Cellulose microsponges based gel of naringenin for atopic dermatitis: Design, optimization, in vitro and in vivo investigation.

Naringenin, a bioflavonoid, is a natural alternative for atopic dermatitis that possesses anti-inflammatory, antioxidant and photo-protective action. The primary objective of this study is to prepare and evaluate naringenin-loaded microsponge gel for dermatitis. Ethyl cellulose based microsponges of naringenin were prepared by quasi-emulsion-solvent diffusion and statistically optimized by 3 factorial design. After in vitro characterization, optimized microsponge batch (Trial 3) was incorporated into Carbopol base to prepare 1% naringenin-loaded microsponge gel (NGMSG1%) which was evaluated for skin irritation, in vivo efficacy and drug deposition in DNFB-challenged albino Wistar rats in comparison to 1% plain naringenin gel (NGG1%). The average particle size and in vitro drug release of optimized microsponge formulation was observed to be 180 μm and 92.3% ± 2.37 at the end of 24 h, and entrapment was achieved till 82%. SEM study confirmed porous, spherical shaped microsponges whereas FTIR and DSC data supported the formation of microsponges. No skin irritation was observed with NGMSG and NGG in animals. NGMSG1% showed faster healing, substantial reduction in thickness of swollen earflap and WBC count than NGG1%. Similarly, NGMSG showed 3-fold greater drug deposition in skin than plain gel. Thus, naringenin loaded microsponge gel can be further explored as natural remedy for atopic dermatitis.