The enhancement of transdermal permeability of water soluble drug by niosome-emulgel combination

Na-alginate and Na-carboxymethyl cellulose (Na-CMC) are currently used to prepare gels and emulgels of transdermal anti-inflammatory drugs. Moreover, niosome has been shown to improve the transdermal permeability of water soluble drugs. The purpose of this study was to formulate a drug delivery system composed of combinations of gels or emulgels with niosomes encapsulating water soluble drug (Ketorolac Tromethamine (KT) as model drug). Proniosomal gels of the drug were prepared using Span 60 (Sp 60) and cholesterol in different ratios. Hydration of proniosomal gels with phosphate buffer (pH 5.5) gave niosomes entrapping KT at different percentages according to Sp 60/cholesterol ratio, drug concentration and total lipid concentration. To evaluate KT transdermal permeability from test formulae, the release of KT through cellophane membrane and rabbit skin were studied. Finally, the anti-inflammatory effects of KT in various test formulae were evaluated using a rat hind paw edema experiment. Results showed higher percentages of drug release through the cellophane membrane from Na-alginate systems than Na-CMC. The permeability studies revealed a high KT percentage passed through the rabbit skin from niosomal gels and niosomal emulgels. Conversely, alginate gel, emulgel and proniosomal gels gave lower fluxes of KT across rabbit skin when compared to niosomal combinations. The anti-inflammatory effects and permeability studies were increased in the following order: Na-alginate gel < niosomal gel < emulgel < niosomal emulgel. In conclusion, this study indicates that the combination of niosome and emulgel systems may significantly enhance the anti-inflammatory effect of KT when used transdermally.