Improved Neubauer Counting Chamber
The Improved Neubauer Chamber is a thick glass slide with the size of 30 x 70 mm and 4 mm thickness. In an improved neubauer counting chamber, the central area is where the cell counts are performed.
The chamber has three parts:
(1) the central part, where the counting grid has been set on the glass, and
(2) double chambers/two counting areas that can be loaded independently.
Improved Neubauer chamber’s counting grid is 3 mm x 3 mm in size. The grid has 9 square subdivisions of width 1mm. In the case of blood cell counting, the squares placed at the corners are used for white cell counting. Since their concentration is lower than red blood cells a larger area is required to perform the cell count. The central square is used for platelets and red cells. This square is split in 25 squares of width 0.2 mm (200 µm). See Fig. 4-2. Each one of the 25 central squares is subdivided in 16 small squares. Therefore, the central square is made of 400 small squares.
How to use a Improved Neubauer Counting Chamber ?
To prepare the improved neubauer counting chamber the mirror-like polished surface is carefully cleaned with lens paper. The coverslip is also cleaned. Coverslips for counting chambers are specially made and are thicker than those for traditional microscopy, because they must be strong enough to overcome the surface tension of a drop of liquid. The coverslip is placed over the counting surface prior to putting on the cell suspension. The suspension is introduced into one of the wells with a pasteur pipette or other type of dropper. The area under the coverslip fills by capillary action. Enough liquid should be used so that the mirrored surface is just covered. The charged imrpoved neubauer counting chamber is then placed under the microscope and the counting grid graph is brought into focus at low power.