[Plasma prekallikrein activation by highly dispersed organic silica].

Human and animal blood plasm precallikrein was studied as activated by the high-dispersed preparations of silica (aerosils) which carry on their surface various chemically grafted organic radicals. It is shown that hydrophilic silica containing -COOH, -HN2, -OH groups, contrary to the hydrophobic ones, are efficient in activating human plasm precallikrein. Precallikrein activation is dependent on concentration of hydrophilic aerosil, temperature and specific surface of the activator.