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98 Asif Nawaz et alrabbit skin in such a way that the drug layer ofthe patch was facing to the epidermis of therabbit skin and was then fixed in between thedonor and receptor compartments of the FranzCell apparatus. The temperature of receptorsolvent was maintained at 37°C ± 1 °C withconstant circulation of hot water. Samples ofeach 2 mL were withdrawn from the receptorcompartments at specific time interval and wereimmediately replaced with fresh receptor solventalready maintained at the same temperature. Thesamples were filtered through a membrane filter[0.45µm]and were analyzed for the drugconcentrations by using UV-Visiblespectrophotometer at a detection wave length of262 nm [2].analyzer (Horiba LA300). The particle size andparticle size distribution is shown in the figure 2below. It could be seen from the figure that themaximum percentage i.e. 60 % was of theparticles having a diameter of 21.305 µm and theminimum concentration was of the particleshaving a diameter of 0.256 µm. The median ofthe Clotrimazole particles was 18.15 µm. Itcould be observed that the particle size ofClotrimazole was too small and was a goodcandidate for transdermal drug delivery systems.In vitro drug release kineticsKinetic model was applied to the in vitro releaseprofiles of Curcumin patches in order toinvestigate the way of drug release mechanism.The in vitro drug release mechanism ofCurcumin was determined by putting the in vitroreleasevalues in Korsmeyer Pappas kineticmodel.M t / M∞ = K 5 t nWhere M t / M∞ is fractional drug release fromformulation into the receptor solvent, K is drugdelivery constant and [n] is diffusion coefficient.The value of (n) in equation indicates the releasemechanism of particular drug in solvent. Thevalue of [n] if equal to 0.5 indicates quasi-Fickian diffusion mechanism, if (n>0.5) thenanomalous or non-Fickian diffusion mechanismexists and if its value is (=1) then Zero orderrelease mechanism exists.RESULTS AND DISCUSSIONPrior to Clotrimazole patch preparation, theparticle size and particle size determination ofClotrimazole was performed using Particle sizeFig. 2. Particle size and particle size distribution ofClotrimazole.Clotrimazole Patch evaluationClotrimazole transdermal matrix patches wereprepared by solvent evaporation technique.Different formulations of Clotrimazole patchwere prepared with/without penetration enhancerat different concentrations in order to optimizethe drug release patters. A combination of twopolymers (Ethocel and Eudragit) was used in thepatch formulations to extend the release patternsof Clotrimazole across synthetic membrane aswell as rabbit skin. The synthesized transdermalpatches of Clotrimazole were transparent,smooth, uniform and flexible. The values ofdifferent parameters applied to transdermalpatches could be seen in the table 4 below. Allthe values of different parameters suggest thatthe patches were suitable for topical application.Table 4. Results of physico-chemical parameters applied to Clotrimazole transdermal patch.ClotrimazoleClotrimazole Patch with olive oil at different concentrationsS. No. Parameters patch0.5% 1% 1.5% 2% 2.5% 3%(Blank)1 Thickness (mm) 0.18 ± 0.01 0.17 ± 0.01 0.18 ± 0.01 0.17 ± 0.01 0.18 ± 0.01 0.19 ± 0.01 0.18 ± 0.012 Weight ariation (mg) 0.361 ± 0.03 0.370 ± 0.07 0.363 ± 0.04 0.367 ± 0.05 0.369 ± 0.06 0.365 ± 0.05 0.366 ± 0.053 Tensile strength 12.98 ± 0.02 13.10 ± 0.02 13.07 ± 0.02 13.77 ± 0.01 13.54 ± 0.02 12.41 ± 0.01 13.98 ± 0.024 Folding endurance >140 >178 >148 >144 >150 >151 >1675 % Moisture loss 3.423 ± 0.033 3.591± 0.021 3.837 ± 0.052 3.697 ± 0.043 3.611 ± 0.049 3.430 ± 0.021 3.587 ± 0.0376 % Drug content 99.1 98.5 98.8 99.2 98.7 98.2 98.4