RESUMEN
A simple and effective ultrasound-assisted dispersive micro solid-phase extraction (UA-dµSPE) method was developed for the spectrophotometric determination of traces maneb in food and water. In this study, a new hybrid block copolymer poly (vinyl benzyl chloride-b-dimethyl aminoethyl methacrylate) (Pvb-DMA) was synthesized and characterized using techniques such as FTIR, SEM-EDX. The synthesized Pvb-DMA was used as an adsorbent for the extraction of maneb for first time in this study. The effects of different experimental variables such as pH, adsorbent amount, sample volume, eluent type were optimized. The statistical toll factorial design was applied to estimate the individual and combined impact of parameters on the extraction of maneb. The applicability of different solvents such as acetone, methanol, ethanol, tetrahydrofuran, acetonitrile for maneb recovery from adsorbent was tested. The detection and quantification limits were found to be 3.3 ng mL-1 and 10.0 ng mL-1, respectively. In addition, the preconcentration factor and linear range was obtained 300 and 10-500 ng mL-1. The extraction recovery and relative standard deviation were found to be 95 % and 2.8 %, respectively.
RESUMEN
Botulinum toxin A(BoNT/A) is a neurotoxin produced by the bacteria Clostridium botulinum, which can cause serious food poisoning and is recognized as a potential biological warfare agent. BoNT/A is does not degrade easily and can remain in the complex matrix for a long time. Meanwhile, the poisonous dose of botulinum toxin exceptionally low and intravenous human lethal doses estimated at 1-3 ng/kg. Therefore, sensitive and accurate detection methods suitable for testing a wide range of complex samples are urgently needed. To this end, the "amplified luminescent proximity homogeneous assay linked immunosorbent assay" (AlphaLISA) was established for the detection of BoNT/A and its detection efficacy in plasma, beverage, food, and other complex samples was evaluated. The results showed that this method can very effectively resist matrix interference. The detection time is rapid, reaching a detection limit for all samples of up to 0.1 ng/mL in only 30 min. BoNT/A can also be accurately detected in vomit samples of patients with clinical food poisoning. This study demonstrates that AlphaLISA is an effective tool for the detection of BoNT/A in complex samples and can potentially be developed for commercial use in the future.