A MICROCHANNEL FOR IN VITRO IMAGING OF ERYTHROCYTE SHAPE TRANSFORMATIONS BY VIDEO MICROSCOPIC TECHNIQUE

Summary An in-house fabricated microfluidic channel was developed using easily available materials (glass slide, transparency shapes, polyvinyl chloride tubes, coverslip, and epoxy) and manual positioning techniques with the aid of a profile projector, in the absence of other fabrication facilities. 2,3,11–15 Despite the limitations of being less accurate and more laborious, manual methods offer an easy, inexpensive, and readily implementable alternative to automated ones. Being economical, they enable testing of newer models and hypothesis, development of new designs, and trail stage/prototype experimentation. Once the effectiveness of the developed channel is established, the manual fabrication method can eventually be automated. So far as erythrocyte deformability is concerned, the microchannel thus fabricated enabled multishape erythrocyte deformability analysis in contrast to the unishape approach by earlier studies. 11–15,19 Though the microchannel in this study has larger width (30 μm) compared to the mean RBC diameter (~8 μm), it allows free orientation of cells and larger variation of shear condition across the channel cross section. Consequently, both asymmetrical and axial shapes were observed during the flow. Hence, it may be concluded that a larger cross section and medium to high flow (10–20 mm/s) may be appropriate for multishape characterization of erythrocytes in dilute suspensions. The issue of determining the DI for several deformed shapes and sorting them from other interacting and nondeforming RBCs could be handled with more flexible software techniques.