determination of gallic acid by multilayer titanium metal organic framework/multi-walled carbon nanotubes modified electrode

Abstract: gallic acid (ga) is an omnipresent compound found in green tea, fruits and vegetables. ga possesses properties such as antioxidant [1], anti-viral, antibacterial, anti-diabetic, anti-cancer, anti-aging, and anti-inflammatory properties [2]. ga shows cytotoxic effects against cancer cells without harming normal cells [3]. recently, in order to increase the catalytic performance, nanocomposites including mofs and mwcnts have been developed [4]. in this work, we have successfully developed a sensor for the detection of ga based on electrodeposition of multilayer films of titanium based metal organic framework and multi-walled carbon nanotubes (ti-mof/mwcnts). scanning electron microscopy and energy dispersion spectroscopy were used to investigate the surface of the modified electrode. the electrochemical characterization experiments showed that the ti-mof/mwcnts modified glassy carbon electrode had excellent electronic conductivity and high stability. several parameters such as ph, concentration of modifiers, scan rate and the amount of nanocomposite controlling the performance of the sensor were examined and optimized. differential pulse voltammetry experiments indicated a linear concentration range of ga from 1.0 × 10-7 m to 1.0 × 10-3 m, the detection limit was estimated to be 3.5 × 10-7 m. the repeatability, reproducibility and stability of the developed sensor were examined and the results showed that the developed sensor was in superior in condition (rsd=1.71%). the proposed electrochemical sensor exhibited high specific electrochemical response to ga and it was used for voltammetric determination of ga in real samples of green tea and black tea.