At this time, appropriate solution cleaning should be carried out according to the properties of the pollutant, as shown in the table below. (For reference only)

Pollutant: Cleaning agent:

Inorganic metal oxides below 1M*

Organic oil-based detergent (weakly alkaline)

Resin polymer substances such as dilute alcohol, acetone, and ether

Protein hemocyte sediment acidic enzyme solution (such as *, etc.)

Pigments release bleach and hydrogen peroxide

8. The usage cycle of the electrode is about one year, and it should be replaced with a new electrode in a timely manner after aging.