Passage time measurement of individual and blood cells through arrayed micropores on Si 3N 4 membrane

Abstract

A new system has been developed for determining the deformability of individual red blood cells (RBCs), simulating the passage of RBCs in capillaries. The kernel of this system was the micropore array filter with an accurately defined pattern made by semiconductor microprocessing techniques. Individual microscopic RBC images were processed in parallel through a microcomputer and its interfacing circuit. An experiment with a normal RBC from a human donor demonstrated that it could pass the circular pore filter with a diameter as small as 1.0 μm at 2 cm H 2O pressure difference. Deformability of RBCs treated with diamide or acetylphenylhidralazine was also measured, showing that the system was sufficiently sensitive to detect the deformability loss due to membrane damage or to polymerization of the cytoplasma.