Utensils commonly used in microbiology laboratories

glassware used in
microbiology laboratories are mostly disinfected, sterilized and used to
culture
microorganisms, so their quality, washing and packaging methods have certain requirements. Generally speaking, the quality of glassware requires hard glass, in order to withstand high temperature and brief burning without breaking, the free alkali content of the utensils should be less, otherwise it will affect the acidity and alkalinity of
medium
These aspects are described in more detail in this section.I. Types, requirements and applications of utensils
1. Glass test tubes used in the test tube
microbiology laboratory must have a thicker tube wall than chemistry laboratory, so that when stuffing cotton plugs, the tube mouth will not break. The shape of the test tube requires no rupture, otherwise, microorganisms can easily enter the test tube from the gap between the cotton plug and the tube mouth and cause contamination. In addition, there are now test tube caps made of aluminum or plastic without cotton plugs, and it is not convenient to cover test tube caps if you use a rummage test tube. Some experiments require to minimize moisture in the evaporative test tube, the use of screw test tube, cover with screwwood or plastic cap.
test tubes can be prepared in the following three models depending on the purpose.
(1) large test tube (about 18×180mm) can fill the media used in petri dishes, or can be used to prepare
agar fat
slope (when a large number of bacteria are required).
(2) TEST tubes (approximately 13-15×100-150mm) contain liquid mediums or agar slopes, which can also be used for dilution of viruses and
serum
tests.
(3) small test tubes (10-12×100mm) are generally used in sugar fermentation or serological tests, as well as other tests that require
2. Durham tube
When observing the gas production of bacteria in a sugar fermentation media, a small inverted sleeve (approximately 6×36 mm) is usually placed in a small test tube, also known as a fermentation tube×
3.The straw (also known as pipette)
(1) glass pipette microbiology laboratory typically prepares 1, 5, 10 ml of tick glass straw. Unlike those used in chemical laboratories, the volume indicated by the scale often includes the volume of the liquid at the tip of the tube, i.e. when using, care should be paid to blowing out the absorbed liquid, so it is sometimes referred to as "blowing out" the straw. Commercially available bacteriology straws, some with the word "blow" engraved on the upper end of the straw.in addition to scaled straws, sometimes need to use non-metered capillary straws, also known as droppers, to absorb animal body fluids and centrifugal liquid, as well as droplets plus a small amount of
antigens
,
antibodies
and so on.(2) piston pipette is mainly used to absorb trace amounts of liquid, so it is also known as trace suction or microscope. Its shape and structure, as shown in I.-4, in addition to the plastic housing, the main components are buttons, springs, pistons and handlable nozzles. Press the button to move the piston up and down through the spring to suck in and release the liquid. It is characterized by fixed capacity, when used without observing the scale, easy to operate, fast. Domestic products generally each piston straw fixed a capacity, respectively, there are 5, 10, 20, 25, 50, 100, 200, 500, 1000 sl and other different capacities. The refined piston straw each can adjust several volumes within a certain range, for example, in the range of 5-25 μl, adjustable 5, 10, 15, 20, 25 sl five different amounts, when used as needed, but when the adjustment is fixed, each suction, the capacity is still fixed. Simply change the nozzle or wash the nozzle, disinfect it and use it.piston straws were only produced and applied in the second half of the 1970s abroad, and in recent years they have been widely used in immunology and the use of isotopes in scientific experiments.4. Petridish is a commonly used
dish with a diameter of 90mm and a height of 15mm. Petri dishes are generally glass lids, but when there is a special need, you can use the ceramic lid, because it can absorb moisture, so that the surface of the culture base
driding
, for example, when determining the biological property price of antibiotics, petri dishes can not be inverted culture, then the ceramic lid is good.
pours an appropriate amount of solid media into a Petri dish to make a plate for separation, purification, identification of strains, microbial counting, and determination of the effectiveness of antibiotics, phages, etc.5. Triangle flasks (Erlenmeyerflask) and beaker
triangle flasks are 100, 250, 500, 1000 ml and other different sizes, often used to contain sterile water, medium and bottle fermentation. Commonly used berries are 50, 100, 250, 500, 1000 ml, etc., used to make cultures and medicines.6. Syringes (injector)
usually have syringes of different capacities such as 1, 2, 5, 10, 20, 50 ml. Injection antigens can be used in animals with 1, 2 and 5 ml as needed, and 10, 20, 50 ml can be used to extract animal heart blood or sheep vein blood.
trace syringes are 10, 20, 50, 100 sl and other different sizes. It is generally used when dripping with trace samples in experiments such as immunology or paper analysis.7. Slides and cover slides
Normal slides are 75×25 mm in size for microbial smearing, dyeing, morphological observation, etc. The cover glass is 18×18 mm.
concave slide is a round concave nest in the center of a thick slide for dangling drops to observe live bacteria and micro-chamber culture. 8． Double bottle
consists of two glass bottles inside and outside, the inner small conical bottle is rich in balsamic tar, for oil lens observation of microorganisms, the outer bottle is contained xylene, to wipe the oil lens. 9. Droper bottles are used
various dyes, physiological saline, etc. 10. Vaccination tools
Inoculating tools include inoculating ring, inoculating needle (inocula-ting needle), inoculating hook, inoculating shovel, glass spreader, etc. Metals made of rings, needles, hooks, shovels can be used in platinum or nickel, the principle is soft and hard moderate, can withstand repeated burning of fire, and easy to cool. Inoculated bacteria and yeasts with inoculation rings and needles, the diameter of the platinum or nickel wire is appropriate at 0.5 mm, the inner diameter of the ring is about 2 mm, the ring surface should be flat. Inoculation of certain non-easily separated from the culture base of the linewom bacteria and fungi, sometimes with inoculation hooks or inoculation shovels, the diameter of its silk requires a thicker, about 1 mm. A glass coater is required to separate individual bacterios on a agar plate by coating method, which is made by bending the glass rod or flattening one end of the glass rod after it has been burned red. , glassware cleaning method
clean glassware is a prerequisite for the correct results of the experiment, therefore, glassware cleaning is an important preparation before the experiment. The cleaning method varies according to the purpose of the experiment, the type of utensils, the items stored, the type of detergent and the degree of contamination. The following is heeded: 1. Washing method of new glassware
newly purchased glassware contains more free alkali, should be soaked in acid solution for several hours first. Acid solutions are generally made with 2% hydrochloric acid or washing-up fluid (see section "3"). Rinse with tap water after soaking. 2. Used glassware washing method
(1) Test tubes, petri dishes, triangular berries, berries, etc. can be washed with bottle brushes or sponges with soap or detergent or detergent, etc., and then rinse thoroughly with tap water. Hot soapy water is more de-fouling and effectively washes away oil from the vessel. Laundry powder and detergent are more difficult to rinse clean and often attach a layer of tiny particles to the wall, so use water many times or even more than 10 times to fully rinse, or can be shaken with thin hydrochloric acid once, then rinsed with water, and then poured into a wire frame or a hollow grid of wooden racks, drying indoors. In case of emergency, it can be built in a box or on a enamel plate and dried in the oven. glassware after washing, if the inner wall of the water is evenly distributed into a thin layer, indicating that the scale is completely washed, if hung with water droplets, you also need to use washing liquid soaked for several hours, and then fully rinsed with tap water. a vessel containing a solid culture base should be scraped off before washing. The sterile utensils are immersed in a 2% kerosene soap solution (Lesul) or 0.25% neo-sterilizing liquid for 24 hours or boil for half an hour before washing, then wash with the method. Cultures with pathogens are best sterilized by high-pressure steam before the culture is reversed and then washed.
the utensils used in the general culture base can be used after washing, if the need for precise preparation of chemicals, or scientific research for accurate experiments, requiring tap water to be flushed clean, and then washed with distilled water three times, dry or dry after standby. (2) Glass straw sucks blood, serum, sugar solution or dye solution, such as glass straw (including capillary straw), after use should be immediately put into a tube containing tap water or specimen bottle, so as not to dry after difficult to rinse clean. The bottom of the barrel or specimen bottle should be cushioned with skimmed cotton, otherwise the straw will break easily when put in. When the experiment is complete, rinse it centrally. If the top of the straw is stuffed with cotton, then before flushing the tip of the straw and the rubber pipe mounted on the tap, wash the cotton out with water, and then load the straw automatic scrubber to rinse, no straw automatic scrubber laboratory can flush out cotton method for a few more moments. Wash with distilled water if necessary. After washing, let the enamel plate dry, to speed up the drying, can be put in the oven to dry. straws containing microbial cultures should also be immediately put into a solution containing 2% coal phenol soap or 0. 25% of the new sterilizing liquid in the barrel or specimen bottle, 24 hours before removal and rinse. the inner wall of the straw, if there is oil scale, it should also be soaked in the washing-up liquid for several hours before washing. (3) slides and cover slides used slides and cover slides such as a drop of balsamic tar, first wipe off with wrinkled paper or soaked in xylene shake a few times, so that the oil scale dissolves, then boil in soapy water for 5-10 minutes, wipe with soft cloth or skimmed cotton, immediately rinse with tap water, and then soak in thin detergent 0. 5-2 hours, tap water wash away the washing liquid, and finally with distilled water for several times, after drying soaked in 95% alcohol to save spare. Burn alcohol on the flame when using. Wash and save the slides and cover slides in this way to clean and shine without water drops.
to check the live bacteria of the slide or cover slide should first in 2% coal phenol soap solution or 0. Soak for 24 hours in 25% of the neo-dill solution, then wash and save according to the method. 3. The preparation of the washing liquid and the preparation of the washing solution using
(1) washing liquid are two kinds of thick solution and the thin solution, the formula is as follows:
thick solution heavy sodium chromate or potassium heavy chromate (industrial) 50 g
tap water 150 ml
thick sulfuric acid (industrial) 800 ml
sparse solution Sodium heavy chromate or potassium heavy chromate (industrial) 50 g
tap water 850 ml
strong sulphuric acid (industrial) 100 ml the method is to dissolve sodium chromate or potassium heavy chromate in tap water first, can be slowly warmed, so dissolved, cooled and slowly added to the sulfuric acid, while stirring. the washing-up liquid should be brown or orange. Store in a covered container.
(2) principle Sodium dichromate or potassium dichromate and sulfuric acid after the formation of chromic acid (chro-mic acid), tyric acid oxidation capacity is very strong, so this liquid has a very strong de-fouling effect.
(3) Use note
(a) Sulphuric acid in the washing liquid has a strong corrosive effect, glassware soaking time is too long, will cause the glass to go bad, so avoid forgetting to remove the vessel and rinse. Second, if the washing liquid stained clothes and skin should be washed immediately with water, and then washed with soda or ammonia. If splashed on tables and chairs, wash it off immediately or wipe it off with a damp cloth;
(b) the glassware should be as dry as possible to avoid dilution of the washing-up liquid before it is put in;
(c) the use of this liquid is limited to glass and porcelain vessels and does not apply to metal and plastic vessels;
(d) there is a large amount of organic matter of the vessel should be scrubbed first, and
then with washing liquid, because of too much organic matter, will speed up the failure of the washing liquid, in addition, the washing liquid is a strong detergent, but not all stains can be removed
; , empty glassware packaging
1. Petri dishes packaging
Petri dishes are commonly used in old newspapers tightly packed, generally 5-8 sets of petri dishes as a package, less than 5 sets of work is too large, more than 8 sets of difficult to operate. Pack and then go to thermal sterilization. If a Petri dish is placed in a copper cylinder for dry thermal sterilization, there is no need to use paper bags, the copper cylinder has a cylinder-shaped covered outer cylinder, which contains a petri dish with a bottom frame, this frame can be raised from inside the cylinder, in order to load the Petri dish. <br/