The study was designed to investigate the optimation of preparation of transdermal patch sodium diclofenac matrix type. ln this study, matrix-type base containing diclofenac sodium were prepared using polymeric combination of EC N-20 and PVP K-30 in different ratios (9:1 (Formula l): 8:2 (Formula ll); 7:3 (Formula lll)) and 6:4 (Formula lV). The moisture content was calculated as a difference between initial and final weight with respect to final weight. The homogeneity of patch surface was determined using Scanning Electron Microscope (SEM) Released test using dissolution tester were carried out in 500 mL of phosphate buffer salin pH7.4 t 0.05 at temperature 37 t 0.5"C with speed of swirl 50 rpm. The concentration of sodium diclofenac released was determined using spectrophotometric method at )', 276 nm. Data was analyzed by statistic programmed of SPSS using one way0.05). lt is concluded that the polymeric analysis of variance with degree of believed 95% (o =combination EC N-20 and PVP K-30 in composition 7:3 (Formula lll) was the best formulation
