To identify adulterated camel meat in emerging markets, there is an urgent need for sensitive, rapid, and convenient detection methods. In this study, a novel fluorescent sensing platform was developed to effectively identify pork components adulterated in camel meat by regulating the surface charge properties of MIL-101(Cr). Our data demonstrated that the modification of polyethylenimine (PEI) had minimal impact on the crystal structure of MIL-101(Cr). However, it significantly affected the adsorption behavior of MIL-101(Cr) towards 6-carboxyfluorescein (FAM) labelled DNA, thereby influencing the response of fluorescence quenching-recovery. Under optimal conditions, the proposed turn-on fluorescent biosensor, based on PEI-MIL-101(Cr) exhibited high sensitivity with a detection limit of 42 pM. It also demonstrated excellent selectivity for specific target DNA, successfully detecting a pork fraction of 0.45 % (w/w) in camel meat. This study was aimed to provide a fresh perspective on the potential application of functional materials derived from metal-organic frameworks in detecting food adulteration .
Jianmei Li,Yuting Yin,Haiyu Li,Zongyao Zhao,Mengqin Xiang,Yong Tang,Qi Sun
The escalating economic and ethical concerns associated with camel meat adulteration using cheaper horsemeat necessitate the development of rapid, on-site detection technologies that overcome the limitations of conventional laboratory-based methods. In this study, a portable electrochemical DNA biosensor was fabricated by integrating a polydopamine (PDA)-modified screen-printed carbon electrode (SPCE) with a nucleic acid-functionalized UIO-66(Zr) metal-organic framework (MOF). The PDA coating facilitated stable, covalent immobilization of DNA capture probes through Schiff base reactions, while the UIO-66(Zr) MOF functioned as a high-capacity signal amplifier owing to its large surface area and intrinsic redox activity. This synergistic architecture enabled ultrasensitive detection, achieving a limit of 3.57 pmol/L for horsemeat DNA and 0.5 g/kg adulteration in camel meat blends—significantly surpassing the performance of existing detection methods. The biosensor exhibited excellent specificity by distinguishing single-base mismatches, along with high reproducibility (RSD = 4.12%), operational stability over 15 days, and accurate recovery rates ranging from 91.7% to 112.4% in spiked samples. Its disposable electrode format, cost-effectiveness, and compatibility with portable potentiostats underscore its strong potential for on-site meat authentication. Overall, this work provides a practical and scalable solution to combat meat fraud in resource-limited settings and establishes a versatile MOF-electrode nanoassembly platform for advanced food safety monitoring.
Traditional DNA purification methods face limitations in efficiency and complexity, particularly for food authenticity verification. To address this, we developed novel magnetic nanocomposites by integrating polydopamine-coated Fe 3 O 4 nanoparticles (Fe 3 O 4 @PDA) with zirconium-based metal-organic frameworks (Zr-MOFs) functionalized via varying organic ligands (terephthalic acid, 2-aminoterephthalic acid, and 1,2,4-benzenetricarboxylic acid). The resulting materials—MUIO-66, MUIO-66-NH₂, and MUIO-66-COOH—were characterized for structure, magnetism, and DNA adsorption performance. MUIO-66-COOH exhibited superior efficiency, achieving >80 % DNA recovery from camel meat under optimized conditions (25 °C, 10 min), outperforming commercial kits. Adsorption kinetics and isotherms revealed a multilayer process (Freundlich model) governed by pseudo-second-order kinetics, driven by "salt-bridge" interactions between DNA phosphate groups and surface carboxyl moieties. The method demonstrated high precision (RSD = 2.75 %), reproducibility, and reusability (>81 % efficiency after 5 cycles). This work establishes a rapid, ligand-tunable magnetic solid-phase extraction (MSPE) platform for high-quality DNA extraction, advancing biosensing applications in food authenticity.
危险品化学品经营许可证（带存储）