Quantum dot-based biomimetic fluorescence immunoassays for enrofloxacin detection in animal-derived foods.

Long-term consumption of foods with excessive enrofloxacin (ENRO) residues may cause the accumulation of ENRO in the human body, thus damaging human health. In this study, quantum dot-based biomimetic fluorescence immunoassays were used for enrofloxacin detection in food of animal origin. Under the most suitable conditions, the detection limit (IC) of the method in standard solution was 0.

Development of two novel ELISAs based on Prussian blue nanoparticles for ultrasensitive detection of norfloxacin in milk.

The development of traditional enzyme-linked immunosorbent assay (ELISA) systems for the detection of small-molecule residues in foods is limited because of the poor stability of biological enzymes and the lower sensitivity of absorption-based signals. Herein, two ELISAs based on Prussian blue nanoparticles (PBNPs) were developed to establish ultrasensitive and stable methods for detecting norfloxacin (NOR) in milk. The results show that the detection limit (IC) of NOR was 0.

Simultaneous detection of enrofloxacin and florfenicol in animal-derived foods based on fluorescence quenching BELISA and a nanozyme catalytic strategy.

Enrofloxacin (ENRO) and florfenicol (FF) are animal-specific drugs, but they present great harm to human health. Therefore, it is essential to rapidly and accurately detect ENRO and FF in animal-derived foods simultaneously. Herein, dual-template molecular imprinted polymers (MIPs) with specific recognition of ENRO and FF were prepared, meanwhile, the molar ratios of templates to monomer and cross-linker were optimized and then applied as a bionic antibody to experiment.

Application of molecular imprinting technology based on new nanomaterials in adsorption and detection of fluoroquinolones.

Irrational use of fluoroquinolones (FQs) can lead to allergic reactions, adverse reactions to the heart and damage of the liver; thus, it is of great significance to establish rapid, sensitive and accurate detection methods for FQs. Molecularly imprinted polymers (MIPs) with specific structures synthesized by molecular imprinting technology (MIT) are widely used for the detection of FQs due to their high specificity, high sensitivity and stable performance. Recently, new functional nanomaterials with different morphologies and sizes, which can provide rich sites for surface chemical reactions, have attracted more and more attention of the researchers.

Water and alcohol extracts from Diaphragma juglandis on anti-fatigue and antioxidative effects in vitro and vivo.

Background: To estimate the anti-fatigue and antioxidative effects of water and alcohol extracts from Diaphragma juglandis (DJ), H O -treated HepG2 cells were used as an in vitro model to determine the total antioxidant capacities of these two extracts, and behavioral tests on mice and biochemical assay were performed via in vivo experiments.

Results: The results indicate that both extracts possess remarkable HepG2 protective capacities and were capable of scavenging 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) similar to vitamin C. Furthermore, they could significantly prolong the bar climbing time and force swimming time, as well as decrease the serum urea nitrogen and increase the lactate dehydrogenase level and glycogen content.

Ovarian Index of KM Mice Influenced by Longer Term Consumption of Microwave-Heated Milk.

Abstract: Microwave technology has been widely used in the food industry, but the effect of microwave-heated food on human health is being questioned. Female KM mice were chosen to be treated with microwave-heated milk (MM), and reproductive markers such as litter size, birth rate, survival rate, and ovarian index were evaluated. With longer term feeding, the reproductive status (body weight, birth rate, litter size, neonatal survival rate, interpregnancy interval, and brain superoxide dismutase and catalase activity) of KM mice treated with MM did not significantly change except for the ovarian index of first-generation mice, which was decreased significantly compared with the control group and the group given electrically heated milk.

Fluorescent quenching immune chromatographic strips with quantum dots and upconversion nanoparticles as fluorescent donors for visual detection of sulfaquinoxaline in foods of animal origin.

In this study, two novel fluorescence quenching immune chromatographic strips (FQICS) were developed to detect sulfaquinoxaline (SQX) in foods of animal origin. These proposed FQICSs were based on fluorescence resonance energy transfer (FRET) from fluorescence donors (quantum dots or upconversion nanoparticles) to fluorescence acceptors (colloidal gold nanoparticles). Compared with traditional colloidal gold-based immune chromatographic strips (ICS), these FQICSs showed positive correlation between the fluorescent signals and the targets, and allowed user to get test results from weak fluorescent signals.

Development of an Enzyme-Linked Immunosorbent Assay for the Detection of Tyramine as an Index of Freshness in Meat and Seafood.

A competitive indirect enzyme-linked immunosorbent assay (ciELISA) using a polyclonal antibody was developed to detect tyramine in meat and seafood. This ciELISA had a 50% inhibition concentration (IC) of 0.20 mg/L and a limit of detection (LOD) of 0.

Upconversion Nanoparticles and Monodispersed Magnetic Polystyrene Microsphere Based Fluorescence Immunoassay for the Detection of Sulfaquinoxaline in Animal-Derived Foods.

A novel fluorescence immunoassay for detecting sulfaquinoxaline (SQX) in animal-derived foods was developed using NaYF4:Yb/Tm upconversion nanoparticles (UCNPs) conjugated with antibodies as fluorescence signal probes, and monodisperse magnetic polystyrene microspheres (MMPMs) modified with coating antigen as immune-sensing capture probes for trapping and separating the signal probes. Based on a competitive immunoassay format, the detection limit of the proposed method for detecting SQX was 0.1 μg L(-1) in buffer and 0.

A novel and sensitive fluorescence immunoassay for the detection of fluoroquinolones in animal-derived foods using upconversion nanoparticles as labels.

A novel fluorescence immunoassay to detect fluoroquinolones in animal-derived foods was developed for the first time by use of upconversion nanoparticles as signal-probe labels. The bioassay system was established by the use of coating-antigen-modified polystyrene particles as immune-sensing probes for separation and anti-norfloxacin monoclonal antibody conjugated with carboxyl-functionalized NaYF4:Yb,Er upconversion nanoparticles which were prepared via a pyrolysis method and a subsequent ligand exchange process as fluorescent-signal probes (emission intensity recorded at 542 nm with excitation at 980 nm). Under optimized conditions, detection of fluoroquinolones was performed easily.