Development of an immunochromatography assay for salinomycin and methyl salinomycin in honey

A Review on Pretreatment and Analysis Methods of Polyether Antibiotics in Complex Samples

Polyether antibiotics (PAs) are the anti-coccidiosis drugs used for treating and preventing coccidiosis. Studies show the residues of these antibiotics in food cause adversities and threaten human health. PAs thus need robust, rugged, and accurate methods for their analysis. This review encompasses pretreatment and detection methods of PAs in diverse matrices since 2010. Both conventional and developed methods are part of the pretreatments, such as dispersive liquid-liquid microextraction, solid-phase extraction, solid-phase microextraction, solvent front position extraction, QuEChERS (Quick Easy Cheap Effective Rugged and Safe), supercritical fluid extraction, and others. The analysis methods involve liquid chromatography coupled with detectors, sensors, etc. The pros and cons of various techniques for PAs have been discussed and future tendencies are proposed.

Application of nano-antibiotics in the diagnosis and treatment of infectious diseases

Infectious diseases are the leading cause of death worldwide. Thus, nanotechnology provides an excellent opportunity to treat drug-resistant microbial infections. Numerous antibiotics have been used to inhibit the growth and kill of microbes, but the development of resistance and the emergence of side effects have severely limited the use of these agents. Due to the development of the nanotechnology, nanoparticles are widely used as antimicrobials. Silver and chitosan nanoparticles have antifungal, antiviral and antibacterial properties, and many studies confirm the antifungal properties of silver nanoparticles. Nowadays, the use of nanoparticles in the diagnosis and treatment of infectious diseases has developed due to less side effects and also the help of these particles in effective drug delivery to the target tissue. Liposomes are also used as carriers of drug delivery, genes, and modeling of cell membranes in both animals and humans. The ability of these liposomes to encapsulate large amounts of drugs, minimize unwanted side effects, high effectiveness and low toxicity has attracted the interest of researchers. This review article examines recent efforts by researchers to identify and treat infectious diseases using antimicrobial nanoparticles and drug nano-carriers.

A gold nanoparticle based colorimetric sensor for the rapid detection of Yersinia enterocolitica serotype O:8 in food samples

Foodborne diseases from Yersinia enterocolitica serotype O:8 represent global public health problems.

Rapid colloidal gold immunochromatographic assay for the detection of SARS-CoV-2 total antibodies after vaccination

An epidemic caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2) spread globally in just a few months. To help prevent the further spread of the virus, millions of people...

Detection of salinomycin and lasalocid in chicken liver by icELISA based on functional bispecific single-chain antibody (scDb) and interpretation of molecular recognition mechanism

Salinomycin (SAL) and lasalocid (LAS) are widely used as ionophore antibiotics for coccidiosis control. However, their common use as feed additives has led to the occurrence of feed cross-contamination, which has toxic effects on non-target animals. There have been few reports on multiple-residue detection for SAL and LAS in recent years. In this study, two single-chain antibody fragments (scFvs) capable of specifically recognizing SAL and LAS were constructed. Using LAS-scFv and SAL-scFv as parent antibodies, a complete bispecific single-chain diabody (scDb) against both LAS and SAL was built using splicing by overlap extension polymerase chain reaction (SOE-PCR). In addition, the key amino acid sites and interaction energy of antibody variable regions for small-molecule recognition were preliminarily studied by homology modeling and molecular docking. Finally, IC₅₀ values of 12.9 and 8.6 ng/mL, with a linear range of 6.9-24.0 and 4.7-16.0 ng/mL, were obtained for LAS-scFv and SAL-scFv, respectively. An indirect competitive enzyme-linked immunosorbent assay (icELISA) method was established using scDb to obtain an IC₅₀ of 3.5 ng/mL for LAS and 4.1 ng/mL for SAL, which showed better sensitivity and specificity than those of the parent scFv antibodies. The recoveries of LAS and SAL in chicken liver were 89.2-92.7%(CV<4.7%) and 88.6-90.2% (CV<6.8%)), respectively.

An immunochromatographic sensor for ultrasensitive and direct detection of histamine in fish

To ensure food quality and prevent histamine (HA) toxicity, a rapid and direct method of detecting HA is required. In this work, we prepared a monoclonal antibody (mAb) against HA using a hapten produced by the introduction of a phenyl-containing linker. The novel mAb exhibited high sensitivity against HA as determined by ELISA, with a half-maximal inhibitory concentration of 21.51 ng/mL. A gold nanoparticle-based immunosensor was fabricated for rapid detection of HA in fish samples. After optimizing the immunosensor, a visual limit of detection (LOD) and a calculated LOD were 0.25 mg/kg and 10.48 μg/kg for HA, respectively. Recovery rates from the spiked fish samples ranged from 87.33% to 104.67% with the coefficient of variation below 10.82%. Concurrently, the whole process in testing real sample was completed within 15 min, and all results were well confirmed and comparable by liquid chromatography-mass spectrometry and the commercial test strip. These data revealed that the proposed immunosensor could be used as a monitoring tool for the rapid and direct detection of HA in fish samples.

Simultaneous immunodetection of ionophore antibiotics, salinomycin and narasin, in poultry products and milk

Rabbit polyclonal antibodies were generated against the ionophore antibiotic salinomycin (SAL) as a determinant of the BSA-SAL conjugate. The homologous ELISA format was found to be preferred for similar recognition of SAL and narasin (NAR) with IC₅₀ values of 0.55 and 0.57 ng mL^-1, respectively. Both analytes could be determined in the range of 0.1-2.7 ng mL^-1 (IC₂₀-IC₈₀) with a detection limit of 0.03 ng mL^-1. To analyze matrices, individual pretreatment of samples was required. For chicken muscles, simple buffer extraction was sufficient to recover 87-110% of ionophores. Extraction with acetonitrile followed by evaporation of the solvent was best for recovering 67-108% SAL and NAR from egg homogenate. A feature of the extraction of ionophores from milk was the elimination of fat-mediated interference by organic solvation. It was found that the absence of Na⁺ and K⁺ ions during reconstitution of sample extracts was a key factor contributing to the increase in the average recovery of ionophores from 32% to 93%. Thanks to this special pretreatment and improved recovery, the developed immunoassay method was suitable for the analysis of ionophore antibiotics SAL and NAR in a milk matrix, which has not been previously reported.

A colloidal gold immunochromatographic strip for quantitative detection of azoxystrobin in vegetables

Develop the immunochromatographic strip assay for rapid on-site screening of azoxystrobin in vegetables.

Fluorescence based immunochromatographic sensor for rapid and sensitive detection of tadalafil and comparison with a gold lateral flow immunoassay

Tadalafil (TDL) is an illegal additive drug found in drinks and functional foods that could threaten public health. There was a great concern whether the adulteration occurred in coffee added with similar type of herbs. Here we have developed a rapid, simple, sensitive, and semi-quantitative lateral flow immunoassay (LFIA) based on gold and fluorescence labelled monoclonal antibody (mAb) for detection of TDL in coffee sample. Under optimal conditions, the cut off limits using gold nanoparticles labelled mAb (GLM) was found to be 250 ng/mL and 100 ng mL using fluorescent labelled mAb (FLM) in coffee samples. The coffee samples were spiked with TDL, and the LFIA with GLM gave average recoveries of 92-105.3% (intra-assay) and 96.6-105.9% (inter-assay), meanwhile with FLM gave recoveries 97.9-107.3% (intra-assay) and 98.3-108.9% (inter-assay). Results gave LFIA with FLM more sensitive than with GLM and all the test can be completed within 10 min, which would be an option for convenient and rapid assay of TDL detection.

Rapid and Sensitive Immunochromatographic Method-Based Monoclonal Antibody for the Quantitative Detection of Metalaxyl in Tobacco

In this study, we prepared a monoclonal antibody (mAb) against metalaxyl (Met) with a half-maximum inhibitory concentration (IC₅₀) of 0.54 ng/mL based on a new hapten, and a gold nanoparticle-based immunochromatographic assay (GICA) was developed for the rapid detection of Met residues in tobacco. Under optimal conditions, even with the naked eye, one can see the semiquantitative analysis results. The naked eye detection limit of Met in tobacco is 25 μg/kg, and the detection threshold is 100 μg/kg. In addition, the cross-reactivity test shows that the mAb has good specificity for Met, and the GICA results have a good correlation with the indirect competitive enzyme-linked immunosorbent assay and liquid chromatography with tandem mass spectrometry test results, which show that the method is feasible and reliable and are more convenient and quicker than the methods using instrumentation for detection. Therefore, GICA may provide a useful tool for the rapid screening and detection of Met residues in tobacco.

Rapid detection of 21 β-lactams using an immunochromatographic assay based on the mutant BlaR-CTD protein from Bacillus Licheniformis

In this study, a gold immunochromatographic assay (GICA) based on a penicillin receptor protein (PBP) is proposed to simultaneously detect penicillin, cephalosporin, and carbapenem antibiotics in milk and chicken.