Porphyrin NanoMOFs as a catalytic label in nanozyme-linked immunosorbent assay for Aflatoxin B1 detection

Food safety is a global problem, and methods to reliably and sensitivity detect contaminants could be transformative. Herein, we synthesized a novel Porphyrin NanoMoFs (NanoPCN-223(Fe)) with excellent dispersion and peroxidase-like activity. The Km value of NanoPCN-223(Fe) was 2.0 × 10-4 M toward the H2O2 substrate during the catalytic process. We use the NanoPCN-223(Fe) to construct an enhanced dispersion MOF-linked immunosorbent assay (Ed-MOFLISA) to sensitive detect AFB1 in milk. The optimized Ed-MOFLISA displayed a broad quantitative range from 0.05 to 10 ng/mL and a limit of detection of 0.003 ng/mL. Spiked peanut and soy milk recovery ranged from 91.22% to 97.63%. Intra-assay and inter-assay coefficient of variation values ranged from 0.78 to 3.85%, demonstrating the outstanding reproducibility and accuracy of Ed-MOFLISA. We applied the Ed-MOFLISA assay to test the milk samples, demonstrating its potential use for monitoring food quality.