Whole-Blood Diagnostic Sensing System Based on Populational Platelet Rolling Behavior

<jats:p>We are developing a point-of-care diagnostic sensor system for early warning of diseases or disorders involving the activation state of platelets. The system tracks platelet movement-adhering, releasing, rolling-along a well-characterized protein surface using customized image analysis to objectively quantify fluid-shear-mediated platelet-surface interactions for statistically meaningful numbers of platelets from a single blood sample. The fluidic device provides well-defined shear at the surface at physiological rate (~ 1500/s) and hydrodynamically focuses the sample stream into contact with the surface, providing assay results from < 200 µL of undiluted whole blood. Frame-by-frame object tracking of translocating platelets provides individual trajectories via a position-based probability function. Initial results show the relative fraction of time spent by platelets in the mobile relative to the stationary state is approximately 1.6 times longer for blood treated with abciximab (ReoPro) than for untreated normal blood.</jats:p>