Simultaneous Detection and Decontamination of Dichromate Ions: The Fluorescence Response and Photocatalysis of Thiadiazole-Modified Zr-Metal-Organic Frameworks.

The simultaneous analysis and removal of highly toxic hexavalent chromium (Cr (VI)) in contaminated water via an easy method remain a serious task. Based on the guidance of bibliometric analysis, a thiadiazole ligand-modified zirconium metal-organic framework (Zr-MOF) heralds a new and simple approach to Cr (VI) treatment. The concentration can be determined by fluorescence quenching with a low detection limit of 1.4 µM and a high quenching constant of 6.88 × 103 M-1. For the sensing mechanism, the fluorescence intensity of the Zr-MOF decreased rapidly due to the competition of Cr (VI) with the Zr-MOF for absorption excitation energy and the induction of Zr-MOF aggregation. The analysis system also displayed satisfactory stability and applicability. Apart from sensing application, Zr-MOF can convert Cr (VI) to Cr (III), and the reduction rate constant was 0.004 min-1 under irradiation. Therefore, the bifunctional Zr-MOF provided a potential application method for controlling the pollution caused by Cr (VI) in wastewater.

Ti3C2Tx MXene -facilitated non-selective trapping effect: Efficient SERS detection of exosomal PD-L1.

Biosensors developed through a sandwich approach have demonstrated favorable detection performance for exosomal programmed cell death 1 ligand 1 (ExoPD-L1) detection. However, the reported PD-L1 antibodies, peptides, and aptamers utilized in these biosensors typically bind to the extracellular region, with overlapping binding sites that severely constrain the fabrication of biosensors. In this study, we present a simple approach to specifically identify and analyze ExoPD-L1 through the non-selective trapping effect of Ti3C2TX (X=-O, -F, -OH) MXene on exosomes via the formation of Ti-O-P complexation, and the selective capture of peptide-functionalized Au@MPBA (4-Mercaptophenylboronic acid) @SiO2 surface enhanced Raman scattering (SERS) tags on ExoPD-L1. The biosensor delivered a both hypersensitive and reliable performance in exosome detection with a low limit of detection (20.74 particles/mL) in the linear range of 102 to 5×106 particles/mL. Furthermore, the biosensor demonstrated excellent stability and interference resistance in detecting ExoPD-L1 in clinical serum samples, enabling the easy differentiation of breast cancer patients from healthy controls. This work provides new insights into the design of biosensors for exosome detection and can serve as a replicable template for sandwich immunoassay detection for other types of sensors, including but not limited to SERS.

[Preparation of novel phenyl boronic acid functionalized silica gel using triazo-cyanide click chemistry and its application in glycoprotein/glycopeptide selective enrichment].

The application of boronic acid affinity chromatography to glycoprotein/glycopeptide enrichment is increasingly maturing. The enrichment selectivity, biocompatibility, and facile operation protocol are key aspects in efficient enrichment methods. In this work, a novel triazo-cyanide boronic acid functionalized material (TCNBA) was prepared using triazo-cyanide click chemistry. The TCNBA was proved to be successfully synthesized through infrared ray (IR) characterization. Subsequently, the glycopeptide/glycoprotein enrichment selectivity of the TCNBA was evaluated. Matrix-assisted laser desorption/ionization time-of-flight mass (MALDI-TOF MS) was employed for the glycopeptide enrichment selectivity evaluation. Taking the digestion of horseradish peroxidase (HRP) and immunoglobulin G (IgG) as samples, 13 and 11 glycopeptides could be characterized with improved signals after TCNBA enrichment, respectively. High abundance non-glycopeptides could be removed effectively from the eluting fraction. This result indicates the high glycopeptide enrichment selectivity of TCNBA. In addition, a mixture of HRP and bovine serum albumin (BSA) enzymatic solution (1:10, amount of substance ratio) was utilized as a sample, and five glycopeptide signals could be identified following enrichment. To evaluate the glycoprotein enrichment selectivity, sodium salt-polyacrylamide gel electrophoresis (SDS-PAGE) was adopted as an evaluation method. Mixtures of HRP, IgG, BSA, and ribonuclease B (RNaseB) proteins were employed as samples, and the results demonstrated that TCNBA had a high glycoprotein enrichment selectivity. The application of TCNBA to the analysis of a real biosample was also evaluated using human plasma. The results indicated the TCNBA could be utilized in large-scale glycoprotein analysis.