Effect of the electret-blood contact time on the adhesion of human blood platelets.

The paper presents the results of research into the time characteristics of adhesion of platelets to the electret surface made from polyethylene terephthalate PET foil of 36 microns thickness. The electrets were formed by using the electron beam method. The method based on the electrostatic induction phenomenon was utilized to measure the electric charge surface density. Evaluation of the time characteristics of the adhesion of blood platelets was performed on the basis of microscopic examination and with the use of the chamber method for determining the number of blood platelets in the phase microscopy. The results obtained have confirmed the influence of the electret effect on PET foil thrombogenesis. The number of spacious aggregates found on the surfaces being analysed did not undergo any changes despite the extension of the electret--blood contact time. The stationary course of the adhesion process as well as the unappreciable amount of blood platelets on the surface have proved that the negative electric charge makes it possible to obtain thrombogenic materials.