Monoclonal antibody based colloidal gold immunochromatographic assay for the visual and rapid screening of profenofos.

Profenofos (PFF) is a commonly used organophosphorus insecticide that requires strict monitoring due to its potential environmental, ecological, and human health risks originating from residues in soil and water systems, as well as accumulation in crops. In this study, a novel monoclonal antibody (mAb) specific to PFF was prepared for the first time and the recognition mechanism was investigated through molecular simulation. Subsequently, a mAb-based colloidal gold immunochromatographic assay (GICA) was developed for the rapid screening of PFF in fruit and vegetable samples. The mAb exhibited an IC50 value of 12.9 ng/mL, and limit of detection (LOD) of 4.6 ng/mL, respectively in indirect competitive immunosorbent enzyme-linked immunosorbent assay (ic-ELISA). After optimization, the developed GICA exhibited a visual limit of detection (vLOD) of 20 ng/mL and a quantitative of detection (qLOD) of 5.2 ng/mL, with a linear range from 10.0 to 83.8 ng/mL. Good correlation was observed between the results of GICA and standard Gas Chromatography-Tandem Mass Spectrometry (GC-MS/MS) in matrix and recovery test. The developed GICA can be used for rapid sample detection within 15 min, which is an excellent tool for screening PFF in foods and environmental samples.

Natural products and extracts from plants as natural UV filters for sunscreens: A review.

Although solar exposure is necessary for human health, phototoxicology induced by excessive UVB and UVA radiation, which involves sunburns, skin aging and even tumorigenesis, has been widely researched. Sunscreen is one of the most important ways to protect skin from UV phototoxic damage. As well as inorganic and organic UV filters, some natural products or plant extracts with aromatic rings in their structures, such as flavonoids or polyphenols, can absorb UV to reduce sunburn, acting as a natural UV filter; they also show antioxidant or/and anti-inflammatory activity. This could explain why, although there are no officially approval natural commercial sun-filters, more and more commercial sunscreen products containing plant extracts are available on the market. Here we summarize articles focusing on natural UV filters from plant published in the last 6 years, selecting the most significant data in order to better understand the photoprotective activity of natural products and extracts from plants, including their major constituents and main biological effects, methods for evaluating UV radiation resistance, anti-UV radiation experimental models and anti-UV radiation mechanisms.

Simultaneous determination of 9-dehydro-17-hydro-andrographolide and sodium 9-dehydro-17-hydro-andrographolide-19-yl sulfate in rat plasma by UHPLC-ESI-MS/MS after administration of xiyanping injection: application to a pharmacokinetic study.

9-Dehydro-17-hydro-andrographolide (DHA) and sodium 9-dehydro-17-hydro-andrographolide-19-yl sulfate (DHAS) are active ingredients of xiyanping injection in clinical use. A simple, rapid and sensitive UHPLC-ESI-MS/MS method was developed for the determination of DHA and DHAS in rat plasma, and the pharmacokinetics of DHA and DHAS after intravenous administration of xiyanping injection was investigated. The plasma samples were treated with methanol to precipitate out protein, and the separation of DHA and DHAS was achieved on a Waters BEH C18 column with a mobile phase consisting of acetonitrile and 10 mmol/L ammonium acetate solution at a flow rate of 0.4 mL/min. DHA, DHAS and the internal standard (internal standard, IS) diethylstilbestrol were detected at negative ion mode. The precursor-product ion pairs used in multiple reaction monitoring mode were: m/z 349.1 → 286.9 (DHA), m/z 428.9 → 96.0 (DHAS) and m/z 267.1 → 236.9 (IS). Calibration curves offered satisfactory linearity within the test range, and all correlation coefficients were >0.995. The lower limit of detection of DHA and DHAS in plasma samples were determined to be 0.1 ng/mL. The lower limit of quantitation was 0.5 ng/mL for DHA and DHAS. All the recoveries of the quality control samples were in the range of 86.0-102.4%. The ratios of matrix effect were between 89.2 and 105.1%. The method was fully validated and successfully applied to the pharmacokinetic study of DHA and DHAS in rats. The study showed that both DHA and DHAS were distributed and eliminated rapidly in rats.