Releasing of promethazine hydrochloride from various materials

The aim of this study to investigate the release of a cationic drug, Promethazine hydrochloride (PHCl) from varous hard and soft materials. The releasing of Promethazine hydrochloride (PHCl) from two clays (KSF and iron rich smectite, IRS) and three hydrogels (ChitEPI400, ChitEPI600 and ChitEPI800) was investigated in pH=1.2 and pH=7.4. From the release study, the maximum amount of PHCl released from KSF is almost %56.8 of the total in the range studied (0-540 min) at PBS. Release of PHCl from KSF, in acidic solution is less than 1%. Releasing of PHCl from IRS was 14.5 % at 715 min at pH=7.4. Besides, there was very little release from IRS (lower than %1.2) in acidic medium (pH=1.2). The hydrogels were synthesized by using Chitosan crosslinked by epichlorohydrin (EPI) at various amounts( 400, 600, 800 ?L). SEM, FTIR and DSC analysis were conducted. Swelling behavior of Chitosan-EPI hydrogel film is pH dependent. Furhermore, when the pH values were changed repeatedly, ChitEPI hydrogel showed a reversible swelling behaviour with a fast response. The release of PHCl from synthesized hydrogels at pH 7.4 was quite low. Only about 10 % of the loaded drug was released during 600 min for all hydrogels. Considering PHCl release at pH 1.2 the highest value was observed as 49 % for ChitEPI600. As a conclusion , KSF may be a suitable carrier for PHCl releasing in pH=7.4, however ChitEPI hydrogels can be used for the delivery of drug which will be released in stomach and gastrointestinal tract.