Design and Development of a Topical Emulogel Formulation Containing Tenofovir Disoproxil by Factorial Design

Background: Tenofovir disoproxil is a drug used to treat chronic hepatitis as well as HIV/AIDS prevention for skin or mucus membrane. Aim: The 2 ³ factorial design was chosen because it necessitates the application of design, which exhibited 13 experimental runs constructed using design expert software. Materials and Methods: The independent variables include methocel k100 LV (X1), Koliphor p188 (X2), and Tween 80 (X3), with an experimental design. Using FTIR and DSC, the prepared emulgels were evaluated for their physical appearance, spreadability, pH, washability, in-vitro dissolution studies, ex-vivo diffusion studies, in-vitro intestinal permeability studies, polydispersity index, particle size, and zeta potential, drug release kinetics, and drug-excipient compatibility studies . Results and Conclusion: The product is easy to spread and wash, and no skin sensitivity has been noted. The order of drug dissolution in various formulations is illustrated below: E5<E7<E6<E10<E1=E3=E4=E8=E11=E12=E13<E9<E2. The formulation R ² was greater when fitted to the first order equation, indicating that the formulations had a first order release in E2, E9, and E10. The high R ² with Higuchi is exhibited in E1, E3, E4, E5, E6, E7, E8, E11, E12, and E13. The release exponent ('n' value) formulation E5 demonstrates fickian diffusion, while E1, E3, E8, E11, E12, and E13 demonstrate a non-fickian diffusion mechanism. E2, E4, E6, E7, E9, and E10 illustrate super case II transport. The E5 formulation follows Higuchi diffusion, and diffusion exponents less than 0.5 suggest Fickian diffusion. Ex vivo diffusion tests were performed to optimise formulation E5 using sheep skin, resulting in 100% drug release within 6.0 hours of diffusion. The drug release has zero order kinetics (r ² =0.8741) and fickian diffusion (n=0.2597). In vitro intestinal permeability studies were conducted to optimise formulation E5 utilising sheep intestine (T100) for 100% drug release in 5.0 hours. The medication is released through Higuchi diffusion (r ² =0.8831) and non-fickian diffusion (n=0.6923). The FTIR and DSC investigations revealed no interactions between tenofovir and the various excipients used. The particle size of the emulgel formulation (E5) was found to be 244.3nm, with a polydispersity index of 0.113. This revealed a relatively homogeneous dispersion, with formulation E5 having a zeta potential of -43.1mv. The ANOVA of the time required for 100% drug release (T100) was statistically significant (p<0.0078).