Application of Solid Sampling for the Determination of Total Fluorine in Fish and Seafood by High-Resolution Continuum Source Graphite Furnace Molecular Absorption Spectrometry

A simple, low cost and fast sample preparation method for fluorine determination by ISE in leguminous seeds and oilseeds

This work presents the first report of the application of microwave-induced combustion in disposable vessels (MIC-DV) as a simple and fast sample preparation step for fluoride determination by ion-selective electrode (ISE) in leguminous seeds and oilseeds samples. Several experimental conditions of MIC-DV were evaluated, such as sample mass, absorbing solution, volume of combustion igniter, purging time with oxygen, and the use of successive combustion cycles. The accuracy of MIC-DV/ISE method was evaluated by comparing the results obtained by microwave-induced combustion and determination by ion chromatography, with agreements ranged from 94 to 106%. The method allowed to achieve relatively low limits of quantification (8.3 to 16 µg g-1) comparing to AOAC method (40 µg g-1), besides the use of small amounts of reagents, less handling of digests, making the method greener and with portable features comparing to other methods.

Nano-enabled sensing of per-/poly-fluoroalkyl substances (PFAS) from aqueous systems - A review

Per-/poly-fluoroalkyl substances (PFAS) are an emerging class of environmental contaminants used as an additive across various commodity and fire-retardant products, for their unique thermo-chemical stability, and to alter their surface properties towards selective liquid repellence. These properties also make PFAS highly persistent and mobile across various environmental compartments, leading to bioaccumulation, and causing acute ecotoxicity at all trophic levels particularly to human populations, thus increasing the need for monitoring at their repositories or usage sites. In this review, current nano-enabled methods towards PFAS sensing and its monitoring in wastewater are critically discussed and benchmarked against conventional detection methods. The discussion correlates the materials' properties to the sensitivity, responsiveness, and reproducibility of the sensing performance for nano-enabled sensors in currently explored electrochemical, spectrophotometric, colorimetric, optical, fluorometric, and biochemical with limits of detection of 1.02 × 10^-6 μg/L, 2.8 μg/L, 1 μg/L, 0.13 μg/L, 6.0 × 10^-5 μg/L, and 4.141 × 10^-7 μg/L respectively. The cost-effectiveness of sensing platforms plays an important role in the on-site analysis success and upscalability of nano-enabled sensors. Environmental monitoring of PFAS is a step closer to PFAS remediation. Electrochemical and biosensing methods have proven to be the most reliable tools for future PFAS sensing endeavors with very promising detection limits in an aqueous matrix, short detection times, and ease of fabrication.