Formulation, Development and Evaluation of Topical Microemulsion Based Spray of Roflumilast

The objective of present research work was to formulate microemulsion spray of Roflumilast for the treatment of psoriasis. Roflumilast microemulsion spray was prepared and optimized, by using simplex lattice design. Spectrometric analysis of Roflumilast was done by using UV- Visible spectrophotometer and DrugExcipients compatibility study was conducted by Fourier transform infrared spectroscopy. Oil, surfactant, and co-surfactant were selected based on the results of a solubility study for the formulation of microemulsion, while the ratio of surfactant to co-surfactant (Smix) was determined through pseudo-ternary phase diagram study. Roflumilast microemulsions spray were prepared by phase titration method. Simplex Lattice Design was applied using Design Expert 22.0.3.0 software. Concentration of Oil (X1) and Concentration of Smix (X2) and Concentration of Water (X3) were chosen as independent variables, while % Transmittance (Y1), Globule Size (Y2) and % Drug Diffusion (Y3) were selected as dependent variables. All seven microemulsion spray were evaluated further for different parameters such as pH, Viscosity test, centrifugation study, Polydispersity Index, spray pattern, Drug content and %drug diffusion. Check point batch was prepared and evaluated for the validation of model. Optimized microemulsion was evaluated for Globule size, Polydispersity index (PDI) and zeta potential. Optimized microemulsion was transferred into a spray Bottle and evaluated for different parameters such as color, homogeneity, consistency, pH, viscosity, % drug release and % drug content. Microemulsion spray was subjected to stability study under accelerated condition for one month.