Development of a hydrogel containing bisabolol-loaded nanocapsules for the treatment of atopic dermatitis in a Balb/c mice model

α-Bisabolol (αBIS), a plant-derived compound with anti-inflammatory properties, is potentially a therapeutic agent for Atopic dermatitis. However, its poor water solubility and photoinstability limit its topical application. Therefore, the present study, aimed to develop cationic polymeric nanocapsules of αBIS to improve its skin delivery, photostability, and therapeutic efficacy. The αBIS-loaded nanocapsules were prepared using the solvent displacement technique. A Box-Behnken (BB) design was employed to statistically optimize formulation variables and αBIS-loaded nanocapsules characterized by particle size, surface charge and encapsulation efficiency. The optimal formulation was selected, and the spherical shape of the nanocapsules was confirmed by scanning electron microscopy (SEM). Furthermore, hydrogel containing αBIS-loaded nanocapsules was prepared by thickening of nanocapsule suspension with Carbopol 934 and evaluated for rheology, in vitro drug release and skin permeation. Furthermore, a mice model of atopic dermatitis was used to evaluate the anti-inflammatory potential of the hydrogels. The optimal formulation displayed a spherical morphology under scanning electron microscopy (SEM) with an optimum particle size of 133.00 nm, polydispersity index (PDI) of 0.12, high EE% of 93 %, and improved optical stability of αBIS in the prepared nanocapsules compared to the free drug. The nano-based hydrogels demonstrated non-Newtonian pseudoplastic behavior and an increased αBIS in vitro release profile without causing skin irritation in rabbits. Drug retention within the dermis and epidermis layers significantly surpassed that of drug-free hydrogel. Moreover, in vivo histopathological studies and myeloperoxidase (MPO) enzyme activity, revealed that hydrogel containing bisabolol nanocapsules exhibited The best anti-inflammatory effect. The results showed that hydrogels containing bisabolol nanocapsules markedly alleviated dermatitis-related inflammation and reduced skin thickness in Balb/c mice. Our findings support nanocapsules as an effective drug delivery system to enhance αBIS stability, bioavailability, and therapeutic efficacy in AD treatment.

Preparation and characterisation of self-emulsifying drug delivery system (SEDDS) for enhancing oral bioavailability of metformin hydrochloride using hydrophobic ion pairing complexation

AIM

The aim of this study was preparation of a self-emulsifying drug delivery system (SEEDS) containing metformin hydrochloride.

METHODS

Hydrophobic ion paired complexes were prepared by electrostatic interaction between metformin and sodium lauryl sulphate (SLS). The nanodroplets were optimised using two-level full factorial methodology and their morphology were examined. In vitro release of metformin from SEDDS was evaluated in simulated gastric and intestinal fluids. Finally, the ex-vivo efficacy of the optimised formulation in enhancing the intestinal permeability of metformin was evaluated using non-everted intestinal sac.

RESULTS

The data revealed that in weight ratio 1:4(metformin: SLS), the highest recovery was achieved. The physico-chemical properties of the optimised nano-droplets including size, polydispersity index (PdI), zeta potential, and loading efficiency (%) were 192.33 ± 9.9 nm, 0.275 ± 0.051; -1.52 mV, and 93.75 ± 0.77% (w/w), respectively.

CONCLUSIONS

The data obtained from the intestinal transport study demonstrated that SEDDS can significantly enhance the oral permeability of the compound.