Engineered MXene as An Analytical Tool for Health Risk Assessment of Heavy Metals

Abstract

Two-dimensional MXenes are attractive materials because of their metallic conductivity, abundant surface terminations, and high aspect ratio that can be coupled with organic molecules and magnetic structures to produce multifunctional architectures. Here, we engineer a Diphenylthiocarbazone-grafted magnetic MXene, DTZ–Ti3C2@Fe3O4, through a stepwise synthesis of magnetic nanoparticles on Ti3C2 nanosheets and subsequently grafts Diphenylthiocarbazone covalently onto surface functional groups. This route yields a hierarchically structured 2D hybrid in which (i) Ti3C2 provides an extended, mechanically strong active scaffold, (ii) well-dispersed magnetic domains without shielding the MXene surface, and (iii) the immobilized Diphenylthiocarbazone moieties as densely packed, multidentate soft-donor (N,S) chelation sites. This structure is used as an analytical tool to investigate the health risk assessment of heavy metal consumption. Under optimized conditions and acceptable figures of merits (detection limits of 0.085 ng mL-1 (Cd2+) and 0.87 ng mL-1 (Pb2+) with linear ranges of 0.3-40 µg L-1 and 3-80 µg L-1, a preconcentration factor (PF) of 100), the concentration of heavy metals in food samples was quantified at trace levels and was fed directly into estimated daily intake (EDI) , target hazard quotient (THQ), the Total Cumulative Health Risk (TTHQ), and lifetime cancer risk (CR) calculations using body-weight and consumption-rate scenarios. Results show TTHQ < 1 and CR < 1×10-4 for Cd and Pb in analyzed foods samples. To the best of our knowledge, this study represents the first covalently grafted Diphenylthiocarbazone- magnetic MXene tailored specifically for trace-metal chelation and quantitative health risk assessment of heavy metals and food-safety evaluation. This report demonstrates that MXenes can serve as a practical analytical platform for population-relevant risk assessment, and not merely trace detection.