Preparation of amine-modified amphiphilic resins for the extraction of trace pharmaceuticals and personal care products in environmental waters

Insights into the performance and mechanism of a reinforced lignocellulosic sorbent fabricated from sawdust biomass for multi-tasking application in enrofloxacin removal and monitoring

Natural lignocellulose-based materials have numerous strengths such as abundance, cheap price and biodegradability, which indicates a brilliant prospect for environmental protection. This work aimed to design an efficient sorbent (NaSS-PSD) by pine sawdust (PSD) for the surveillance and management of enrofloxacin (ENR). In the study, sodium styrenesulfonate (NaSS) was chosen as an effective monomer to ameliorate the performance of PSD by graft copolymerization. The removal of ENR by NaSS-PSD was enhanced in comparison with the ungrafted ones under investigated conditions. Pseudo-second-order and Temkin were the best-fitted models to describe the adsorption behavior. For the first time, NaSS-PSD was employed as a novel extractant of solid-phase extraction (SPE) and dispersive solid-phase microextraction (DSPME) to develop accurate, eco-friendly and economic analytical techniques for trace ENR determination. Good linearity and reproducibility were obtained. The limits of detection were 0.41 μg/L for DSPME-HPLC-DAD technique and 0.15 μg/L for SPE-HPLC-DAD technique. These two methods exhibited satisfying practicability when applied to quantify ENR residue in real waters. The study on interfacial interaction mechanism and preferential binding sites suggested that hydrogen bond and π-π interactions took the primary responsibility. Our work provides a good perspective for tailoring natural lignocellulosic biomass to be alternative adsorbents for emerging pollutants.

Microwave-assisted esterification and electro-enhanced solid-phase microextraction of omega-3 polyunsaturated fatty acids in eggs

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), a type of fatty acid that has many health benefits, are of increasing concern. Herein, we developed a method for the rapid esterification and enrichment of ω-3 PUFAs in eggs, which includes microwave-assisted esterification (MAE) and electrically enhanced solid-phase microextraction (EE-SPME). Combined with gas chromatographic, efficient detection of ω-3 PUFAs was achieved in eggs. Under microwave radiation, the esterification efficiency exhibited a significant increase ranging from 5.06 to 10.65 times. The EE-SPME method reduced extraction time from 50 to 15 min. In addition, improvements in extractive fiber coating materials were explored, which ensured efficient extraction of ω-3 PUFAs. Under the optimal conditions, the method displayed a low detection limit (1.01-1.54 μg L-1), good recoveries (85.82%-106.01%), and wide linear range (7.5-1000 μg L-1), which was successfully applied to determine ω-3 PUFAs in real egg samples.