Abstract
Polypropylene (PP) disks activated by exposure to ammonia glow discharge were used as substrates for red cells deposited from saline suspensions. In some cases these cell-coated disks were further treated by glutaraldehyde to bind the cells more strongly. Each disk was used in a rotational blood-shearing device to induce hemolysis, which was compared with that induced by virgin PP. When the cell coating was uniform and dense from a single settling of cells, the glutaraldehyde-fixed surfaces were about 10% less hemolytic than PP. Non-fixed cells detached from outer regions of the disk and apparently contributed additional hemolysis in the process. Secondary layers of settled cells, both fixed and non-fixed, also proved to be more hemolytic than PP. Coatings of γ-globulin reduced hemolysis relative to uncoated cell surfaces. The best performance was that of activated surfaces without cells, with hemolysis about 20% less than PP. Tests of cells hemolyzing during detachment in a saline medium suggested that hemolysis of whole blood involves a series of brief attachment/detachment events at the solid surface.