SUNSCREEN: DEVELOPMENT, PRELIMINARY STABILITY TESTS AND EVALUATION IN VITRO OF SUN PROTECTION FACTOR (SPF).

Abstract

Sunscreen use is the most common photoprotection alternative used by the population, and so these products should  offer improved protection with broad - spectrum, UVA and UVB protection. The aim of the present study was to
develop sunscreens emulsions and to evaluate their preliminary stability and in vitro photoprotective efficacy. Five formulations were prepared by phase inversion using differences concentrations of Non-ionic self-emulsifying base,
Non-ionic surfactant and viscosity agent. The in vitro Sun Protect Factor (SPF) was determined by spectofotometer method and the formulations were stored at 25 e 37°C by fifteen days. Preliminary stability tests was carried out in
triplicate with evaluation by macroscopic analysis, pH testing, centrifugation and viscosity assessment. The results demonstrated that two formulations (F4 and F5) were stable, but the formulation F4 presented high viscosity. In
summary, the formulation F5 (SPF 24.32±0.025) was stable and presented the most agreeable sensory properties.