Working w/ DNA and Storage Flashcards
- one of the best and simplest storage condition
5 C
- causes extensive single and double strand breakage
-20 C
- Optimal for longer (long-term) storage
-70 C
It is best to store in high salt (high Ethylenediaminetetraacetic acid pH 8.5)
- Storage of DNA in ______with______ in _______
buoyant Cesium Chloride
ethidium bromide at 50 C in dark
- Causes variety of lesions
- UV light at 260nm
- causes phosphodiester breakage
- Heavy metals
- Free radicals (formed from chemical breakdown and radiation)
- Oxidation products
- Avoid contact between finger and nucleic acids
- Nucleases (found in human skin)
- Stable and adsorb to glass or plastic (remain active)
- Ribonucleases
- Not stable
- Deoxyribonucleases
• can inhibit reactions or degrade nucleic acid.
Dirty test tubes, bacterial contamination and traces of
detergent
Glassware should be…
rinsed with distilled water and autoclaved or baked at 150C for 1 hour.
For experiments with RNA, glassware and solutions are treated with…
diethyl-pyrocarbonate to inhibit RNases which
is resistant to autoclaving.
tubes are turbid and are resistant to many
chemicals, like phenol and chloroform
Polypropylene
are clear and not
resistant to many chemicals.
Polycarbonate or Polystyrene tubes
are formed from
chemical breakdown and
radiation and they cause
phosphodiester breakage.
Free radicals
causes a variety of lesions.
Biological activity is rapidly lost.
UV light at 260 nm
causes photooxidation of DNA with visible light and molecular oxygen.
Ethidium bromide
Ethidium bromide is a mutagenic
substance that should be…
heat treated before disposal and
should be handled only with
gloves.
It should be disposed of in a labelled container.
Dirty glassware should be_______
Bottle caps, stir bars and spatulas
should…
rinsed
not be placed in the bins but should be washed with hot soapy water, rinsed well with hot water, and rinsed three times with distilled water.
Any media that becomes contaminated should be…
promptly autoclaved before
discarding it.
