ADHESION OF HUMAN PLATELETS TO COLLAGEN DETECTED BY CR-51 LABELING AND ACOUSTIC-WAVE SENSOR

Selective adhesion of human platelets to layers of collagen Type I, im mobilized on silicon wafers, has been confirmed using Cr-51 radiolabel ling of platelets. Corresponding experiments conducted with collagen-t reated thickness-shear mode acoustic wave sensors resulted in changes in series resonant frequency in the range 35-43 Hz. Control experiment s with sensors, coated with bovine serum albumin, displayed significan tly reduced response. Similar reduced values were also obtained when E DTA was present and Mg2+ was absent from the assay-buffer solution. Di rect correlation of the sensor results with Cr-51 labelling experiment s confirms that the conventional quartz crystal microbalance descripti on is completely inadequate to explain the magnitude of the sensor res ponse, which is 200 times less than that predicted by the well-known S auerbrey expression.