A facile approach to fabrication and characterization of novel herbal microemulsion-based UV shielding cream

Abstract

Abstract Background Since many decades, phytoconstituents are well known for their potential therapeutic benefits but the development of herbal products has been limited due to difficulties like collection, isolation, stability and aqueous solubility of the phytoconstituents. The present study focuses on the development of microemulsion-based sunscreen cream formulation containing therapeutically active phytoconstituents like lycopene, β-carotene and curcumin which are reported for both antioxidant and ultraviolet radiation barrier properties. But the major hurdle in the development of the formulation is poor solubility and stability of these 3 components. Microemulsion preparation helps to enhance the solubility and stability of the final product. Screening of oils, surfactants and cosurfactants were done based on solubility studies followed by the construction of pseudo-ternary phase diagrams, sesame oil, span 80 to tween 80 (surfactant) and isopropyl alcohol (co-surfactant) which were selected to stable microemulsion. Result Based on a solubility study of components and pseudo-ternary phase diagrams, surfactant to co-surfactant (Smix) with 2:1 ratio and oil to Smix with 2:8 ratio were selected for preparation of the final microemulsion. Results show an average globule size of 208 nm, conductance 0.935 moh/cm, pH 7.1, zeta potential − 17.5 mV, refractive index 1.002, polydispersibility index 0.342, percent transmittance 90.68% and viscosity 82.45 cps. In a drug content study, the presence of lycopene, β-carotene and curcumin was found to be 87.53, 85.08 and 90.65%, respectively. Finally, microemulsion-based sunscreen cream was prepared and evaluated for various parameters like pH, extrudability, spreadability and drug content study. The sun protection factor (SPF) of microemulsion and cream was found to be 36.32 and 37.65, respectively. The stability study data shows better stability of the final formulation. Conclusion Formulation of microemulsion-based sunscreen cream may be a better option in the design and development of herbal phytoconstituents.