Nanostructured Sensors for Determination of 3-(3,4-Dichlorophenyl)-1,1-Dimethylurea Based in Molecularly Imprinted Polymers (MIPs) Deposited in Screen Printed Carbon Nanotubes

A selectivity sensor based on molecularly imprinted polymers (MIP) was developed for determination of 3-(3,4-Dichlorophenyl)-1,1-dimethylurea (diuron) in environmental samples. The molecularly imprinted polymers (MIP) were synthesized using non-covalent interactions and they were selected based on computer modeling. For the construction of the sensor, screen-printed carbon nanotubes electrodes were modified with Nafion® and MIP/NIP (not imprinted polymer). We used cyclic voltammetry to monitor the electrochemical response and Square Voltammetry Wave, Chronoamperometry and Differential Pulse Voltammetry to quantification of diuron in a range of response 0 - 1.1 V in a phosphate buffer solution (pH=8). All parameters affecting the sensor were optimized. The system showed a linear response at concentrations of 0.1 ppm to 15.0 ppm in phosphate buffer solution 0.1 mol L^-1 (pH=8) and the detection limit of 0.05 ppm. The sensor was applied in water samples obtained promising results.