Herein, we report the fabrication of a compact voltammetric sensor for the sensitive and selective determination of N-nitrosodiphenylamine (NDPhA) based on a screen-printed graphene electrode modified with a molecularly imprinted polymer coating on a palladium nanoparticle core (PdNPs@MIP/SPGrE). In addition, a novel approach for 3D-imprinting of NDPhA on the PdNPs surface is presented. PdNPs were first synthesized by chemical reduction using sodium borohydride. Then, Core-shell polymerization was achieved by successively coating the surface of PdNPs with poly(vinylpyrrolidone) and terminating with an MIP consisting of poly(N-Isopropylacrylamide)-co-trimethylolpropane trimethacrylate.

Morphological, structural, and electrochemical characterization reveals that the as-prepared micro-sized spherical PdNPs@MIP has a uniform, high electro-catalytic activity and a specific surface area with many NDPhA imprinted sites. We constructed the compact NDPhA imprinted sensor by coating the SPGrE surface with PdNPs@MIP. Quantitative analysis was performed by linear sweep anodic stripping voltammetry (LSASV) using a deposition potential of +0.02 V for 60 s. The linear working ranges for NDPhA measurements were 0.01–0.1 μM (r² = 0.996) and 0.1–100 μM (r² = 0.992) with corresponding sensitivities of 51.935 and 0.821 (μA s) µM⁻¹, respectively. The system provides a good precision of %RSD 1.67% with an estimated detection limit (3S_b, n = 3) of 0.0013 μM. The intraday and inter-day accuracy (%bias) of the certified reference material (CRM) are −0.74% and −1.01%, respectively. We demonstrate the successful application of the fabricated compact sensor to determine NDPhA in beverage and synthetic samples. The compact NDPhA imprinted sensor can provide an alternative approach to food quality control.