Biomimetic enzyme electrochemical sensor based on nanocomposites of carbon black coated ZnO nanoflowers/poly (L-phenylalanine) for food colorant analysis

Developing simple and rapid methods for the detection of colorant content in foods is essential to mitigate their negative health effects on human. Hence, we constructed a biomimetic enzyme electrochemical sensor to efficiently detect sunset yellow using the nanocomposites of carbon black coated zinc oxide nanoflowers/poly (L-phenylalanine) (CB@ZnO/PLPA). CB was ultrasonically coated onto the surface of ZnO nanoflowers synthesized by two-step wet chemical method, and subsequently combined with PLPA for signal amplification. The synergistic effect of CB@ZnO/PLPA resulted in large electrochemical active area and excellent electrical conductivity. The investigations demonstrated a wide linear range of 0.5–200 μmol/L, a low detection limit of 0.07 μmol/L (S/N = 3) with a sensitivity of 9.272 μA μM −1  cm −2 , by the effective synergy between carbon black @ zinc oxide (CB@ZnO) and poly (L-phenylalanine) (PLPA). CB@ZnO/PLPA sensor showed satisfactory performance for SY detection and its feasibility was verified in real samples detection. In this paper, a simple and efficient electrochemical sensor for SY detection was developed, offering significant potential for widespread application in food analysis.