Lindholm blood coagulation test values of some glow-discharge polymer surfaces

An ultrathin layer (approximately 500A) of glow-discharge polymer that is strongly bonded to a polymer film substrate can be sued to modify the blood compatibility of the polymer surface. Glow-discharge polymers of tetrafluoroethylene, hexamethyldisiloxane, ethylene-N2, and allene-N2-H20 were deposited onto Mylar film and subjected to Lindholm whole blood coagulation tests. Lindholm tests were performed in a manner that permitted statistical analysis. This was done by repeating the preparation of samples as well as the coagulation tests a number of times. Results showed that Lindholm tests values were useful in obtaining information pertinent to compatibility of surfaces with fresh human blood and to reproducibility of sample preparation by glow-discharge polymerization. The study also revealed that glow-discharge polymerization is a promising method to impart blood compatibility without altering other bulk properties of substrate polymers.