SAMBILOTO LEAF NANOEMULSION AS A PHOTOPROTECTIVE AGENT: OPTIMIZATION OF TWEEN 20 AND PEG-400 CONCENTRATION USING THE REGULAR TWO-LEVEL FACTORIAL DESIGN

Objective: This study aims to determine the optimum concentration of Tween 20 and Polyethylene Glycol 400 (PEG-400) in Sambiloto leaf extract nanoemulsion. Methods: The formula of sambiloto leaf nanoemulsion was developed using the regular two-level factorial design based on responses of pH values, density, viscosity, and transmittance percentage. The optimum formula was tested for stability and photoprotective activity by determining the Sun Protection Factor (SPF) value and antioxidant activity. Results: Sambiloto leaf extract contains andrographolide at 3.397%. The optimum formula for nanoemulsion preparations was obtained at 10% of tween 20 and 10% of PEG-400. The optimum nanoemulsion had a distinctive green extract aroma, a transmittance percentage of 86.7±0.170, a globule size of 130.43±54.056 nm, a polydispersity index of 0.318±0.043, and a zeta potential of-26.5±0.544 mV. The optimum formula's photoprotective activity resulted in an SPF value of 42.944±0.026 and an IC50 of 103.611±1.085 ppm. There was no significant change in pH or transmittance percentage based on the stability test (p<0.05). Conclusion: The results show that the optimum formula of sambiloto leaf nanoemulsion could be a photoprotective agent that is also stable.