1. Disinfection and cleaning of glassware
Treatment of newly purchased glassware Newly purchased glassware should be washed with hot soapy water, rinsed with running water, and then soaked in 1% to 2% hydrochloric acid solution to remove free alkali, and then rinsed with water. For large-capacity containers such as reagent bottles, flasks, or measuring tools, after washing with clean water, a small amount of concentrated hydrochloric acid should be injected, gradually rolling, so that the hydrochloric acid fills the inner wall of the container for a few minutes, then pour out the hydrochloric acid, and then rinse with water.
2. Handling of Contaminated Glassware
①Generally, the test tube or container can be soaked in 3% cresol soap solution or 5% shi carbonic acid and then boiled for 30 minutes. It can also be washed with soap or synthetic detergent to make foam as much as possible, and then washed with water until there is no soap. Then rinse with a small amount of distilled water.
②The test tubes and Petri dishes for bacterial cultivation can be concentrated first, sterilized by high pressure at 1kg/cm2 for 15 to 30 minutes, washed with hot water, washed with soap, and rinsed with running water.
③The straws should be soaked in 3% cresol soap solution for 24 hours after use and washed repeatedly with running water one by one, and then washed with distilled water.
④Utensils stained with oil and wax should be sterilized and washed by themselves. First, discard the oil-stained material, put it upside down on absorbent paper, dry it at 100°C for half an hour, then boil it with alkaline water, wash it with soap, and rinse with running water. When necessary, dijia benzene can be used to remove dirt.
⑤Utensils contaminated with dyes can be washed with water first, then washed with clean or dilute hydrochloric acid to elute the dyes, and then washed with clean water. Generally, the dyeing agent is alkaline, so it should not be washed with soapy water.
⑥The slides can be soaked in 3% cresol solution, taken out and rinsed with running water, then boiled with soap or weak alkaline, and after natural cooling, rinsed with running water. The slides contaminated with Mycobacterium tuberculosis or difficult to wash can be soaked in the cleaning solution and then rinsed.
3. Preparation of sterile equipment and liquids
After washing and drying the culture dishes, culture bottles, test tubes, straws, etc. in the glass utensils according to the above method, wrap the bottle mouth with a clean paper and plug the end of the straw with cotton, and put them in a clean aluminum box or iron box. , dried and sterilized in a drying oven at 120 °C for 2 hours, and taken out for use. For surgical instruments, corks, work clothes, and newly manufactured PBS washes, autoclaving was used, ie, heating at 15 pounds for 20 minutes. As for the MEM culture medium, calf serum, and digestive juice, needs to be filtered with G5 or G6 filter under negative pressure.
4. In the process of aseptic operation, it is important to adhere to the sterility and cleanliness of the operating area.
Therefore, 20 to 30 minutes before the operation, the ultra-clean table, and the ultraviolet lamp should be activated, and the hands should be washed and disinfected carefully. During operation, it is forbidden to make noise, and it is forbidden to directly hold sterile items, such as bottle stoppers, etc., but must use sterile hemostatic forceps, tweezers, etc. The incubation bottle should be operated on a clean bench, and the alcohol burner should be repeated when opening and capping the bottle. Regarding the straw, you should take it by hand at the back 1/3, put on a rubber ru tou, and use an alcohol lamp to grill before sucking the liquid.
5. Manufacturing method of common cleaning solution
①Dichromium Suan potassium cleaning solution: You can choose any of the following concentrations according to different needs. First dissolve potassium dichromate in water, and then gradually add concentrated sulfuric acid. Note that high heat can occur at this time and container rupture should be prevented. Dichromium Suan potassium cleaning solution has strong detergency and high corrosiveness, so avoid touching the skin and clothes. To prevent deterioration by absorbing moisture from the air, this liquid should be stored in a container with a lid. If the cleaning performance is poor, a small amount of potassium dichromate and concentrated sulfuric acid can be added, and it can be used continuously. Until the liquid turns blue-green, it can no longer be used. High temperature-resistant ceramic cylinders or acid-resistant enamel or plastic containers should be used in the manufacture of dichromium Suan potassium cleaning solution. When using glassware, special attention should be paid to prevent it from breaking due to high heat, and do not use a measuring cylinder to make it.
② Trisodium phosphate is formulated into a 5% to 10% aqueous solution, which can be used to wash the oil stains on glassware, but it is often used to corrode glass to make the surface of the wares fuzzy and rough.