Acitretin and aloe-emodin loaded chitin nanogel for the treatment of psoriasis

The present study focuses on the development of an effective topical nanogel formulation of two antipsoriatic drugs; Acitretin (Act) and Aloe-emodin (AE) using natural polymer chitin. Simple regeneration chemistry was used to prepare Chitin Nanogel Systems (CNGs). The developed control chitin (CNGs) nanogels, acitretin loaded chitin nanogels (ActCNGs) and aloe-emodin loaded chitin nanogels (AECNGs) were characterized by DLS, SEM, FTIR, XRD and TG-DTA. The systems were found to be spherical in shape with a size range of 98 +/- 10, 138 +/- 8 and 238 +/- 6 nm having zeta potential values of +28 +/- 3, +27 +/- 3 and +25 +/- 6 mV for CNGs, ActCNGs and AECNGs respectively. The in vitro haemolysis assay revealed that all the nanogel systems are blood compatible. The systems exhibited higher swelling and release at acidic pH. The ex vivo skin permeation studies using porcine skin confirmed the higher deposition of the systems at epidermal and dermal layers, which was confirmed further by fluorescent imaging. The in vivo anti-psoriatic activity study using Perry's mouse tail model and skin safety studies confirmed the potential benefit of the system for topical delivery of acitretin and aloe-emodin in psoriasis. (C) 2016 Elsevier B.V. All rights reserved.