Simple determination of dichlorvos in cases of fatal intoxication by gas Chromatography-Mass spectrometry

Therapeutic potential of 2S-hesperidin against the hepatotoxic effects of dichlorvos in rats

Dichlorvos (DDVP) is an organophosphate insecticide that enhances food production and repels disease vectors. However, it provokes cytotoxicity. 2S-hesperidin (2S-HES) is a potent antioxidant, anti-inflammatory, and anti-lipidemic flavanone. Regardless, the 2S-HES impact on DDVP-occupied hepatic injury remains fuzzy. We evaluated the therapeutic potential of 2S-HES in a rat model of DDVP-elicited hepatic intoxication. Forty-two rats were randomly allotted to seven groups (n = 6/condition): control, DDVP (8 mg kg⁻1day⁻1), DDVP with 2S-HES (50 and 100 mg kg⁻1day⁻1), DDVP with atropine, and 2S-HES alone (50 and 100 mg kg⁻1day⁻1). DDVP was administered orally for 7 days, followed by 14 days of 2S-HES chemotherapy. 2S-HES intervention partially mitigated DDVP-triggered alterations in leakage enzymes (ALT, AST, ALP, LDH-5), total protein, albumin, globulin, bilirubin, electrolytes, ion-transporters, lipid profiles, and HMG-CoA reductase. Furthermore, 2S-HES partially reversed DDVP-provoked increases in hepatic H₂O₂, NO, and malondialdehyde; transposed DDVP-mediated decreased liver GSH amount and activities of GST, SOD, catalase, and GPx; attenuated DDVP-triggered upregulated NF-κB-p65 and caspase-3; and abated DDVP-engendered repressed interleukin-10 mRNA expression. Cytoarchitectural analyses authenticated the 2-HES reduction in DDVP-evoked hepatocellular vacuolation. Altogether, 2S-HES elicited promising alternative or adjunctive therapy for partially mitigating DDVP-incited hepatic injury by attenuating leakage enzymes, ionoregulatory disruptions, ion pump inhibition, dyslipidemias, oxidative stress, inflammation, and apoptosis.

Oral Administration of Lactiplantibacillus plantarum CCFM8661 Alleviates Dichlorvos-Induced Toxicity in Mice

Dichlorvos (DDVP) is an organophosphorus pesticide commonly used in agriculture for pest control, which may enter the organism from the food chain and cause harm. This study aimed to investigate the mitigation effect of Lactiplantibacillus plantarum CCFM8661 (a strain of the bacteria) on DDVP toxicity. Sixty male mice were randomly divided into five groups including control (saline), model (DDVP), low-dose, medium-dose, and high-dose groups, and alleviating effect was evaluated by determining body weight, pesticide residues, oxidative stress, and inflammation, and by histological analysis. The results showed that compared with the model group, body weight and acetylcholinesterase activity, and SOD, CAT, T-AOC, and GSH levels significantly increased, and serum DDVP content, MDA level, IL-1β, and TNF-α significantly decreased after administration of the L. plantarum CCFM8661. The study demonstrated that L. plantarum CCFM8661 exhibited a significant detoxification effect on pesticide toxicity in mice, providing a theoretical basis for the application of probiotics in mitigating pesticide-induced damage.

Nanoextraction from a flow of a highly diluted solution for much-improved sensitivity in offline chemical detection and quantification

Preconcentration of the target compound is a critical step that ensures the accuracy of the subsequent chemical analysis. In this work, we present a straightforward yet effective liquid-liquid extraction approach based on surface nanodroplets (i.e., nanoextraction) for offline analysis of highly diluted sample solutions. The extraction and sample collection were streamlined in a 3-m microcapillary tube. The concentration of the target analyte in surface nanodroplets was significantly increased compared to the concentration in the sample solution, reaching several orders of magnitude. A limit of detection (LOD) was decreased by a factor of ∼10³ for an organic model compound in Fourier-transform infrared spectroscopy (FTIR) measurements and ∼10⁵ for a model fluorescent dye in fluorescence detection. The quantitative analysis of the organic compound was also achieved in a wide concentration region from 10^-3 M to 10^-4 M. The total volume of surface nanodroplets can be manipulated to further enhance extraction efficiency, according to the principle that governs droplet formation by solvent exchange. Additionally, our method exhibited significantly improved sensitivity compared to traditional dispersive liquid-liquid microextraction (DLLME). The LOD of the fluorescent dye and the organic model compound obtained with DLLME was 3 orders of magnitude and 20 times higher than the LOD achieved through nanoextraction approach. The nanoextraction developed in this work can be applied to preconcentrate multi-compounds from river water samples, without clear interference from each other. This can further extend its applicability for the detection and quantification of target analytes in complex aqueous samples by common analytical instruments.

Fabric phase sorptive extraction-gas chromatography-mass spectrometry for the determination of favipiravir in biological and forensic samples

Favipiravir, a pyrazine analog, is proposed as providential antiviral agent against the COVID-19 infection during 2020 pandemic emergency. For the first time, a fabric phase sorptive extraction (FPSE) combined with gas chromatography-mass spectrometry (GC-MS) has been developed and applied for the determination of favipiravir (FAV) in biological samples (human plasma, blood and urine), pharmaceutical and forensic samples. The method comprises of extraction of FAV by FPSE followed by its derivatization with N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) and GC-MS analysis. Design of experiment-based optimization was performed using Placket-Burman Design (PBD) and Central Composite Design (CCD) for the screening of significant factors of FPSE and their optimization, respectively. Among all tested membranes, sol-gel polyethylene glycol (PEG) has offered the best extraction efficiency for FAV. Under optimum conditions, the proposed method was found to be linear in the range of 0.01–10 µg mL⁻¹ by GC-MS. The LODs and LOQs were as low as 0.001-0.0026 μg mL⁻¹ and 0.003-0.0086 μg mL⁻¹, respectively by GC-MS. Intra-day and inter-day precisions were less than 5 and 10 %, respectively, showing good method precision. The proposed method has been successfully applied to detect and quantify FAV in human urine, whole blood and plasma samples along with seized forensic samples. In addition, the proposed method has been evaluated for its green character by ComplexGAPI index.

Methods and Advances in the Design, Testing and Development of In Vitro Diagnostic Instruments

With the continuous improvement of medical testing and instrumentation engineering technologies, the design, testing and development methods of in vitro diagnostic instruments are developing rapidly. In vitro diagnostic instruments are also gradually developing into a class of typical high-end medical equipment. The design of in vitro diagnostic instruments involves a variety of medical diagnostic methods and biochemical, physical and other related technologies, and its development process involves complex system engineering. This paper systematically organizes and summarizes the design, testing and development methods of in vitro diagnostic instruments and their development in recent years, focusing on summarizing the related technologies and core aspects of the R&D process, and analyzes the development trend of the in vitro diagnostic instrument market.

A Non-Instrumental Green Analytical Method Based on Surfactant-Assisted Dispersive Liquid-Liquid Microextraction-Thin-Layer Chromatography-Smartphone-Based Digital Image Colorimetry(SA-DLLME-TLC-SDIC) for Determining Favipiravir in Biological Samples

Favipiravir (FAV) has become a promising antiviral agent for the treatment of COVID-19. Herein, a green, fast, high-sample-throughput, non-instrumental, and affordable analytical method is proposed based on surfactant-assisted dispersive liquid-liquid microextraction (SA-DLLME) combined with thin-layer chromatography-digital image colourimetry (TLC-DIC) for determining favipiravir in biological and pharmaceutical samples. Triton X-100 and dichloromethane (DCM) were used as the disperser and extraction solvents, respectively. The extract obtained after DLLME procedure was spotted on a TLC plate and allowed to develop with a mobile phase of chloroform:methanol (8:2, v/v). The developed plate was photographed using a smartphone under UV irradiation at 254 nm. The quantification of FAV was performed by analysing the digital images' spots with open-source ImageJ software. Multivariate optimisation using Plackett-Burman design (PBD) and central composite design (CCD) was performed for the screening and optimisation of significant factors. Under the optimised conditions, the method was found to be linear, ranging from 5 to 100 µg/spot, with a correlation coefficient (R2) ranging from 0.991 to 0.994. The limit of detection (LOD) and limit of quantification (LOQ) were in the ranges of 1.2-1.5 µg/spot and 3.96-4.29 µg/spot, respectively. The developed approach was successfully applied for the determination of FAV in biological (i.e., human urine and plasma) and pharmaceutical samples. The results obtained using the proposed methodology were compared to those obtained using HPLC-UV analysis and found to be in close agreement with one another. Additionally, the green character of the developed method with previously reported protocols was evaluated using the ComplexGAPI, AGREE, and Eco-Scale greenness assessment tools. The proposed method is green in nature and does not require any sophisticated high-end analytical instruments, and it can therefore be routinely applied for the analysis of FAV in various resource-limited laboratories during the COVID-19 pandemic.