Electrochemical sensing of palmitic acid in guava oil using a surface modified with reduced graphene oxide-decorated manganese nanoparticles and electropolymerized poly(L-serine) film

Palmitic acid (PA) is a fatty acid that has important properties including anti-inflammatory and antitumor activity and can be applied in various industrial sectors. In this work, the first electrochemical sensor based on a surface containing reduced graphene oxide and manganese nanoparticles and molecularly imprinted p-Ser for detection in guava oil is electro synthesized and characterized electrochemically, spectroscopically, and microscopically. Under optimized conditions, an analytical curve was constructed, obtaining two linear ranges 2.0×10−12 mol L−1 to 1.0×10−11 mol L−1 and 1.0×10−11 mol L−1 to 1.0×10−10 mol L−1. The limit of detection (LOD) and amperometric sensitivity (AS) were estimated to be 8.6 × 10−13 mol L−1 and 6.2 × 105 μA L mol L−1, respectively. Interference assays indicated that the device is highly selective for PA detection. Then, the electrochemical sensor was applied to a real sample, demonstrating excellent performance for the quantification of PA in guava seed oil, showing excellent selectivity, sensitivity, and high stability.