Determinação de rutina sobre nanotubos de carbono modificados com ciclodextrina

Abstract

Flavonoids have gotten the interest of many research laboratories in virtue of the many health benefits these compounds provide, such as: antioxidant, anti-cancer, anti-aging properties and contribution to the formulation of drugs. Due to the environmental, biochemical, chemical and pharmacological importance, the accurate determination of flavonoids has gained significant attention in the scientific community. This work presents the development of an electrochemical platform based on multi-walled carbon nanotubes (NTCPM) modified with hydroxpropyl-y-cyclodextrin (y-CD) for the determination of rutin in nanomolar concentration levels in pharmacological and in regional plants extracts. To do so, the surface modification of NTCPM with y-CD was evaluated with Fourier-transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). Electrochemical measurements were performed using the NTCPM- (y-CD) system and different voltammetric techniques, which allowed to define the square wave voltammetry (VOQ) as the most appropriate and to establish, under optimized experimental conditions, the linear range between 39,22 and 975,00 nmol L-1 for the detection of rutin in aqueous solutions. Limits of detection (LOD), quantification (LOQ) and sensitivity of 24.39 nmol L -1 , 0.032 µA L nmol-1 and 7.32 nmol L -1 were found, respectively. The selectivity for possible interferents, including two flavonoids, was tested with recovery rates of pharmacological and in extracts plants samples close to 100%, besides HPLC validation.