Chitosan/Starch-based Hydrogels as Drug Delivery Carrier for Controlled Release of Hydroxychloroquine

Abstract

Chitosan/starch cross-linked microspheres were prepared as drug delivery system for controlled release of hydroxychloroquine, the systemic lupus erythematosus drug. Moreover, sodium hexametaphosphate (SHMP) as a physical cross-linker and glutaraldehyde (Glu) as a chemical cross-linker have been used. The size and shape factor(S) of the prepared microspheres was studied using scanning electron microscope technique. The Glu microspheres shows size of their spherical particles (82.5μm) and shape factor (S=0.862) as a high values in comparison with SHMP microspheres with size (39.7μm) and shape factor (S=0.811) means both Glu and SHMP microspheres are rough but Glu microspheres are more roughness. The swelling studies shows Glu microspheres have a higher degree of swelling (DS=130%) in pH= 9 media while SHMP microspheres the more compact microspheres shows higher (DS=160%) in acidic pH= 2 media. The microspheres were loaded with hydroxychloroquine and then sustained the drug in controlled, and because of high electrostatic interactions between drug and system ions, the SHMP microsphere were loaded with higher maximum loading percentage (Lmax=55.8% (w/w)) comparing with Glu microspheres of (Lmax=46.5% (w/w)). Both systems Glu and SHMP microspheres shows controlled drug release behaviors. The Glu microspheres shows (40.0 mg) and (40.5 mg) controlled release in pH = 7.4 and PH= 9.4 media respectively, out of (46.5 mg) maximum loading percentage, while only (30.0 mg) controlled release in pH = 1.3 and only for 18h controlled release time, while 30h and 36h controlled release time in pH= 7.4 and pH= 9.4 respectively. The SHMP microspheres shows controlled drug delivery with more sequence almost in all tested pH of the release media, where they release (45.0 mg), (45.0 mg), and (47.0 mg) under controlled release in pH=1.3, pH= 7.4, and pH=9.4 respectively, out of (55.8 mg) maximum loading percentage and with 30h, 36h and 36h controlled release time, respectively. The prepared microspheres were characterized using FTIR, 1H NMR, (TGA, DTA, and DSC), XRD and FESEM analysis. The prepared systems were found suitable as controlled drug systems for delivery of hydroxychloroquine drug.