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Food safety is a critical public concern, and has drawn great attention in society. Consequently, developments of rapid, robust, and accurate methods and techniques for food safety evaluation and control are required. As a nondestructive and convenient tool, near-infrared spectroscopy (NIRS) has been widely shown to be a promising technique for food safety inspection and control due to its huge advantages of speed, noninvasive measurement, ease of use, and minimal sample preparation requirement. This review presents the fundamentals of NIRS and focuses on recent advances in its applications, during the last 10 years of food safety control, in meat, fish and fishery products, edible oils, milk and dairy products, grains and grain products, fruits and vegetables, and others. Based upon these applications, it can be demonstrated that NIRS, combined with chemometric methods, is a powerful tool for food safety surveillance and for the elimination of the occurrence of food safety problems. Some disadvantages that need to be solved or investigated with regard to the further development of NIRS are also discussed.

In the past ten years, as a novel and prospective nanomaterials, carbon dots have acquired tremendous attention for their unique optical and physicochemical properties, high compatibility and low cost, as well as great potential in sensing area. This review aims to present the current detecting principles based on carbon dots and other nano biological technologies, involving fluorescence quenching and recovery mechanisms. The synthetic and modificatory approaches in making carbon dots including top-down and bottom-up methods, as well as surface passivation and heteroatom doping ways are introduced. Their applications in food area, concerning detection of nutrients, restricted or banned substances as well as foodborne pathogenic bacteria and the toxins secreted are discussed. Finally, the difficulties to be overcome or problems to be solved are presented, and other novel techniques to combine with carbon dots to obtain more stable and specific nanosensors in various fields are proposed. Although carbon dots based sensors have shown the potential in sensing aspect of food area, as food samples are complex in compositions that may cause interferences, more novel techniques are needed to combine with carbon dots to develop sensitive and specific sensing probes.

Cobalt-nitrilotriacetic acid (Co(III)-NTA) chemistry is a recognized approach for oriented patterning of His6tagged bioreceptors. We have applied the matching strategy for the first time on an SPR platform, namely the commercialized FO-SPR. To accomplish this, His6-tagged bioreceptor (scFv-33H1F7) and its target PAI-1 were used as a model system, after scrutinizing the specificity of their interaction. When benchmarked to traditional carboxyl based selfassembled monolayers (SAM), NTA allowed (1) more efficient FO-SPR surface coverage with bioreceptors compared to the former and (2) realization of thus far difficult-to-attain label-free bioassays on the FO-SPR platform in both buffer and 20fold diluted human plasma. Moreover, Co(III)-NTA surface proved to be compatible with traditional gold nanoparticlemediated signal amplification in the buffer as well as in 10-fold diluted human plasma, thus expanding the dynamic detection range to low ng/mL. Both types of bioassays revealed that scFv-33H1F7 immobilized on the FO-SPR surface using different concentrations (20, 10 or 5 μg/mL) had no impact on the bioassay sensitivity, accuracy or reproducibility despite the lowest concentration effectively resulting in close to 20% fewer bioreceptors. Collectively, these results highlight the importance of Co(III)-NTA promoting the oriented patterning of bioreceptors on the FO-SPR sensor surface for securing robust and sensitive bioassays in complex matrices, both in label-free and labelled formats.

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