Analysis of the coagulation of human blood cells on diamond surfaces by atomic forcemicroscopy

Abstract

Atomic force microscopy (AFM) was used to study the morphology and coagulation ofhuman blood cells in contact with solid surfaces. Blood was extracted from the veins ofhealthy adult donors and the samples were used immediately after extraction,deposited either on borosilicate glass or diamond substrates. Some blood samples wereanti-coagulated by adding heparin for single cell AFM imaging. No chemicals were used forattaching or immobilizing the cells. The diamond substrates were produced by chemicalvapour deposition (CVD diamond) using a hot-filament CVD system fed with ethanolhighly diluted in hydrogen. AFM imaging of isolated cells (anti-coagulated byheparin) was only possible on the glass substrates due to the lack of adherenceof the cells to the diamond surface. The coagulation results suggest that bloodclotting on diamond produces a less rough surface than blood clotting on glass.