This procedure was taught to me by Dr. Paul Bottino  in 1980 at the "Plant Cell and Tissue Culture" workshop offered by the Tissue Culture Association at the Alton Jones Cell Center at Lake Placid, NY. These filters can be used for cleaning small seeds, small explants, and for filtering suspension cultures and protoplasts.

This procedure should be conducted in an exhaust hood or under a kitchen exhaust fan due to the potentially toxic fumes given off by the melted plastic.

Cover the heating element of a hot plate with a double layer of foil, and turn hot plate setting on "High".

For kitchen labs, cover a small frying pan with a double layer of foil, and place on burner. Turn burner to medium.

Polyethylene bottles can also be used but cannot be sterilized in an autoclave or pressure cooker.

Cut a square piece of wire mesh large enough to fit over one cut end of the bottle.

Fuse the wire mesh to bottle by placing mesh on the hot surface and placing cut end of bottle on top, allowing the plastic to melt into the mesh. This happens very quickly so be sure to hold the plastic bottle and watch as the plastic melts into the mesh or fabric.

Remove from hot surface immediately and be sure that the plastic has melted and fused completely.

This surface will be very hot and can cause burns to the skin - do not touch.

After the plastic has cooled, trim corners of the mesh.

Cut the bottom off of the bottle and the filter is ready.

Remove from the bleach using a forceps. Place seed in the unit. Return the filter to the bleach solution and gently "dunk" the unit up and down so as to wet the seeds with the bleach. Do not immerse the unit in the bleach - the seeds might float out of the unit making handling impossible.

Samples of market grade stainless steel wire mesh can be obtained from Newark Wire Cloth Company, 351 Verona Avenue., Newark, NJ  07104, 800-221-0392. Ask for a sample of "market grade stainless steel wire mesh". A mesh size of 200 X 200 would be good. For specific mesh openings, see chart below. Mesh openings will differ between  manuafacturers. See specific charts for each company contacted.

25

.0010

500 x 500

61

.0024

250 x 250

73

.0029

200 x 200

104

.0041

150 x 150

140

.0055

100 x 100

280

.0110

50 x 50

520

.0203

30 x 30

860

.0304

20 x 20

1130

.0445

16 x 16