University:
Duke University
Course:
BIOLOGY20 | General Biology
Academic year:

2024
Views:

182

Pages:

2
Author:

Rebecca B.

CARE / MAINTENANCE OF GLASS EQUIPMENT I. General washing of glassware III. New glassware: New welding tools are usually somewhat alkaline. To neutralize the glassware, soak it in 2% HCL solution for 24 hours. Next, wash twice with tap water and rinse with aqua destillata, then dry. IV. Dirty glassware a. The remaining material in the container is discarded. If material is considered to be infectious, such as feces, spuntum, CSF, pus, blood, urine and media containing germ cultures, then the material must be destroyed first.Digestion can be carried out using an autoclave at a temperature of 101o C for 30' or boiled in detergent solution for 30'. b. The tool is then washed twice with cold or warm water. If not washed immediately, glassware should be soaked in water so that it does not become dirty. Continue washing using a detergent solution and clean the inside of the glass (if possible) using a tube brush. c. Wash the glass with running water then rinse with aqua destillata. Place the glassware on the shelf with theo mouth at the bottom. For non-measuring glassware, it can be dried in the oven at 60 C. V. Greasy/contaminated glassware with materials that are difficult to remove: a. The glassware is first soaked in a strong or corrosive acid solution, for example a fuming chromic acid or sulfuric acid solution overnight. b. Next, wash it like dirty glassware. VI. Glass objects that are new or contain immersion oil: The glass object is soaked in a detergent solution overnight. Wash with running water for 15 minutes, wipe one by one with a soft cloth or tissue paper then dry. II. Removes hard-to-clean contaminants To remove sediment/contamination that is difficult to clean, the following recommendations can be followed: a. Carbon tetrachloride or other empera solvents are used to remove fat and grease. b. Ammonia or hot hydrochloric acid, a mixture of concentrated sulfuric acid and nitric acid is used to remove albumin or glucose stains c. A concentrated solution of chromic acid or sulfuric acid containing 0.5% potassium nitrate or perchlorate is used to remove stains from empera materials by soaking the glassware overnight. d. Hot concentrated hydrochloric acid with potassium chlorate to remove copper or iron oxide stains. e. Hot sulfuric acid to remove barium sulfate deposits. f. Ammonia or sodium thiosulfate to remove Silver nitrate deposits. III. Use of glassware with heating or cooling a. Always follow the manufacturer's instructions when using an electric heat source b. Do not leave the glass vessel while evaporating, because the vessel can crack or explode when the vessel is close to dry. c. Glassware should not experience sudden changes in temperature from hot to cold or vice versa, because this can cause the glassware to break. d. Heating glassware is carried out using heat that is spread with asbestos metal mesh or a water bath, so that the heat moves slowly from the heat source of the glassware. e. Boil the liquid in the vessel quickly and evenly, then anti-symptomatic materials such as pumice or boiling stones can be added to the vessel. f. Heating the liquid in a test tube using direct fire is done in the middle of the tube so that the heat can spread evenly when heating, the mouth of the tube is directed to a part where no one is present.