**Background:** Nanotechnology, which exploits atomic and molecular interactions at the nanoscale and microscale, is increasingly applied in food science to improve the detection of food safety hazards and spoilage. This editorial introduces a Research Topic focused on the latest trends in nano/biotechnology-based analytical methods for detecting hazardous substances in food, specifically electrochemical and optical approaches.
**Methods:** The editorial reviews multiple original studies published within the Research Topic. For electrochemical methods: Yang L. et al. developed a sensitive electrochemical method for guanine detection by integrating vertically-ordered mesoporous silica films (VMSF) on indium tin oxide (ITO) with tris(2,2'-bipyridine) ruthenium (III) [Ru(bpy)32+] as a redox mediator. VMSF electrostatically accumulates Ru(bpy)32+, which acts as an electron shuttle between guanine and the ITO electrode. Luo et al. established a dual-mode electrochemical (EC) and electrochemiluminescence (ECL) method for antimicrobial peptide analysis, using Ru(bpy)32+@liposomes as signal probes that leak from nisin-damaged liposomes and are enriched by VMSF/ITO electrodes. Yang T. et al. prepared a low aspect-ratio SiN nanopore with PDMS coating to observe bacterial translocation events, identifying three foodborne pathogens (Salmonella enterica, Listeria monocytogenes, and Escherichia coli) based on changes in electric pulse signals. For optical methods: Wang et al. developed a spectrophotometric and Rayleigh scattering (RRS) method for trace Ag(I) detection, where Ag(I) reacts with erythrosine to form nanoparticles at pH 4.4–4.6, decreasing absorbance and increasing RRS signal. Lv et al. used AuMOF as a nanoprobe to establish an RRS-energy transfer method for sulfur dioxide detection in food, where basic rhodopsin (BF) on AuMOF surface decreases RRS intensity at 330 nm, and sulfite reacts with BF to form a colorless product (SBF), enhancing the RRS peak. Zhi et al. created a MXene catalytic fluorescence/absorption dual-mode aptamer sensor for trace Pb2+ detection, where Ti3C2 nanosheets (NS) catalyze TMB oxidation producing fluorescence at 415 nm and absorption at 295 nm, but Pb2+ aptamer (Aptpb) adsorbed on NS inhibits catalytic activity; target Pb2+ specifically binds Aptpb, releasing NS and enhancing signal. Shahdeo et al. developed a microfluidic colorimetric device coupled with AuNPs and a 36-mer OTA-specific aptamer to detect Ochratoxin A (OTA), where AuNP size changes in the presence of OTA, and absorbance ratios of A630 and A520 are used for quantification.
**Key Results:** The reviewed studies collectively demonstrate that nanomaterials significantly enhance analytical performance. VMSF-modified electrodes provide excellent molecular selectivity and anti-fouling ability for direct analysis in complex samples. Nanopore-based sensors achieve high temporal-spatial resolution for bacterial identification. Optical methods using nanomaterials (erythrosine-Ag nanoparticles, AuMOF probes, MXene nanosheets, AuNP-aptamer complexes) enable sensitive detection of heavy metals (Ag+, Pb2+), food additives (sulfur dioxide), and mycotoxins (OTA) through various signal transduction mechanisms including absorbance changes, RRS intensity shifts, fluorescence enhancement, and colorimetric readouts.
**Clinical Implications:** While this is an editorial reviewing food safety detection methods rather than a clinical study, the implications for public health are substantial. Improved detection of foodborne pathogens (Salmonella enterica, Listeria monocytogenes, Escherichia coli), toxins (Ochratoxin A), heavy metals (Ag+, Pb2+), and food spoilage markers (guanine, sulfur dioxide) can enhance food safety monitoring, reduce foodborne illness, and protect consumers from chronic exposure to hazardous substances. The simplified operation and improved speed, efficiency, and accuracy of these nano/biotechnology-based methods could enable broader implementation of food safety testing across the supply chain.