Preparation of polyaniline submicro/nanostructures using l-glutamic acid: Loading and releasing studies of amoxicillin

Hybrid submicro/nanostructures of polyaniline (PANI) and l-glutamic acid (GA) were chemically prepared with the addition of ammonium persulfate (APS) as the oxidant. Different GA and APS concentrations were investigated in order to obtain the optimal conditions for the formation of high aspect ratio structures. TEM, electrical and XPS characterizations revealed that at monomer:amino acid:oxidant molar ratio of 1:0.25:1, the PANI presented a fibrillar morphology with diameters in submicro and nanometric scale, the structures were coating with the GA and the GA doped the PANI backbone. The fibrillar structures of GA coated-PANI efficiently adsorbed therapeutic doses of amoxicillin and controlled release of the drug can be achieved in function of pH environment, with a maximum cumulative release of 98% at pH 9 within 48 h.