Preparative Technology of Medium in Microbiology Lab

In the process of preparing medium in microbiology lab, some glassware should be used first, such as test tube, triangle bottle, culture dish, beaker and straw, etc. These utensils should be treated and cleaned according to different situations before using. Some need to be packed and sterilized before using.

1. New glassware

After removing the dirt from the package, first brush it with hot soapy water, rinse it with running water, and then soak it in 1-2% industrial hydrochloric acid for several hours to remove the free alkaline substance, and then rinse it with running water. For vessels with large capacity, such as large flasks, measuring cylinders, etc., after cleaning, inject a little concentrated hydrochloric acid, rotate the container to make its internal surface uniformly stained with hydrochloric acid, after a few minutes, pour out hydrochloric acid, then wash it with running water, turn it upside down on the washing rack and dry it with air, then it can be used.

2. Used glassware

If there is no pathogenic bacteria or the vessel is not polluted by bacteria, it can be washed at any time after using. The straw that has absorbed chemical reagent can be soaked in clear water first, and then cleaned in a certain amount. Utensils that may be contaminated by pathogenic bacteria must be properly disinfected to remove the dirt, washed with soap solution, and then rinsed with running water. If the utensils are not cleaned with soap solution, they can be soaked in the solution for a proper time and then washed with water. The main components of the lotion are potassium dichromate and concentrated acid. Its function is to oxidize organic matters into soluble substances for washing. The lotion has a strong corrosive effect and should be used with special care to avoid splashing on clothes, body and other items.