Development of Quercetin-Loaded Bilosomes for the Management of Psoriasis

Background: Psoriasis is a chronic skin disorder characterized by persistent inflam-mation, keratinocyte hyperproliferation, and cytokine imbalance. Novel drug delivery methods include lipid-based carrier systems such as ethosomes, transferosomes, and bilosomes, which aid in the medication administration to the body. Quercetin is a plant flavonoid with strong antioxi-dant and anti-inflammatory properties, although it is classified as a BCS IV drug due to its limited permeability and solubility. Bilosomes are carrier systems composed of bile salts with particle sizes ranging from 5 to 250 nm. Objective: The present study aimed to develop a quercetin-loaded bilosomal gel and to evaluate its antipsoriatic activity in mice. Methods: In the present study, quercetin-loaded bilosomes were prepared using Span 60, choles-terol, sodium deoxycholate, and ethanol. The formed dispersion is converted into a gel formula-tion using a carbopol base for topical delivery in psoriasis treatment. The bilosomal dispersion is evaluated for particle size, zeta potential, Polydispersity index, and entrapment efficiency. In vitro and ex vivo studies are conducted using a Franz diffusion apparatus, and an imiquimod-induced psoriasis model is employed to assess the in vivo efficiency of quercetin bilosomal gel. Results: The particle size, Polydispersity index, and zeta potential of the optimized bilosomal batch were 250 nm, 0.2, and -25 mV, respectively. In the in vitro study, 60% of the drug release was observed from the quercetin bilosomal gel. Through the evaluation of Psoriasis Area and Severity Index (PASI) scores, histopathological studies, and spleen weight in imiquimod-induced mice, it was found that bilosomal quercetin gel exhibited better antipsoriatic activity compared to conventional quercetin gel. Conclusion: Bilosomes can serve as an effective carrier system for quercetin in the management of psoriasis.