Novel Immunosensor Based on Metal Single-Atom Nanozymes with Enhanced Oxidase-Like Activity for Capsaicin Analysis in Spicy Food.

Capsaicin (CAP) is a primary indicator for assessing the level of pungency. Herein, iron-based single-atom nanozymes (SAzymes) (Fe/NC) with exceptional oxidase-like activity were used to construct an immunosensor for CAP analysis. Fe/NC could imitate oxidase actions by transforming O to O radicals in the absence of hydrogen peroxide (HO), which could avoid complex operations and unstable results.

A novel magnetic resonance tuning-magnetic relaxation switching sensor based on Gd-MOF/USPIO assembly for sensitive and convenient aflatoxin B1 detection.

Aflatoxin B1 (AFB1) can accumulate in different organs or tissues and seriously harm humans. Traditional magnetic relaxation switching (MRS) sensors have relatively low sensitivity, but are complex to use. Rapid small-trace molecule analysis in complex samples is challenging.

Novel rapid detection of melamine based on the synergistic aggregation of gold nanoparticles.

A simple and rapid colorimetric method for the detection of melamine in milk samples is described. Polythymidine oligonucleotide was adsorbed on to the surface of gold nanoparticles (AuNPs), protecting it from aggregation. In the presence of melamine, polythymidine oligonucleotide combined with melamine formed a double-strand DNA-like structure, allowing AuNPs aggregation.

A novel method based on Ag-Au nanorings with tunable plasmonic properties for the sensitive detection of amantadine.

To prevent the toxic effect of amantadine (AMD) on humans, a sensitive and direct detection method is required. The conventional enzyme-linked immunosorbent assay (ELISA) usually shows a monochromatic gradient color variation with the concentration of the target; hence, it is not a sensitive method for naked-eye detection. In this work, Ag-Au nanorings with highly tunable plasmon properties were synthesized as colorimetric nanosensors.

I/I-mediated fluorescence quenching of an Ag-doped gold nanocluster-based immunoassay for sensitive detection of Escherichia coli O157:H7 in milk.

Escherichia coli O157:H7 is a type of hazardous bacteria in the field of food safety. A sensitive and effective method is urgently needed to detect it, avoiding enormous harm for the human health. In this study, we synthesized stable Ag-doped gold nanoclusters (Ag-AuNC) with a fluorescence intensity 4.

Development of a label-free plasmonic gold nanoparticles aggregates sensor on the basis of charge neutralization for the detection of zearalenone.

Mycotoxin contamination of corn has been considered a serious problem because it can accumulate in different organs or tissues via ingestion or skin contact and cause several health problems in humans. We have constructed a label-free, colorimetric, and fluorescence dual-channel sensing platform for the detection of zearalenone. Here, we demonstrate that plasmonic gold nanoparticles aggregates could be rapidly formed on the basis of charge neutralization by positively charged SYBR Green I.

Lateral flow immunoassay based on dual spectral-overlapped fluorescence quenching of polydopamine nanospheres for sensitive detection of sulfamethazine.

Herein, we propose a lateral flow immunoassay (LFIA) based on the dual spectral-overlapped fluorescence quenching of polydopamine nanospheres (PDANs) caused by the inner filter effect to sensitively detect sulfamethazine (SMZ). The fluorescence quenching LFIA device consists of four parts: absorbent pad, polyvinyl chloride pad, sample pad, and nitrocellulose membrane. Compared with traditional quenchers such as gold nanoparticles (AuNPs) with single spectral-overlapped quenching ability, PDANs can quench the excitation light and emission light of three fluorescence donors (aggregation-induced emission fluorescent microsphere, AIEFM; fluorescent microsphere, FM; and quantum dot bead, QB).

Therapeutic implications of functional tea ingredients for ameliorating inflammatory bowel disease: a focused review.

Inflammatory bowel disease (IBD) is a chronic gastro-intestinal disorders of unknown etiology. There are several drugs approved for treating IBD patients with active disease, including first-line use of aminosalicylates, and secondary choices of immunomodulators and other therapies. These medications might manage disease symptoms, but have also shown significant side-effects in IBD patients.

Immunochromatographic assay based on time-resolved fluorescent nanobeads for the rapid detection of sulfamethazine in egg, honey, and pork.

Background: Sulfamethazine (SMZ), a veterinary drug widely used in animal husbandry, is harmful to human health when excess residues are present in food. In this study, a fast, reliable, and sensitive immunochromatographic assay (ICA) was developed on the basis of the competitive format by using time-resolved fluorescent nanobeads (TRFN) as label for the detection of SMZ in egg, honey, and pork samples.

Results: Under optimized working conditions, this method had limits of detection of 0.

Sensitive immunoassays based on a monoclonal antibody for detection of marbofloxacin in milk.

Marbofloxacin (MBF) is a key class of synthetic fluoroquinolone antibiotic that is commonly used as a veterinary drug. However, excess residue of MBF in animal-derived food samples, such as milk, is harmful to consumers. In this study, 4 mAb against MBF, namely, M4E3, M7A6, M3C7, and M5C6, were produced.

Green Enzyme-Linked Immunosorbent Assay Based on the Single-Stranded Binding Protein-Assisted Aptamer for the Detection of Mycotoxin.

In this work, a green enzyme-linked immunosorbent assay (ELISA) based on the single-stranded binding protein (SSB)-assisted aptamer was designed for biosensing applications. Combined with the biotin-streptavidin (SA) system and the high catalytic activity of horseradish peroxidase (HRP), this SSB-assisted aptamer sensor was applied for the detection of aflatoxin B1, ochratoxin A, and zearalenone. In this novel ELISA, mycotoxin-protein conjugations were replaced by SSB to avoid the hazard of mycotoxin, whereas antibodies were replaced by aptamer to avoid the complex and tedious preparation of antibodies.

Hot-water extract of ripened Pu-erh tea attenuates DSS-induced colitis through modulation of the NF-κB and HIF-1α signaling pathways in mice.

Tea consumption has been found to be associated with low incidence of inflammatory bowel disease in Asian countries. However, there is very limited knowledge of such potential protection and its underlying mechanism. Ripened Pu-erh tea (RPT) belongs to the variety of microbial fermented tea, but its function regarding anti-inflammation remains unclear.

Using molecular descriptors for assisted screening of heterologous competitive antigens to improve the sensitivity of ELISA for detection of enrofloxacin in raw milk.

The use of the heterologous competitive strategy has become a vital method to improve the sensitivity of ELISA. In this work, we prepared an anti-enrofloxacin (ENR) mAb with ENR-bovine serum albumin (BSA) as immunogen. The molecular descriptors of quinolones were then used to screen heterologous coating antigens for the detection of ENR based on an ensemble learning method to improve the sensitivity of the ELISA.

Novel ELISA based on fluorescent quenching of DNA-stabilized silver nanoclusters for detecting E. coli O157:H7.

Escherichia coli O157:H7 (E. coli O157:H7) is a potential threat to human health; thus, a rapid and sensitive method for detecting it is necessary. We designed a single-stranded DNA that contained an appended block and anchoring block.

Lateral flow immunoassay integrated with competitive and sandwich models for the detection of aflatoxin M and Escherichia coli O157:H7 in milk.

Pathogens, mycotoxins, or antibiotics may exist in a food sample. Micro- and macromolecular substances must be detected quickly. A rapid and convenient lateral flow immunoassay (LFI) integrated with competitive and sandwich models was developed to detect micro- and macromolecular substances.

Nanozyme-based lateral flow assay for the sensitive detection of Escherichia coli O157:H7 in milk.

Lateral flow assay (LFA) has been applied in many fields due to its relative ease of use and cost-effectiveness. However, it has low sensitivity and its applications are limited. Probe materials play a significant role in improving the detection efficiency and sensitivity of LFA.

Specific colorimetric ELISA method based on DNA hybridization reaction and non-crosslinking gold nanoparticles aggregation for the detection of amantadine.

Amantadine (AMD), a banned antiviral veterinary drug, is still being abused. This study developed a novel enzyme linked immunosorbent assay for the colorimetric detection of AMD involving DNA hybridization reaction and non-crosslinking gold nanoparticles (AuNPs) aggregation. Accordingly, the Primer 1-AuNPs-anti-AMD monoclonal antibody (mAb) could be captured by AMD artificial antigen on ELISA wells.

Novel immunochromatographic assay based on Eu (III)-doped polystyrene nanoparticle-linker-monoclonal antibody for sensitive detection of Escherichia coli O157:H7.

Colloidal gold immunochromatographic assay (ICA) has poor sensitivity when used for Escherichia coli O157:H7 (E. coli O157:H7) detection. Eu (III)-doped polystyrene nanoparticle (EuNP) has a large range of stokes shift, long decay time, and wide excitation spectrum and narrow emission spectra.