ABSTRACT
Chitosan has become promising as a biomaterial because of its biocompatible, biodegradable nature and non-toxic. The biochemical and antioxidant properties of chitosan modified with acetylacetone and ethylenediamine (Cacen) or diethylenetriamine (Cacdien) associated with ceftazidime (F) were investigated. Chitosan was characterized using Elemental Analysis (CHN), Thermal Analysis (TG/DTG/DSC), X-Ray Diffractometry (XRD), and was investigated an in vitro hemolytic cytotoxicity test, Artemia saline larvae for toxicity and in vitro antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl). The chemical modification was confirmed by CHN, XRD and TG. The Cacen, Cacdien, CacenF and CacdienF derivatives presented high percentages of nitrogen (7.6%, 7.9%, 14.1% and 19.2%, respectively), confirming the modification and drug adsorption. The average molecular weight of chitosan and its derivatives were 132â¯kDa, with very few variations after modification. This incorporation decreased in the crystallinity index of Cacen (7.1%) and Cacdien (4.3%), as well as the incorporation of the drug (CacenF 0.3% and CacdienF 3.4%). FTIR spectra showed bands at 1580-1654â¯cm-1 referring to carbonyl and imine group and bands at 3500-3300 and 1462-1264â¯cm-1 related to vibration and deformation the amine group. 13C NMR spectroscopy was observed new peaks in carbonyl and imine regions (170-200â¯ppm). The thermal stability of the derivatives without the drug improved according to TG/DTG/DSC analysis, however there were decreased in the derivatives with the drug. The biocompatibility of the derivatives was confirmed by the low hemolytic rate (<5%), non-toxic on Artemia salina (LD50%>3000â¯ppm), and significant index (1-34%) of antioxidant activity. The results demonstrated that chitosan and its derivatives are promising biomaterials.
