Multi-component strategy for the preparation of covalent organic frameworks-based stationary phase for high resolution separation of isomers.

Functionalization of covalent organic frameworks (COFs) is a critical means to prepare COF-based gas chromatography stationary phases for high-resolution separation. Here, we report a simple and controllable multi-component strategy for the functionalization of COF stationary phases. As a proof of concept, a COF fabricated from 1,3,5-tris(4-aminophenyl) benzene (Tab) and 2,5-dihydroxy-1,4-benzenedicarboxaldehyde (DHTA), Tab-DHTA, was chosen as a model.

Boronate affinity molecularly imprinted covalent organic framework for highly selective recognition and extraction of zearalenone.

Selective and sensitive determination of zearalenone (ZEN) in food matrices is crucial for risk assessment and mycotoxin control due to its high toxicity. Herein, we introduce a boron affinity molecularly imprinted covalent organic framework (BA-MICOF) for selective extraction of ZEN from cereal. The Povarov reaction was employed for one-pot synthesis of boric acid incorporated COF (BA-COF) to avoid complex post-modification.

Unlocking Enhanced Detection of Perfluoroalkanesulfonic Acids via Fluorinated Nonpolar 3D Covalent Organic Frameworks-Based Ambient Probe Nanoelectrospray Ionization Mass Spectrometry.

The trace levels and severe matrix interferences greatly limited the determination of stable, persistent, and long-range-transported perfluoroalkanesulfonic acids (PFSAs) in complex environments. Here, we design and prepare the first fluorinated nonpolar 3D COF (TFPM-Pa-CF) as an adsorbent, consisting of tetrakis(4-formylphenyl)methane (TFPM) and 2,5-diaminobenzo-trifluoride (Pa-CF) for adsorption and extraction of PFSAs. The proposed TFPM-Pa-CF demonstrates excellent adsorption capacity (509.

Kinetic Method Coupled with Thermal-Assisted Paper Spray Ionization Mass Spectrometry for Direct Determination of Enantiomeric Excess of Multiple d/l-Amino Acids in Functional Foods.

Amino acids are commonly used as nutritional fortification substances in functional foods, and their chiral configuration is an important determinant of food function. Rapid chiral screening methods are urgently needed in food analysis but are limited by the long-time chiral separation and matrix interference. In this study, we show a kinetic method coupled to thermal-assisted paper spray ionization mass spectrometry for direct determination of enantiomeric excess () of multiple d/l-amino acids in complex food matrixes without sample pretreatment.

Designing flexible aliphatic linker based molecular imprinted covalent organic framework for rapid and selective extraction and detection of trace zearalenone.

Food and environment contaminations by zearalenone (ZEN) has aroused serious issues in public health. Sensitive and accurate detection of ZEN remains a daunting challenge due to complex interference and low residue in real samples. Herein, we report a novel molecular imprinted covalent organic framework with flexible aliphatic linkers (ALCOF-MIP) for rapid and selective extraction of ZEN in real samples.

Calixarene incorporated molecular imprinting on covalent organic framework for supramolecular recognition and specific extraction of citrinin.

Specific recognition and selective extraction of mycotoxin in environmental and food matrixes is significant to guarantee public health. Covalent organic frameworks (COFs) are promising adsorbents with tailorable functionality, but their low binding affinity and poor selectivity hamper their wide application for selective extraction of trace mycotoxin from complex matrix. Herein, we report calixarene incorporated molecular imprinting on COF to prepare molecularly imprinted calix[4]arene-containing COF (MICOF-CX4) for supramolecular recognition and specific adsorption of citrinin.

Aptamer-Conjugated Covalent-Organic Framework Nanochannels for Selective and Sensitive Detection of Aflatoxin B1.

Sensitive and selective detection of trace aflatoxin B1 (AFB1) in foods is of great importance to guarantee food safety and quality but still challenging because of its trace amount and the interference from the complex food matrix. Here, we report the integration of aptamer (Apt) and an ordered 2D covalent organic framework (COF) to solid-state anodic aluminum oxide (AAO) nanochannels (Apt/COF/AAO) for selective and sensitive detection of trace AFB1. The high specificity of Apt for AFB1 led to a selective change in the surface charge of Apt/COF/AAO and in turn the current change of the nanochannel, permitting the selective and sensitive determination of trace AFB1 in complex food samples.

Tuning the planarity of molecularly imprinted covalent organic frameworks for selective extraction of ochratoxin A in alcohol samples.

Here, we report a monomer planarity modulation strategy for room-temperature constructing molecularly imprinted-covalent organic frameworks (MI-COFs) for selective extraction of ochratoxin A (OTA). 2,4,6-triformylphloroglucinol (Tp) was used as basic building block, while three amino monomers with different planarity were employed as modulators to explore the effect of planarity on the selectivity of MI-COFs. The MI-TpTapa constructed from Tp and the lowest planarity of monomer Tapa gave the highest selectivity for OTA, and was further used as the adsorbent for dispersed-solid phase extraction (DSPE) of OTA in alcohol samples.

Pore Size Adjustment Strategy for the Fabrication of Molecularly Imprinted Covalent Organic Framework Nanospheres at Room Temperature for Selective Extraction of Zearalenone in Cereal Samples.

Covalent organic frameworks (COFs) are attractive adsorbents for sample pretreatment due to their unique structure and properties. However, the selectivity of COFs for the extraction of hazardous compounds is still limited due to the lack of specific interactions between COFs and targets. Herein, we report a pore size adjustment strategy for room-temperature synthesis of molecularly imprinted COF (MICOF) for selective extraction of zearalenone (ZEN) in complex food samples.

General Two-Step Method for the Fabrication of Covalent-Organic Framework-Bound Open-Tubular Capillary Columns for High-Resolution Gas Chromatography Separation of Isomers.

Covalent organic frameworks (COFs) are promising as stationary phases for gas chromatography (GC). The successful anchoring of COFs to the inner walls of the capillary with good uniformity is an important prerequisite to ensure the excellent separation performance of columns. However, current methods for the fabrication of COF-based capillary columns cannot always meet this requirement when faced with different COFs, which hampers the further development of COF-based GC stationary phases.

Irreversible fluorine covalent organic framework based probe nanoelectrospray ionization mass spectrometry for direct and rapid determination of perfluoroalkyl carboxylic acids.

Probe nanoelectrospray ionization mass spectrometry (PESI-MS) is practically desirable for rapid and ultra-sensitive analysis of trace contaminants in environment, but limited with the stable and selective probe coating. Herein, we show the design and preparation of irreversible fluorine-based covalent organic framework (TFPPA-F) covalently bonded probe to couple with ESI-MS (TFPPA-F-PESI-MS) for direct and rapid determination of perfluoroalkyl carboxylic acids (PFCAs) in environmental water. Chemical bonding coating of irreversible crystalline TFPPA-F not only improved stability of the probe, but also offered accessible multiple interactions including hydrophobic, hydrogen bonding and F-F interactions to promote the kinetics and selectivity for PFCAs.

Organic Mass Cytometry Discriminating Cycle Stages of Single Cells with Small Molecular Indicators.

Cell cycle is a significant factor toward cellular heterogeneity, so cell cycle discrimination is a precise measurement on the top of single-cell analysis. Single-cell analysis based on organic mass spectrometry has received great attention for its unique ability to profile single-cell metabolome, but the influence of cell cycle on cellular metabolome heterogeneity has been overlooked until now due to the lack of a compatible cell cycle discrimination method. Here, we report a robust protocol based on the combination of three small molecular indicators, consisting of two small molecular labels (Hoechst and docetaxel) and one cellular endogenous compound [phosphocholine (34:1)], to discriminate single cells at different cycle stages in real time by organic mass cytometry.

The emerging role of pyroptosis-related inflammasome pathway in atherosclerosis.

Atherosclerosis (AS), a chronic sterile inflammatory disorder, is one of the leading causes of mortality worldwide. The dysfunction and unnatural death of plaque cells, including vascular endothelial cells (VEC), macrophages, and vascular smooth muscle cells (VSMC), are crucial factors in the progression of AS. Pyroptosis was described as a form of cell death at least two decades ago.

Nanothorn Filter-Facilitated Online Cell Lysis for Rapid and Deep Intracellular Profiling by Single-Cell Mass Spectrometry.

Mass spectrometry combined with flow cytometry is emerging for high-throughput single-cell metabolite analysis but still has problems with limited intracellular information coverage. Here, we show a simple and efficient all-in-one system integrating cell injection, cell extraction, online cell lysis, analyte ionization, and mass spectrometric detection for rapid single-HeLa-cell screening with in-depth profiling of cellular metabolites and drugs. Zinc oxide nanothorn-decorated filters with three bore sizes (5.

[Constructing Brain Aβ-Targeting Nanoparticles Loaded with EGCG for Treating Alzheimer's Disease in Mice].

Objective: To construct a nanodelivery system surface-modified with RD2 peptide (polypeptide sequence PTLHTHNRRRRR) for brain tissue penetration and β-amyloid (Aβ) binding. Epigallocatechin-3-gallate (EGCG) was selected for encapsulation in the targeted delivery system and its therapeutic potential for Alzheimer's disease (AD) was investigated.

Methods: EGCG-load nanoparticles (NP/EGCG), NP/EGCG with RD2 peptide surface modification (RD2-NP/EGCG), as well as RD2 peptide-modified blank nanoparticles (RD2-NP) were prepared and characterized.