A highly sensitive AgNPs/Ni3(HHTP)2 SERS substrate for the detection of food additives and pesticide residues

Abstract

Abstract Surface-enhanced Raman scattering (SERS) is a spectroscopic technique that utilizes nanostructured substrates and is vital in food analysis. However, enhancing SERS substrates’ sensitivity and applicability remains a challenge. The conductive metal organic framework Ni3(HHTP)2 has been widely used due to its excellent conductivity and porous structure. This study combines Ni3(HHTP)2’s charge transfer properties with AgNPs’s localized surface plasmon resonance to create a highly sensitive SERS substrate. Firstly, rod-shaped Ni3(HHTP)2 was prepared, and then a monolayer of AgNPs film was loaded on its surface. The substrate can detect crystal violet at a concentration of 10−14 M, and Ni3(HHTP)2 has a flat structure, coupled with AgNPs film, provided good detection uniformity (Relative Standard Deviation, RSD = 10.09%). Moreover, the substrate successfully detected food additives solutions, as well as the pesticide residues on fruit surfaces by bending. This substrate offers a rapid monitoring solution for food safety, facilitating real-time detection of contaminants in daily life.