Sodium alginate patches containing nicotine with different rate controlling membranes

Transdermal Sodium alginate patches containing nicotine with Ethyl cellulose/Whatman filter paper as rate controlling membrane were formulated. Prepared patches were evaluated for thickness, drug content, content uniformity, weight variation, water uptake, stability and in vitro release characteristics using sigma membrane, excised rat skin and excised rabbit skin as membranes mimicking the human skin. All the prepared patches were flexible, fairly uniform in drug content and released nicotine with non-fickian diffusion involving erosion of the polymer matrix over a period of 24 hours. EC and Whatman filter paper, used as rate controlling membranes, though did not have a direct effect on release rate of drug significantly from patches, demonstrated advantage of minimizing irritation to the site of application due to direct contact of nicotine. In vivo drug release studies were conducted in Wistar albino rats. Patches were applied on the dorsal portion of the animal and at regular intervals of time, patches were removed and analysed for drug content. Results indicated that there exists a fair correlation between in vitro and in vivo studies.