Hidróxidos Duplos Lamelares (HDLs) como carreadores de antimônio visando uma alternativa na quimioterapia da leishmaniose

Abstract

Leishmaniasis is a global relevance anthropozoonosis, classified as category I on Brazilian Tropical Diseases Program, concerning emerging and out of control diseases, and in a national context (especially regional), with reporting in the period from 2010 to 2012, of 52,862 new cases. The WHO recommends as main control measure to all diseases forms the use of chemotherapy, among these, the first choice drugs are antimonials. Although its use for almost 100 years, they have a number of limitations, including the uncomfortable parenteral administration route. This study proposes a research of Layered Double Hydroxides (LDHs) as bidimensional host matrix to antimonials drugs to research on Leishimaniasis chemotherapy, in order to use the oral therapy. The choice for LDHs is justified by its low cost, easy to synthesize in laboratory, significant ion exchange and biocompatibility. Thus, along this study, there were several lots synthesis of HDL precursor and characterized by means and some techniques. Biological assays were performed with the HDL precursor, where endocytosis and cytotoxicity in peritoneal macrophages were evaluated. Subsequently the preparation of binary systems via ion exchange was performed, where the variables concentration (1:2 and 2:1) antimony parent drug (tartrate of antimony and potassium III) and reaction time (2, 24, 48, 72 and 96 hours) were studied, and finally coating these nanossitemas. Through the characterization techniques the synthesis and robustness of the methodology of preparation of HDLs were confirmed. The formation of binary systems in powder form was confirmed with the aid of the techniques used for characterizing, as well as identifying the formation of antimony oxide with octahedral symmetry. The coating polymer was produced and also evaluated by TEM. Besides the low cost and easily laboratorial synthesis of the clay, the systems produced are promising, based on the choice of LDH as a nanocarrier of Sb3+, designated as responsible for antileishmanial action in the antimonials drugs. Furthermore, it does not induce citotoxicity and, analogously to current antimony-carbohydrates drugs, LDH would play the role of carbohydrates while undergoing endocytosis by macrophages (site of infection).