Asma Aslam¹, Rummana Riaz¹, Yasser Shahzad², Atif Akber³, Ikram Ullah Khan^4,, Syed Nisar Hussain Shah⁵

In this study, synergistic effect of penetration enhancers, namely propylene glycol (PG) and sodium lauryl Sulphate (SLS) on transdermal absorption of 2-Methyl-2-phenoxy-propionic acid (MPA) was evaluated with aid of response surface methodology (RSM) based formulations. The prepared formulations were characterised and subsequently subjected to diffusion cell experiments through a well-established skin mimic, namely silicone membrane. Data obtained were statistically analysed using analysis of variance (ANOVA) and regression analysis. Comparisons were made with the control and among different parameters of formulations. PG (X1) and SLS (X2) were selected as independent variables, whereas the cumulative amount of MPA were used to calculate dependent permeation kinetic parameters like lag time (t_lag) and enhancement ratios (ER). It was observed from the results that PG had a significant effect on MPA absorption from the lotion followed by SLS and their combination showed a significant enhancement (p< 0.05) in the flux from the formulated lotions compared to the control. The highest enhancement ratio (ER=8.6) was observed for L4. Contour plots were then drawn to depict the relationship between independent and response variables. Among the formulations, L4 showed highest flux value with less lag time (12.2 min), thereby, identified and selected as an optimized formulation. In conclusion, the combination of PG and SLS can be successfully utilized as permeation enhancers for transdermal drug delivery of MPA with minimal side effects.

propylene glycol, sodium lauryl sulphate, permeation, response surface methodology, lotion