Gram Staining

목차

1. Objective
2. Introduction & Background
1) Biological staining
2) Types of staining techniques
3) Gram staining
4) The principle of gram staining
3. Apparatus
4. Reagents
5. Procedure
1) Smear of bacteria
2) Staining
6. Cautions
7. Results
8. Discussion

본문내용

thing.
95% ethyl-alcohol
1) General
- Synonyms : ethanol, grain alcohol, fermentation alcohol, alcohol, methylcarbinol, absolute alcohol, absolute ethanol, anhydrous alcohol, alcohol dehydrated, algrain, anhydrol, Cologne spirit, duplicating fluid 100C, ethyl hydrate, ethyl hydroxide, jaysol, jaysol s, molasses alcohol, potato alcohol, sekundasprit, spirits of wine, spirit, synasol, tecsol
- Molecular : C2H5OH
- CAS No : 64-17-5
- EC No : 200-578-6
- Annex I Index No: 603-002-00-5
2) Physical and Chemical data
- Appearance : colourless liquid
- Melting point : -114 C
- Boiling point : 78 C
- Molar mass : 46.07 g mol1
- Density : 0.789 g cm-3
- Specific gravity: 0.789
- Vapour pressure: 1.59
- Flash point : 14 C (closed cup)
- Explosion limits : 3.3% - 24.5%
- Autoignition temperature : 363 C
- Water solubility : miscible in all proportions
3) Stability
- Stable. Substances to be avoided include strong oxidizing agents, peroxides, acids, acid chlorides, acid anhydrides, alkali metals, ammonia, moisture. Forms explosive mixtures with air. Hygroscopic.
4) Toxicology
- Causes skin and eye irritation. Ingestion can cause nausea, vomitting and inebriation; chronic use can cause serious liver damage. Note that "absolute" alcohol, which is close to 100% ethanol, may nevertheless contain traces of 2-propanol, together with methanol or benzene. The latter two are very toxic, while "denatured" alcohol has substances added to it which make it unpleasant and possibly hazardous to consume. Typical OEL 1000 mg/m3.
5. Procedure
1) Smear of bacteria
Wash the slide glass and dry it. And Sterilize loop using alcohol lamp and lower temperature of loop to 40°C. Pick out single colony using loop and smear on the glass. Fix the cells on the slide glass with flame. 미생물학 실험서 / 한국미생물학회 편 /을유문화사, 1998.
2) Staining
Staining the specimen with crystal violet. stand for 1min and wash the slide glass. Staining the specimen with iodine. stand for 1min and wash the slide glass . Decolorize with ten 95% ethly-alcohol. stand for 10~20 sec and wash the slide glass. this process is very important thing. we must keep a decolorization time. If decolorization time is too long, positive bacteria can appear negative. On the other hand, if decolorization time is too short, negative bacteria can appear positive. And staining the specimen with safranine. stand for 45sec and wash the slide glass. The last, we have to use the optical microscope and observe the bacteria. Chemical Engineering Laboratory Ⅱ - SungKyunKwan Univ. Chemical Engineering
6. Cautions
Error in experiment
First, over heat when you fix cells
Decolorization too long time
Powerful washing => even gram-positive can be looks like gram-negative because it loss it’s complex
Bacteria’s characteristic
Gram-positive has different capacity to hold complex in the cell,
therefore some bacteria can turn into gram-negative when it loss the complex easily. 생물학 실험 / 김선희 등저 /제2판 /고려의학, 1994.
7. Results
8. Discussion

키워드

화학공학실험,   화공실험,   gram staining,   그람 염색법