Sustained delivery of aspirin by means of ALCAP ceramics.

Research conducted at the University of Dayton has shown that alumino-calcium-phosphorous (ALCAP) ceramics impregnated with polylactic acid (PLA) are capable of sustained delivery of polypeptides and steroids. Recent experiments conducted at the university have shown that ALCAP ceramics are capable of delivering aspirin in vitro. Based on this work, ALCAP ceramics containing 25 mg, 50 mg, or 75, mg aspirin were implanted subcutaneously in random bred albino male rats. There were eight rats in each dosage group. Six rats were implanted with empty ceramics (sham-operated). Eight nonimplanted rats served as controls. Levels of analgesia among the groups were determined using a pressure analgesia meter. The data collected showed that aspirin delivered by ALCAP was capable of producing analgesia in rats as early as 24 hours after surgery. The level of analgesia increased over the first seven days before declining gradually over a period of one month. Levels of analgesia were directly related to the amount of aspirin stored initially within the ceramic.