For preparing the onion tissue extract:
Liquidizer
Sharp vegetable knife and chopping board
Water bath set at 60oC
Ice, in a jug
Thermometer
250 cm3 beakers, 2
Coffee filter paper (do not use laboratory filter paper)
Onion, about 100 g
Washing-up liquid, 10 cm3 (do not use the thicker, concentrated type)
Sodium chloride, 3 g
Distilled water, 100
cm3
For separating the DNA from the onion extract:
Slender glass rod
10 cm3 syringe for measuring out liquids
Boiling tube Rack or small beaker for holding boiling tube
Onion extract (see below), 6 cm3
Protease enzyme, Novo Nordisk Neutrase, 4 drops
Ice cold 95% ethanol,
9 cm3
NOTE:
it is important to use this concentration of ethanol.
Place it in a freezer in a
plastic bottle overnight to ensure that it is ice cold.