Important: The metallised surface of the counting cell is delicate. It is composed of metallic Rhodium - a few atoms thick - fused into the glass surface.
Cleaning: Great care should be taken not to scratch this surface either with capillaries in use or by abrasion whilst cleaning. Never rub or brush the chamber. Clean by immersion in warm water or in the most dilute solution of a neutral detergent cleanser. Sterilisation prior to cleaning may be by immersion in alcohol, if suitable, or by immersion in a 2% solution of glutaraldehyde.
Method of use:
Total count: Allow 15-20 minutes for the semen sample to liquefy completely. Place 4.5µl of sample centrally on the counting chamber's metallised cell platform. This sample may be measured using a capillary pipette in conjunction with an aspirator. Dilution of the sample may be necessary if it is too viscous for pipetting and the factor of dilution; i.e. 1 in 2, 1 in 4 etc noted. If dilution is required the sample should be thoroughly mixed before pipetting. The coverslip is placed firmly over the counting chamber and the counting performed in the usual way, under a microscope typically of x 200 magnification. As the grid squares are 0.1 x 0.1mm and the depth of the cell 0.01mm, the volume of original sample corresponding to one square is 0.0001µl.
It is convenient practice to count the sperm cells in 10 squares and to multiply this count by 1 million for an undiluted sample or by 1 million times the dilution factor for a diluted sample. This provides a count of cells per milliliter.
Motility: Due to the fact that sperm cells are trapped in a mono-layer their motility is easily assessed as follows:
- Count the immobile cells in a suitable number of squares and then count the moving cells in the same square.
- Repeat this procedure a number of times and then calculate the average percentage motility.