Work

In-situ synthesized porphyrinic zirconium MOF-derived multilayered nanocomposite probe for ultra-sensitive immunosensor

Year: 2025

Type: article

Abstract: Aflatoxin B 1 (AFB 1 ) is a major concern due to its widespread contamination and potential harm. Colorimetric lateral flow immunoassays (LFIAs) incorporating gold nanoparticles (AuNPs) are widely used for on-site analyte detection. However, it remains challenging due to the limited brightness of AuNPs. Herein, we introduce an immunosensor for highly sensitive AFB 1 detection utilizing a multilayered nanocomposite probe (PCN-224@Fe 3 O 4 @PDA@Ab/HRP), created by sequentially modifying Fe 3 O 4 nanoparticles, polydopamine layers, and horseradish peroxidase on a porphyrinic metal-organic framework, which offers magnetic separation, high signal brightness, and strong catalytic activity. Integrated with a competitive assay format, the immunosensor achieved ultrasensitive detection of AFB 1 , with a detection range of 0.003–3 ng/mL and a limit of detection (LOD) of 0.0014 ng/mL. Moreover, our immunosensor exhibited satisfactory recoveries and successful detection of AFB 1 in cereal samples. Therefore, this work offers innovative strategies for designing multi-functional nanocomposite probes that enhance detection sensitivity, holding great promise in food safety monitoring. • The PCN-224@Fe 3 O 4 @PDA@Ab/HRP with colorimetric magnetic catalysis was prepared. • PCN-224@Fe 3 O 4 @PDA could load numerous HRP to realize remarkably-enhanced signals. • The PCN-224@Fe 3 O 4 @PDA@Ab/HRP-based immunosensor was developed for AFB 1 detection. • The LOD of 0.0014 ng/mL, as well as satisfactory recoveries were realized. • The immunosensor is applicable for rapid screening of AFB 1 in agro-products.

Source: Food Chemistry X

DOI: 10.1016/j.fochx.2025.103059