Photoelectroanalytical Sensor Based on TiO2 Nanoparticles/Copper Tetrasulfonated Phthalocyanine for Detection of Dopamine Exploiting Light Emitting Diode Irradiation

In this manuscript, a novel photoelectroanalytical sensor for detection of dopamine based on anatase TiO2 nanoparticles sensitized with copper tetrasulfonated phthalocyanine (CuTsPc/TiO2) was developed. The CuTsPc/TiO2 photoelectroanalytical sensor shows high anodic photocurrent under visible light emitting diode irradiation in comparison to pure anatase TiO2 nanoparticles. The CuTsPc/TiO2 composite shows a photocurrent about 2.5-fold higher than those of pure TiO2 nanoparticles or CuTsPc modified electrode. The CuTsPc/TiO2 composite shows a low charge transfer resistance in comparison to its individual components as well as the impedance circle radius decreases significantly under UV light illumination. Under optimized conditions, the photoelectroanalytical sensor shows a linear response range from 4 up to 810 mu mol L-1 with a sensitivity of 3.0 nAL mu mol(-1) and limit of detection of 0.5 mu mol L-1 for the detection of dopamine. The photoelectrochemical sensor shows high photocurrent to dopamine in comparison to foreign species such as ascorbic acid, uric acid, glucose, K+, Na+, and Cl-.