CeVO₄-CNT-nafion modified glassy carbon electrode for voltammetric detection of 3-nitrotyrosine: a biomarker of protein nitration

Myofibrillar protein (MP) suspension was nitrated by exposing to nitrite. • 3-Nitrotyrosine (3-NT) is a biomarker of MP nitration. • A Sensor was made by CeVO 4 -CNT-Nafion nanocomposite modifying on GCE. • 3-NT in nitrosative MP was detected by the sensor coupled with CV. • The proposed method was compared with HPLC method. 3-Nitrotyrosine (3-NT) is a recognized biomarker of protein nitration. In this study, an electrochemical nonenzymatic sensor was developed for 3-NT detection by modifying a glassy carbon electrode with a nanocomposite of CeVO 4 , carboxylated carbon nanotubes (CNT), and Nafion. Scanning electron microscopy revealed that flower-like CeVO 4 nanoparticles were uniformly embedded within the interconnected tubular network of CNT and Nafion. Under optimal conditions, the sensor exhibited a wide linear response to 3-NT in the range of 10 to 900 μM, with a detection limit of 1.20 μM. To validate its practical application, myofibrillar protein (MP) was extracted from pork and exposed to varying concentrations of nitrite at pH 6.0, leading to the formation of 3-NT. These nitrosative MP samples were then analyzed using the developed sensor, and the results were compared with those obtained by HPLC using split samples. The findings demonstrated no significant differences between the two methods. Download: Download high-res image (105KB) Download: Download full-size image