Laser light scattering studies from blood platelets and their aggregates

Platelets in plasma and in buffer have been studied using the static light scattering method. It has been observed that clustering of the platelets takes place in buffer whereas a feeble ordering occurs when they are in plasma. The structure factor for the fractal aggregates in buffer have been determined using an unweighted chi(2) fit of the observed scattered light intensity with the theoretically calculated intensity which assumes an exponential cut-off form for the cluster density correlation function. The fractal dimension (D-f) and the radius of gyration (R(e)) have been obtained from the chi(2) fit, assuming a gamma distribution for the polydispersity in the size of clusters. The values of D-f and R(e) are reported to be 2.2 and 26792.0 x 10-(10) m, respectively for the platelets without agonist and 2.11 and 41225.0 x 10(-10) m, respectively for the same with agonist. These values are in agreement with those reported by Latimer.