Investigation of human blood platelets with fluorescence spectroscopy

Intramolecular excimer formation of dipyrenylpropane was investigated in human blood platelets. The ratio of the emission intensities of excimer to monomer (IE/IM) is sensitive to changes in lipidic membrane structure, induced by external perturbations, such as cholesteryl hemisuccinate introduction and temperature. Lack of reliable "microviscosities" determinations could be due to poor solubility of the probe in aqueous cells suspensions. Results were compared to those obtained with the fluorescence polarization technique.