Flow cytometric analysis by using micro-machined flow chamber

Effect of the flow characteristics in a newly developed micro-machined shea th flow chamber on the accuracy of cytometric analysis was investigated. Th e chamber was formed by laminating three 100-mu m-thick photo-etched metal plates. Sample fluid containing cells, which enters the chamber via an axia l specimen nozzle, is enveloped by a buffering sheath-fluid and transported to a capillary channel. Microscopic observation and three-dimensional visc ous flow analysis predict that the dispersion of cells in the capillary cha nnel is favorably reduced when the Reynolds number is between 500 and 750, which is value associated with low deviation of the analytical results. The five classifications of human white blood cells were determined, and this verified that change of the deviation depends on the Reynolds number. The r esults confirm Reynolds number of 500 - 750 is appropriate for good classif ication.