Preparation of magnetic mesoporous metal-phenolic coordination spheres for extraction of crystal violet and leuco-metabolites in fish

Recent advance on microextraction sampling technologies for bioanalysis

The contents of target substances in biological samples are usually at low concentration levels, and the matrix of biological samples is usually complex. Sample preparation is considered a very critical step in bioanalysis. At present, the utilization of microextraction sampling technology has gained considerable prevalence in the realm of biological analysis. The key developments in this field focus on the efficient microextraction media and the miniaturization and automation of adaptable sample preparation methods currently. In this review, the recent progress on the microextraction sampling technologies for bioanalysis has been introduced from point of view of the preparation of microextraction media and the microextraction sampling strategies. The advance on the microextraction media was reviewed in detail, mainly including the aptamer-functionalized materials, molecularly imprinted polymers, carbon-based materials, metal-organic frameworks, covalent organic frameworks, etc. The advance on the microextraction sampling technologies was summarized mainly based on in-vivo sampling, in-vitro sampling and microdialysis technologies. Moreover, the current challenges and perspective on the future trends of microextraction sampling technologies for bioanalysis were briefly discussed.

Ant nest-like hierarchical porous imprinted resin-dispersive solid-phase extraction for selective extraction and determination of polychlorinated biphenyls in milk

Polychlorinated biphenyls (PCBs) are persistent toxic, organic chemicals that tend to accumulate in the food chain. This study reports the rapid and selective extraction and determination of PCBs (PCB81, 153, 105, 126, and 157) in milk samples by a dispersive solid-phase extraction (DSPE) coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). An ionic liquid-molecularly imprinted porous resin (IL-MIPPR) as a DSPE adsorbent was synthesized from m-aminophenol, formaldehyde, and 2,2'-benzidinedisulfonic acid as the monomer, crosslinker, and virtual template, respectively. The IL-MIPPR had a fast mass transfer (1.0 min) and good selectivity (imprinting factors of 1.8-3.0). The IL-MIPPR - DSPE - GC-MS/MS method exhibited good linearity (R² ≥ 0.9995), the limit of detections (LODs) < 0.6 pg/g, and the recoveries ranged from 82.8 % to 106 % with relative standard deviations ≤ 6.6 %. This method is thus better than previously reported methods in terms of the LOD, the adsorbent dosage, and the extraction time.

Preparation of tannic acid and L-cysteine functionalized magnetic composites for synergistic enrichment of N-glycopeptides followed by mass spectrometric analysis

Glycoprotein is involved in a variety of biological activities and has been linked to a number of diseases. Glycopeptide enrichment prior to mass spectrometry (MS) detection is crucial to reduce interference, improve detection efficiency, and analyze proteomics deeply and comprehensively. Here, we prepared a novel magnetic hydrophilic material combining tannic acid (TA) and L-cysteine (L-Cys) through a simple and fast procedure. Owing to the synergistic hydrophilic interaction of TA and L-Cys, the obtained adsorbent material shows excellent enrichment performance toward N-glycopeptides with low detection limit, high selectivity, and good reusability. Besides, the material can also be utilized for the enrichment of N-glycopeptides in human serum and saliva, which shows its application prospect in complex biological samples.

Ultrasonic role to activate persulfate/chlorite with foamed zero-valent-iron: Sonochemical applications and induced mechanisms

The novel system, consisting of composite oxidants (persulfate/chlorite, S2O82-/ClO2-) and stationary phase activator (zero-valent-iron foam, Fe0f) driven by ultrasonic (US) field, was applied to treat the triphenylmethane derivative effectively even at low temperature (≈ 289 K). By comparisons of sub-systems, the US roles to S2O82-, ClO2-, and Fe0f were seriatim analyzed. US made the reaction order of multi-component system tend to within 1 (leading to de-order reaction), and widened pH activating range of the Fe0f by sonicate-polishing during the process of ClO2- co-activating S2O82-. US and Fe0f were affected by fluid eddy on activating S2O82-/ClO2-. The Fe0f had slight effect on the temperature of US bubble-water interface but the addition of ClO2- lowered it. The partitioning capacity of the above US reactive zone increased during the reaction. US and ClO2- could enrich the kinds of degradation intermediates. The contributions of free radicals (ClOx-based radicals, sulfate radicals (SO4-), and hydroxyl radicals (OH)) and non-free radicals (ClO2, and O = FeIV/V from ionic Fe under "-O-O-" of S2O82- and cyclic adjustment reaction of ClO2-) processes by sonochemical induction were equally important by corresponding detection means. Especially, real-time and online high-resolution mass spectrum by self-developing further confirmed the chain transfers of different free radicals due to US role. The findings expanded the application of sono-persulfate-based systems and improved understanding on activation mechanism.