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A portable mass spectrometer (PMS) was combined with a mesoporous silica material (SBA-15) coated solid-phase microextraction (SPME) Arrow to develop a rapid, easy-to-operate and sensitive method for detecting five veterinary drugs—amantadine, thiabendazole, sulfamethazine, clenbuterol, and ractopamine—in milk and chicken samples. Equipped with a pulsed direct current electrospray ionization source and a hyperboloid linear ion trap, the PMS can simultaneously detect all five analytes in approximately 30 s using a one-microliter sample. Unlike traditional large-scale instruments, this method shows great potential for on-site detection with no need for chromatographic pre-separation and minimal sample preparation. The SBA-15-SPME Arrow, fabricated via electrospinning, demonstrated superior extraction efficiency compared to commercially available SPME Arrows. Optimization of the coating preparation conditions and SPME procedures was conducted to enhance the extraction efficiency of the SBA-15-SPME Arrow. The extraction and desorption processes were optimized to require only 15 and 30 min, respectively. The SBA-15-SPME Arrow–PMS method showed high precision and sensitivity, with detection limits and quantitation limits of 2.8–9.3 µg kg−1 and 10–28 µg kg−1, respectively, in milk. The LOD and LOQ ranged from 3.5 to 11.7 µg kg−1 and 12 to 35 µg kg−1, respectively, in chicken. The method sensitivity meets the requirements of domestic and international regulations. This method was successfully applied to detect the five analytes in milk and chicken samples, with recoveries ranging from 85% to 116%. This approach represents a significant advancement in food safety by facilitating rapid, in-field monitoring of veterinary drug residues. [ABSTRACT FROM AUTHOR]

In nature, efficient and selective ion transport is facilitated by ion‐conductive channels in cell membranes; these channels reveal an architectural design with specialized functionality. Drawing inspiration from this, mechanistic insights into the angstrom‐scale‐channel membrane composed of ionic‐crosslinked polybenzimidazole and sulfonated poly(ether ether ketone), exhibiting functional differentiation and efficient ion‐sieving properties are presented. Nanochannels allow for strong hydrogen‐bonding interactions with hydrated ions of higher polarity, while rendering significant electrostatic charge effects that impede the transition of multivalent ions by compressing effective passageways. Both hydrogen bonding and electrostatic interactions synergistically result in high selectivity for monovalent ions over multivalent ions because the latter requires overcoming higher energy barriers for transport compared with the former, thereby causing varying extents of ion dehydration within the nanochannels. The resulting membrane achieves a high monovalent ion permeation rate of 1.35 mol m−2 h−1 with a high mono/multivalent ion selectivity of 56.5 for K+/Mg2+ and 286 for K+/Al3+. [ABSTRACT FROM AUTHOR]

Specific and rapid detection of live Staphylococcus aureus (S.A) in environmental and food samples is critically important for protecting human health. In order to fulfill this purpose, two kinds of novel egg yolk antibody (IgY) immobilized immunomagnetic beads (IMBs; mSiO2-IgY and mMOF-IgY), with core–shell mSiO2 and mMOF as substrate, were prepared for selectively enriching S.A from samples. Furthermore, the IMBs with captured S.A were collected and re-dissolved in 0.5 mL PBS. After that, a cotton swab coated with sodium dodecylsulfate (SDS) was put in the solution to lyse S.A cells and emit ATP bioluminescence of the luciferin/luciferase system. Finally, a portable bioluminescence detector was used for quantification of ATP corresponding to S.A concentration. The results demonstrated that mMOF-IgY can enrich more S.A than mSiO2-IgY and emit a stronger signal. The reasons may be due to the higher immobilization amount of IgY on the IMBs. Under optimal conditions, the calibration line of S.A concentration was 10–105 CFU mL−1 by mMOF-IgY within 30 min. The low detection limit of S.A was 3 CFU mL−1. The results demonstrated that the assay takes much shorter time than plate counting. Its portability and excellent detection capability are suitable for rapid monitoring of specific pathogens in foods. [ABSTRACT FROM AUTHOR]

Ion-selective membranes (ISM) with sub-nanosized pore channels hold significant potential for applications in saline wastewater treatment and resource recovery. Herein, novel synergistic ion channels featuring bi-periodic structures were constructed through the coordination of functional Cyclen (quaternary_1,4,7,10-tetraazacyclododecane, Q_Cyclen) and Cu 2+ -m-Phenylenediamine (Cu 2+ -MPD) to develop supramolecular membranes for lithium extraction. The exterior quaternary ammonium-rich sites exhibit a significant Donnan exclusion effect, resulting in tremendous mono/divalent (Li + /Mg 2+ ) ion selectivity; while the interior regular-confined channels of Cyclen yield a fast vehicular pathway, facilitating water molecules and Li + ion-selective transport. The optimized membrane exhibited an increased water permeance of 19.2 L·m -2 ·h -1 ·bar -1 and simultaneously promoted Li + /Mg 2+ selectivity (achieving a selectivity of 18.5 under a Mg 2+ /Li + mass ratio of 30), surpassing the trade-off limit of conventional nanofiltration membranes. Due to the acquired excellent Li + /Mg 2+ selectivity, lithium extraction from simulated salt-lake brines was successfully achieved through a two-stage nanofiltration process, reducing the Mg 2+ /Li + mass ratio from 40 to 1.1. This work validates the applicability of macrocyclic with intrinsic sub-nanosized channels and desired multifunctionality for developing high-performance ISM for efficient lithium separation and beyond., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Introduction: Fruit color significantly influences the quality of horticultural crops, which affects phytochemical diversity and consumer preferences. Despite its importance, the genetic basis of the white-colored fruit in tomatoes remains poorly understood., Methods: In this study, we demonstrate that white-fleshed tomato varieties accumulate fewer carotenoids than yellow-fleshed varieties. We developed various segregating populations by hybridizing red, yellow, and white fruit tomato cultivars., Results: Genetic analysis revealed that the white fruit color trait is controlled by a single gene that dominates both red and yellow fruits. Bulk segregant RNA sequencing provided a preliminary map of a 3.17 Mb region on chromosome 3 associated with the white color trait. Based on kompetitive allele-specific PCR (KASP) markers, we narrowed the candidate gene region to 819 kb. Within this region, we identified a 4906-bp sequence absence variation near Phytoene Synthase 1 (SlPSY1) specific to white-colored tomatoes. Genotyping of the progeny and natural populations using a single nucleotide polymorphism adjacent to this absence of variation confirmed its key role in white fruit formation., Discussion: Collectively, our findings provide insights into white fruit trait formation in tomatoes, enabling tomato breeders to precisely introduce white fruit traits for commercial exploitation., Competing Interests: Authors JL, XF, FY, CZ, PF, NW, QS, NG, XW, NL were employed by Weimeng Seed Co. Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Fang, Yu, Zhang, Fan, Wang, Shao, Gan, Lv, Ouyang, Zhang, Wu and Liao.)