An apparatus and method for concentrating and measuring low levels of cells
in biological samples. The apparatus, or concentration device, consists of
two chambers with an optically level collection membrane intermediating
between the chambers. The collection membrane filters the biological
sample, trapping cellular elements of interest. A vacuum may be attached
to the device to assist in filtration. The surface area of the collection
membrane matches the view field of a standard imaging system and the
device can be mounted on a standard microscope stage. All the cells in the
sample volume are collected onto the membrane. The view field provides a
fixed volumetric area for cell counting. Since the volume of sample tested
is known, the total number of cells in the original sample may be
calculated. The sample reservoir of the concentration device may also be
used for sample preparation. The concentration device is fully-contained;
therefore, the investigator does not have to handle the sample once it is
placed in the sample reservoir.
