Transdermal patch

The present study was aimed at developing Simvastatin loaded transdermal patch to prevent drawbacks associated with oral delivery of Simvastatin. Simvastatin is a BCS class II drug having poor aqueous solubility and good permeability. A transdermal patch of simvastatin was developed using various polymers and their combination like Eudragit RL 100, HPMC K4M, PVP K30 & Ethyl Cellulose. Polymer combination HPMC K4M & PVP K30 exhibited good film forming properties. Propylene glycol, oleic acid and glycerol were used as plasticizers to improve film-forming properties. Among these, propylene glycol exhibited excellent result but penetration was found to be less. Thus, penetration enhancers such as oleic acid, DMSO, PEG 200 were used to enhance permeability, of which DMSO was found to be excellent. A 22 factorial design was implemented using design expert software. The formulation was optimized on basis of 2 parameters percent cumulative release and percent drug content.  3D surface graph was plotted for the design. Grid survey indicated P1 batch (which contains HPMC K4M & PVP K30 as a polymer, DMSO as penetration enhancer & PEG as a plasticizer) is the optimized batch as it showed good drug content and in-vitro drug release. The drug release kinetics of transdermal patch of simvastatin was best expressed by Higuchi model of drug release.

Drug delivery through skin would provide a useful alternative to oral drug delivery, which has numerous side effects. Transdermal drug delivery systems are becoming more popular in the field of modern pharmaceutics. The purpose of this research was to develop a matrix-type transdermal therapeutic system containing drug Atenolol with different ratios of hydrophilic and hydrophobic polymeric systems (HPMC, EC and PVP) by the solvent evaporation technique by using 30% w/w propylene glycol as plasticizer, tween 80 as permeation enhancer and 4%PVA as baking membrane. The physico chemical properties like λmax determination, solubility determination, permeability coefficient determination, partition coefficient determination and physic chemical compatibility determination were done. The physic chemical properties of drug found out were in accordance with IP standards and the physico chemical compatibility of the drug and the polymers studied by infrared spectroscopy suggested absence of any incompatibility. Formulated transdermal films were physically evaluated with regard to thickness, weight variation, drug content, flatness, folding endurance, percentage of moisture content and water vapour transmission rate. Most of the formulations indicated good physical stability. In-vitro permeation studies performed by Franz diffusion cells. From the studies HPMC and P       VP are selected for optimisation and further studies are carried with these polymers with different ratios.