DelAgua OXFAM-DELAGUA, Руководство пользователя

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OXFAM-DELAGUA Water Testing Kit — Users Manual
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procedure takes 3 days. Place the bottles of culture medium into a cooking pot
or pan of boiling water, taking care to ensure that the bottles do not come into
contact with the base of the pan (use a rack or stand) or become submerged.
Boil for 20 minutes. Leave the medium to stand for 24 hours at room
temperature (20-30°C) in the dark. On the following day heat the medium in
boiling water for a further 20 minutes and, once again, leave to stand for 24
hours. On the third day repeat the heat treatment. The medium should now be
sterile.
3.4 Storage of Culture Medium
Sterile MLSB will be stable for up to 6 months if stored in a refrigerator (between
4 and 6°C). Alternatively, the medium can be stored for up to 3 months in a cool,
dark place. If the medium has been stored for several days below 6°C a deposit
may form which dissolves when the medium is warmed and gently shaken. The
deposit is caused by the lauryl sulphate coming out of solution.
If signs of deterioration are observed, eg. cloudiness or yellow colouration, the
contents of the bottle must be discarded.
3.5 Sterilising the petri-dishes
1.
Wash the dishes in a solution of mild detergent, rinse thoroughly with clean
water and dry.
2. Assemble the dishes into batches of 16 in the straps.
EITHER
3. Sterilise the petri dishes in an autoclave, steam steriliser or pressure cooker at
121°C for 15 minutes (see section 3.2 paragraphs 6 and 7).
OR
4. Place the dishes in a conventional oven at 180°C for 30 minutes.
OR
5. Plunge the bases and lids of the dishes into boiling water for 10 minutes. Pour
away the water and assemble the dishes as they dry, but while they are still
hot.
OR
6. Add a few drops of methanol (or ethanol) to a clean cloth and wipe the inside
of the lid and the base of each petri-dish. Assemble the petri-dishes and allow
the alcohol to evaporate before use.