Adsorption-desorption of ondansetron on latex particles

Ondansetron is a carbazol with antiemetic properties. It is used primarily to control nausea and vomiting caused by cytotoxic chemotherapy and radioth erapy, as well as for treatment of postoperative vomiting in gynecological surgery. Ondansetron has a shelf life of about 3 hr; hence, it is a matter of great interest to determine the ideal adsorption-desorption conditions f or this drug on Inter particles for designs of formulations (oral suspensio ns) containing polymers with the aim of delivering different drugs in a pro longed and controlled fashion. Time, pH, electrolytes, and concentration of the active principal at which maximal adsorption occurred were determined Desorption of the drug from Eater polymer particles was studied in differen t media. The results obtained suggest that this polymer is suitable as carr ier of drug for obtained formulations of controlled release. The findings s uggest that pH is the principal factor influencing the release of the ondan setron from Aquateric(R). The greatest release of drug occurs at acid pH, a pproximately 70% in the first hour; for the basic medium, the release is ab out 6%.