Sedgewick-Rafter And Cover Glass
The cell can be used with either living or preserved material. To fill the cell, place the cover glass across the chamber top. This allows the air bubbles to escape during the filling procedure. The sample is then taken into a 1ml wide mouthed pipette and then carefully transferred to the chamber. Do not overfill the chamber, because the volume of the sample in the chamber must be known exactly and the cover glass must not float free, but held onto the cell walls by surface tension. During counting, water may evaporate from the chamber. To prevent glass bubble formation, a small drop of distilled water may be placed on the slide outside the cell, just touching the cell wall and cover glass. Before the cell count is made the Sedgewick-Rafter chamber should be allowed to stand for at least 15minutes to allow algae, or other particles to settle to the bottom.
The grid pattern in the base of the chamber assists the counting and calculation process by clearly defining a known sample volume in 1ul blocks.
Counting in strips is easier, no need to use reticle grids or know the precise area of your field of view.
The makes the EMS S50 & S52 Gridded Sedgewick-Rafter Cell perfect for use with a stereo zoom microscope without the need to carefully set the precise zoom/magnification before counting the sample.
For precise sample preparation and calculation methods, you should follow your own internal or published procedures.
To clean the counting chamber: after completing the count, remover the cover glass and clean the counting chamber with water or a mild cleaning solution (10% solution of bleach). Dry the counting chamber with a soft cloth or wipe, or rinse with acetone.