Síntese de materiais híbridos de ouro/PEDOT-PLLA e aplicações em detecção eletroquímica

Novel materials containing noble metal nanoparticles and conducting organic polymers are being synthesized and studied as electrode materials in many fields of research. Gold nanoparticles have been applied to tune conducting polymers like PEDOT due to gold physical and chemical properties, like very high electric conductivity [1, 2]. In this work hybrid materials of Au nanoparticles and the polymer PEDOT-PLLA were synthesized and studied. PEDOT-PLLA is a polymer derived from poly (3, 4-ethylenedioxythiophene) that contains lateral chains of poli(L-lactic acid) attached to the oxyethylene rings. PEDOT-PLLA presents biodegradable properties, making it very interesting as electrode material. The hybrids were synthesized in a 2-step procedure in solution. (1): HAuIIICl4 reacts with EDOT-PLLA to form Au nanoparticles, and (2): the product reacts with K2S2O8 to promote the oxidative polymerization of EDOT-PLLA. he hybrids were studied through electron microscopy, andgold nanoparticles are visible as dots in the polymermatrix (Figure 1). Their sizes are up to 20 nm. The hybrid material was immobilized onto glassy carbon (GC) electrodes by casting and vacuum drying. The immobilization techniques were optimized and the modified electrodes were electrochemically studied. Cyclic voltammetries were performed varying [H2O2(aq)] and H2O2(aq) was detected amperometrically with this electrode.