FTIR characterization of a nanostructured carbon-based substrate coated with electropolymerized molecularly imprinted poly-o- phenylenediamine for arabinose determination

MIGUEL SALES PORTO DE SOUSA; C. A. FERRETTI; MARÍA N. KNEETEMAN; LEONARDO LATARO PAIM

Camboriú

Congreso; XVIII Brazilian MRS Meeting; 2019

Sociedad Brasilera de Química

Second-generation ethanol (2G-ethanol) is an alternative to reduce dependence on fossil fuels, since it is a renewable option and does not affect human food, as opposed to the production of first-rate ethanol generation. Thus, the development of methods for the analysis of compounds of interest, such as arabinose, from the hydrolysis of lignocellulosic biomass, is of great relevance for the search for greater efficiency in the process of obtaining 2G-ethanol. Therefore, the objective of the present work is to characterize, through Fourier-transform infrared spectroscopy(FTIR) and Differential pulse voltammetry (DPV), graphite/paraffin composite sensors modified with functionalized carbon nanotubes (FMWCNTs), based on molecularly imprinted polymers for the determination of arabinose. To prepare the electrochemical sensors, graphite and paraffin were used in the ratio 7:3(v/v), and then their surfaces were modified with FMWCNTs[1]. After modification with FMWCNTs, the electropolymerization of the MIPs[2] is performed through 20 consecutive sweeps in the range of -0.4 V to 1.0 V (50 mV s -1 ) in acetate buffer pH 5.1 containing 7.0 x 10 -4 mol L -1 of o-phenylenediamine and D-arabinose 3.0 x 10 -4 mol L -1 . Thus, a nonconductive film is formed wherein, upon removal of the template molecule, specific functional groups and cavities are left in the polymer matrix. By means of the FT-IR technique, a qualitative and semiquantitative analysis of the sensor was obtained, as well as the absence of characteristic bands of arabinose, indicating the successful removal of the model molecule. And through the DPV technique, the increase of the electron transfer after the modification with FMWCNTs, and the behavior of the MIP film isevidenced.