Abstract
The numbers of radicals generated in binary powders of glycolic acid and silicaalumina and of potato starch and silica-alumina determined by means of electron spin resonance (ESR) were found to be affected by mechanical energies. For example, the numbers of spins increased with increase in the shaking duration, with increase in the compressive stress, and with decrease in the size of particles. The numbers of radicals were also influenced by the techniques used for mixing the binary powders. An increase in the number of radicals induced by mechanical forces may increase the rates of chemical reactions during the manufacture and storage of drugs.