Applications of metal-organic framework (MOF)-based sensors for food safety: Enhancing mechanisms and recent advances

Increasing requirements for rapid and reliable food safety control demands new sensing techniques with excellent performance. Metal-organic framework (MOF), as a class of emerging porous crystalline materials, has advantages of uniform structures, ultrahigh porosity, tunable composition, and easy-to-functionalize surface. In recent years, MOF-based materials have been extensively explored in developing sensors for food safety control. In this review, the applications of MOFs in recent 7 years as sensing material in fabricating sensors, such as luminescent, electrical, electrochemiluminescent, colorimetric, and surface-enhanced Raman scattering sensors, for detecting food risk factors including veterinary drugs, pesticide residues, pathogens, mycotoxins, heavy metals, illegal additives, food additives, and other contaminants are summarized, compared and discussed based on the working mechanisms. The major limitations of each sensing types and the enhancing mechanisms of MOFs in resolving such major issues are discussed. Current limitations faced by MOF-based materials and future trends are also presented. MOF-based materials have exhibited outstanding sensing performance when applied in food safety control. Although MOF-based materials have demonstrated great potential, more work is still needed before they can be widely used in practical applications. With the development of new synthesis and modification techniques, sensors using MOFs as sensing materials are promising to further improve the food safety sensing efficiency.