LAUSR

Abstract The study's purpose intended to develop and optimize an NLC formulation for topical berberine administration with increased skin acne efficacy. The “three-parameters, three-level Box-Behnken design” was employed to improve the formulation based on vesicle size, PDI, and encapsulation efficiency. In-vitro profile for drug release, skin penetration investigation using confocal microscopy, skin irritation, anti-inflammatory, and anti-acne studies were performed on the optimized formulation. The vesicles with a size of 132.5 ± 10.34 nm, PDI of 0.224 ± 5.12, and entrapment efficiency of 85.956 ± 5.78% were found in the optimized formulation. The optimized formulation had spherical vesicles, according to TEM imaging. In vitro release studies showed that final optimized NLC formulation has cumulative release of drug (72.675 ± 3.686%), which was significantly greater as compared to NLC gel formulation (48.354 ± 4.893%). Thermo-analytical studies of NLCs formulation determined smooth drug interaction via rat skin membrane. Confocal microscopy revealed that, rhodamine-NLC formulation was traceable up to 54.9 μm across skin of rats, while solution of rhodamine penetrated only up to 20.4 μm of rat skin. Skin irritation study further showed significantly lower irritation level of skin (erythema: 0.50.231 and edema: 0.50.320) by applying optimized NLC-gel formulation compared to the control irritant. Furthermore, in comparison to the positive control, the anti-acne study demonstrated a decrease in all acne parameters, in addition to higher effectiveness over the commercially available formulation. These findings suggest that developed berberine loaded NLC gel could be a promising vehicle for the safe and effective topical administration of drugs to treat acne vulgaris.