High aspect ratio submicron channels using wet etching. Application to the dynamics of red blood cell transiting through biomimetic splenic slits
Résumé
During splenic filtration, disseminating cancer cells and red blood cells (RBCs) must deform through submicron wide interstices, between blood vessels’ endothelial cells. The dynamics of this process remain poorly understood because the in vitro reproduction of slits with physiological dimensions in transparent devices had not been achieved.
Here, novel microfluidic PDMS devices containing high aspect ratio slits with physiologically relevant dimensions (especially submicron width) were fabricated using an inexpensive and highly flexible fabrication method combining standard UV-lithography and anisotropic wet etching of (110) silicon.
Novel modes of RBCs deformations were revealed using our devices: the membrane of spherocytic RBCs seemed transitory dissociated, while healthy and sickle cell disease RBCs exhibited peculiar tips at their front, the dynamics of which was linked to cytoplasmic viscosity.