FORMULATION AND EVALUATION OF AN ANTI POLLUTIONNIOSOMAL FILM-FORMING SPRAY FOR URBAN-AGING DEFENSE USING ECTOINE AND L-ASCORBIC ACID (VITAMIN C)

AbstractThe present study aimed to develop, optimize, and characterize an Ectoine-loaded niosomalfilm-forming spray for prolonged topical protection against urban pollution-induced oxidativeskin aging. Ten formulations (F1–F10) were prepared using the thin-film hydration methodby varying Span 60 (100–200 mg) and cholesterol (50–75 mg), while maintaining constantconcentrations of Ectoine, Vitamin C, Eudragit RS100, and PVP K-90. Preformulationstudies confirmed the high aqueous solubility of Ectoine. UV-visible spectrophotometricanalysis in phosphate-buffered saline (pH 7.4) showed a λmax of 215 nm, with a linearcalibration range of 5–40 μg/mL (R² = 0.9984). Among the developed formulations, F10containing 175 mg Span 60 and 60 mg cholesterol exhibited the most desirablecharacteristics. The optimized formulation demonstrated a mean particle size of 182.5 nmwith a PDI of 0.185, indicating a narrow and uniform nanoscale distribution. TEM and SEManalysis confirmed smooth, spherical vesicles with intact bilayer structures and minimalaggregation. F10 exhibited a zeta potential of -34.8 ± 1.1 mV and maximum entrapmentefficiency of 81.62 ± 0.54%. In vitro drug release studies in PBS (pH 7.4) demonstratedsustained release, with 59.26 ± 0.82% release at 12 h and 82.48 ± 0.96% at 24 h. After 30days of storage at 25°C, the formulation maintained physical stability and 92.1% drugcontent. Overall, F10 demonstrated promising nanoscale characteristics, sustained release,and stability, indicating its potential as a novel film-forming topical system for prolongedurban anti-pollution and anti-aging skin defense.