Ultrasensitive "Hunter of Target": Rabbit Monoclonal Antibody-Based Competitive Lateral Flow Immunoassay for Saxitoxin.

The rapid, sensitive, and accurate detection of paralytic shellfish toxins (PSTs), such as saxitoxin (STX), is critical for protecting human health due to the frequent occurrence of toxic red tides. In this work, to address the low affinity of traditional mouse monoclonal antibodies (m-mAbs), rabbit monoclonal antibodies (r-mAbs) against STX were produced by a single B-cell sorting culture and a cross-selection strategy. The r-mAbs showed 100-fold improvement in sensitivity (IC = 0.

Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry-Based Metabolic Characterization of Mango Ripened by Different Methods.

So far, the metabolic differences between tree-ripened and postharvest-ripened mangoes have largely remained unexplored. The aim of this study was to evaluate the chemical composition of nutrient substances in mangoes subjected to different ripening methods. An untargeted metabolomic approach based on ultra performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was carried out to investigate the differences between artificially ripened and naturally ripened mangoes.

Nanoflower Microreactor Based Versatile Enhancer for Recognition Cofactor-Dependent Enzyme Biocatalysis toward Saxitoxin Detection.

Investigating organic carriers' utilization efficiency and bioactivity within organic-inorganic hybrid nanoflowers is critical to constructing sensitive immunosensors. Nevertheless, the sensitivity of immunosensors is interactively regulated by different classes of biomolecules such as antibodies and enzymes. In this work, we introduced a new alkaline phosphatase-antibody-CaHPO hybrid nanoflowers (AAHNFs) microreactor based colorimetric immunoprobe.

Microbial contribution to 14 biogenic amines accumulation in refrigerated raw and deep-fried hairtails (Trichiurus lepturus).

Biogenic amines (BAs) produced by microbial decarboxylation of amino acids are crucial toxic nitrogenous compounds in fish. An optimized ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method with simple pretreatment was established to detect 14 BAs in both raw (control check, CK) and deep-fried (DF) hairtails. This method exhibited a good linear relationship with average recoveries of 73.

High-throughput detection and dietary exposure risk assessment of 44 mycotoxins in Mango, Litchi, Longan, and their products in South China.

Mycotoxins exposure from food can trigger serious health hazards. This study aimed to establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous detection of 44 mycotoxins in fruits and their products, followed by dietary exposure risk assessment. The optimized UPLC-MS/MS method exhibited a good linear relationship with correlation coefficients ≥ 0.

A Chemiluminescence Enzyme Immunoassay Based on Biotinylated Nanobody and Streptavidin Amplification for Diazinon Sensitive Quantification.

The advantages of genetic modification and preferable physicochemical qualities make nanobody (Nb) easy to develop a sensitive and stable immunosensor platform. Herein, an indirect competitive chemiluminescence enzyme immunoassay (ic-CLEIA) based on biotinylated Nb was established for the quantification of diazinon (DAZ). The anti-DAZ Nb, named Nb-EQ1, with good sensitivity and specificity, was obtained from an immunized library via a phage display technique, where the molecular docking results indicated that the hydrogen bond and hydrophobic interactions between DAZ and complementarity-determining region 3 and framework region 2 in Nb-EQ1 played a critical role in the Nb-DAZ affinity processes.

Preparation and evaluation of a novel chlorine dioxide preservative based on citric acid grafted carboxymethyl chitosan.

Instrument-free chlorine dioxide (ClO) preservative for fruit and vegetable has gained great attention due to its convenience and safety. In this study, a series of carboxymethyl chitosan (CMC) with citric acid (CA) substituents were synthesized, characterized, and further used to prepare a novel ClO slow-releasing preservative for longan. UV-Vis and FT-IR spectra revealed that CMC-CA#1-3 were successfully prepared.

Comparative nutritional and metabolic analysis reveals the taste variations during yellow rambutan fruit maturation.

The metabolic reasons for rambutan taste variations during maturity are unknown. Here, we obtained a unique rambutan cultivar Baoyan No.2 (BY2) with a strong yellow pericarp and excellent taste, the sugar-acid ratios of which ranged from 21.

Metabolic Profiling and Potential Taste Biomarkers of Two Rambutans during Maturation.

The metabolite-caused taste variation during rambutan maturation is unknown due to a lack of systematic investigation of all components. In this study, three growing stages, including unripe (S1), half-ripe (S2), and full-ripe (S3) BY2 and BY7 rambutans were compared and profiled by UPLC-MS/MS-based widely targeted metabolomics analysis. We demonstrated that the sugar-acid ratios of two rambutans were greatly improved between the S2 and S3 stages.

Risk Assessment of Triflumezopyrim and Imidacloprid in Rice through an Evaluation of Residual Data.

Triflumezopyrim, a novel mesoionic insecticide used to control planthoppers, is a potential substitute for imidacloprid. In this study, triflumezopyrim and imidacloprid residues in rice were determined using a quick, easy, cheap, effective, rugged, and safe procedure combined with ultra-high-performance liquid chromatography-tandem mass spectrometry. The limit of quantification of both triflumezopyrim and imidacloprid was 0.

Detection and Degradation Characterization of 16 Quinolones in Soybean Sprouts by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry.

Recently, there have been increasing safety concerns about the illegal abuse of quinolone in soybean sprouts. This study aimed to establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous detection of 16 quinolones (QNs) in soybean sprouts, and then reveal their degradation characteristics. The samples were extracted with acetonitrile (with 1% formic acid), purified by a C18 adsorbent, and separated by an ACQUITY UPLC BEH C18 (1.

Comparative Metabolomics Analysis Reveals the Taste Variations among Three Selected Wampee Cultivars.

Sugars and acids of wampee predominantly influence consumer taste preference and its commercial value. The molecular basis of taste variations is currently unknown due to the lack of a large-scale investigation of metabolites in wampee. Here, three tastes cultivars, including YF1 (sweet), YF2 (sweet-sour) and YF3 (sour) wampees with sugar-acid ratios ranging from 1.

Identification and verification of key taste components in wampee using widely targeted metabolomics.

Due to the lack of comprehensive evaluation of all metabolites in wampee, the metabolic reasons for taste differences are unclear. Here, two local varieties YF1 (sweet taste) and YF2 (sweet-sour taste), were selected for quality analysis, followed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) based widely targeted metabolomic analysis. YF1 and YF2 were clearly separated by principal component analysis (PCA) and cluster analysis, and 449 metabolites were different between the cultivars, including 29 carbohydrates and 29 organic acids.

Analysis on quality differences associated with metabolomics of rambutan during different temperature storage.

This study aimed to understand how temperatures differentially impact the crucial quality indices and metabolites in rambutan during storage. Rambutan browned quickly at room temperature from 0 d (control). After ten days at 5 ℃, browning index and lightness were 4.