Red blood cell sorting with a multi-bed microfabricated filter

A microfabricated fluidic chip for sorting red blood cells (RBCs) by size has been designed, fabricated and tested. The performance of the chip has been compared against a flow cytometer using samples from identical populations of cells, and statistically significant (p < 0.0005) differences in the measured cell size distributions were observed. The measurement paradigm reported here differs from previously demonstrated devices such as microfabricated Coulter counters or flow cytometers, in that the analysis is inherently parallel and is thus suitable for high throughput, point-of-care analysis. This study is empirical and semi-quantitative. However, important features of RBC trapping are characterized and indications for improved device design are described.