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Plant-derived exosome-like nanovesicles (ELNs) are nano-sized vesicles extracted from edible plants. Lycium ruthenicum Murray (LRM) has been gaining increasing attention due to its nutritional and medicinal value, but the ELNs in LRM has not been reported. In this study, LRM-ELNs were obtained, and the proteins, lipids, microRNAs (miRNAs) and active components in LRM tissues and LRM-ELNs was analyzed by LC-MS/MS, LC-MS, high-throughput sequencing techniques, and physical and chemical analysis. LRM-ELNs can be uptaken by PC12 cells through macropinocytosis and caveolin-mediated endocytosis primarily. Transcriptomic and western blot experiments indicate that LRM-ELNs can inhibit Aβ-induced apoptosis in PC12 cells through the MAPK and PI3K/AKT signaling pathways, with miRNAs playing a crucial role. These results indicate that LRM-ELNs have the protection effect on PC12 cells and can be considered as dietary supplements for alleviating neurodegenerative diseases., Competing Interests: Declaration of competing interest The authors confirm that they have no conflicts of interest with respect to the work described in this manuscript., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Selective and sensitive detection of microcystin-LR (MC-LR) is of vital importance because of its high toxicity and broad distribution. Herein, a novel and versatile fluorescence sensor (Cas14-pMOFs fluorescence sensor) was developed by combining the CRISPR/Cas14a system with a 2D porphyrin metal-organic framework nanosheets (2D-pMOFs) for MC-LR determination. The designed CRISPR/Cas14a system was activated by the unbound complementary DNA (cDNA), which was positively correlated with MC-LR concentration. Furthermore, the activated Cas14a protein was utilized to indiscriminately cleave the FAM-labeled single-stranded DNA (ssDNA-FAM), which was pre-absorbed on Cu-TCPP(Fe) nanosheets. Because of the desorption of the cleaved ssDNA-FAM, the pre-quenched fluorescence signal was recovered. Owing to the excellent performance in quantifying cDNA using this Cas14-pMOFs fluorescence sensor with a limit of detection (LOD) of 0.12 nM, this Cas14-pMOFs fluorescence sensor was able to detect MC-LR in a range from 50 pg/mL to 1 μg/mL with the LOD of 19 pg/mL. This work not only provided a new insight for the exploration of fluorescence sensors based on 2D-pMOFs coupled with CRISPR/Cas14a, but also, demonstrated its universality in both nucleic acid and non-nucleic acid targets determination., (Copyright © 2021 Elsevier B.V. All rights reserved.)

As the secondary metabolites of cyanobacterial harmful algal blooms (Cyano-HABs), microcystins (MCs) were generated under various environmental and cellular conditions. The understanding of the causes of MCs generation is of great interest in the field of water treatment and environmental science. In this work, we studied how Microcystis aeruginosa (FACHB-905) cell densities affect the MCs synthetase genes (mcy) expression, microcystin-LR (MC-LR) and quorum sensing molecules (Acyl-homoserine lactones (AHLs)) production. An electrochemical sensor was developed here for sensitive and quantitative detection of MC-LR that cultured at different cell densities. The results showed that mcy expression and MC-LR concentration started to increase when the cell density reached ca. 22 × 10 6 cells/mL, and was significantly increased with increasing cell densities. Moreover, the up-regulation of AHLs with increasing cell densities revealed that MC-LR is quorum sensing-mediated. Our results undoubtedly confirmed that MC-LR was produced in a cell density-dependent way that mimics quorum sensing, and the minimum cell density (ca. 22 × 10 6 cells/mL) that was required to produce MC-LR was provided and offered a reference standard for the prevention and control of MCs pollution in the actual water environment., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

A regenerable ion-imprinted magnetic biocomposite (IIMB) was successfully synthesized for simultaneous removal of Pb 2+ using Serratia marcescens and carboxymethyl chitosan (CMC) as functional carriers, Pb 2+ was utilized as the imprinted ion, while Fe 3 O 4 served as the magnetic component. The structure and properties of IIMB were characterized by various techniques. The adsorption kinetics, isotherms and thermodynamics were applied to interpret the Pb 2+ adsorption process on IIMB. The results showed the IIMB possessed prominent uptake ability toward Pb 2+ . The pseudo-second-order kinetic (R 2 = 0.9989) and Langmuir models (R 2 = 0.9555) fitted the data well. Adsorption thermodynamics revealed that the adsorption was a spontaneous endothermic reaction. The possible adsorption mechanisms involved physical adsorption, electrostatic attraction and complexing. Moreover, because Pb 2+ can be specifically and strongly adsorbed on IIMB, a simple method for detection of Pb 2+ was established by coupling IIMB with flame atomic absorption spectrometry (IIMB-FAAS). The developed IIMB-FAAS assay can sensitively detect Pb 2+ with a linear range from 5.0 to 500.0 μg/L. The detection limit (LOD) of 0.95 μg/L as well as a quantification limit (LOQ) of 3.20 μg/L were obtained. This work proved that the IIMB could selective and efficient adsorb Pb 2+ , which provided some insights into wastewater treatment, water quality inspection and environmental remediation., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Copper is an essential metal in all organisms. Reliably quantifying and identifying the copper content and oxidation state is crucial, since the information is essential to understanding protein structure and function. Chromophoric ligands, such as Bathocuproine (BC) and its water-soluble analog, Bathocuproinedisulfonic acid (BCS), preferentially bind Cu(I) over Cu(II), and therefore have been widely used as optical probes to determine the oxidation state of copper bound by biomolecules. However, the BCS assay is commonly misused, leading to erroneous conclusions regarding the role of copper in biological processes. By measuring the redox potential of Cu(II)-BCS2 and conducting UV-vis absorption measurements in the presence of oxidizable amino acids, the thermodynamic origin of the potential artifacts becomes evident. The BCS assay was improved by introducing a strong Cu(II) chelator EDTA prior to the addition of BCS to prevent interference that might arise from Cu(II) present in the sample. The strong Cu(II) chelator rids of all the potential errors inherent in the conventional BCS assay. Applications of the improved assay to peptides and protein containing oxidizable amino acid residues confirm that free Cu(II) no longer leads to artifacts, thereby resolving issues related to this persistently misused colorimetric assay of Cu(I) in biological systems., (Copyright © 2016 Elsevier Inc. All rights reserved.)