Deproteinized Natural Rubber Latex as Matrix Base of Meloxicam Transdermal Patches

Abstract

This study aims to formulate and evaluate the meloxicam (MX) transdermal patches using deproteinized natural rubber latex (DNRL) as a polymer matrix due to its good film forming characteristics. Hydrophobic drug, MX was firstly dissolved in hydroalcoholic solution and incorporated into DNRL with various concentrations of the drug (1-5%w/w). These mixtures were then cast on the glass plate prior to drying and thereafter obtaining the MX-loaded transdermal patches. Increasing amounts of the drug provided more opaque films with more precipitation of drug in films. The highest amount of MX was 3%w/w to incorporate with DNRL to obtain the acceptable patch without any visible precipitation. Compatibility of each ingredient in the formulation was confirmed using differential scanning calorimeter and X-ray diffractometer. The in vitro drug release study showed the increment of MX release from 7.88±0.43% to 13.33±0.87% in receptor medium of modified Franz diffusion cell when the drug concentration in the patches was increased from 1 to 3%w/w. The in vitro drug permeation study also found that MX could penetrate from DNRL transdermal patch through the porcine skin. However, these release and permeation amounts of MX were rather low that should be improved with some specific techniques and should be further investigated.