The unintentional dissemination of uranium into environment poses substantial risks to both food sources and human populations. An advanced method for convenient and accurate detection of uranium in food is thus a pressing need. Herein, a novel magnetic amidoxime functionalized covalent organic framework (TpDb-AO@FeO), prepared with 2,5-dinitrobenzonitrile, 1,3,5-triformylphloroglucinol and hydroxylamine hydrochloride, was synthesized as adsorbent for magnetic-solid phase extraction (MSPE) of UO.
View Article and Find Full Text PDFNanochannel membranes are promising materials for enantioselective sensing. However, it is difficult to make a compromise between the selectivity and permeability in traditional nanochannel membranes. Therefore, new types of nanochannel membranes with high enantioselectivity and excellent permeability should be explored for chiral analysis.
View Article and Find Full Text PDFSpecific 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.
View Article and Find Full Text PDFSensitive 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.
View Article and Find Full Text PDFCovalent organic frameworks (COFs) are attractive materials for sample pretreatment due to their tunable structures and functions. However, the precise recognition of contaminant in complex environmental matrices by COFs remains challenging owing to their insufficient specific active sites. Herein, we report Co coordination-assisted molecularly imprinted flexible COF (MI-COF@Co) for selective recognition of ochratoxin A (OTA).
View Article and Find Full Text PDFHere, 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.
View Article and Find Full Text PDFThe scarcity of selective adsorbents for efficient extraction and removal of microcystins (MCs) from complex samples greatly limits the precise detection and effective control of MCs. Three-dimensional covalent organic frameworks (3D COFs), characterized by their large specific surface areas and highly ordered rigid structure, are promising candidates, but suffer from lack of specific recognition. Herein, we design to engineer molecularly imprinted cavities within 3D COFs via molecularly imprinted technology, creating a novel adsorbent with exceptional selectivity, kinetics and capacity for the efficient extraction and removal of MCs.
View Article and Find Full Text PDFUnderstanding the individual fluorescence response mechanism of covalent organic frameworks (COFs) at a single-crystal level is of great significance for the rational design of COF-based microsensors but unreachable because all previous COF-based sensors are performed with average fluorescence response behavior of various sized polycrystalline COFs. Herein, we design to explore the fluorescence response of a monodisperse single-crystal COF and further reveal the individual heterogeneity of the response mechanism. Three-dimensional single-crystal COF-301 (SCOF-301) with an intramolecular H-bond-induced excited-state intramolecular proton-transfer effect is selected as a proof-of-concept SCOF.
View Article and Find Full Text PDFCovalent 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.
View Article and Find Full Text PDFCovalent organic frameworks (COFs) are promising adsorbents for extraction, but their selectivity for molecular recognition remains a challenging issue due to the very limited structural design with rigid structure. Herein, we report an elegant strategy for the design and synthesis of molecularly imprinted flexible COFs (MI-FCOFs) via one-pot reaction between the flexible building block of 2,4,6-tris(4-formylphenoxy)- 1,3,5-triazine and linear 4-phenylenediamine for selective extraction of aflatoxins. The flexible chain structure enabled the developed MI-FCOF to adjust the shape and conformation of frameworks to suit the template molecule, giving high selectivity for aflatoxins recognition.
View Article and Find Full Text PDFAs an emerging porous material, hydrogen-bonded organic framework materials (HOFs) still pose application challenges. In this work, the designed type "I + II" heterojunction extracted hot electrons from HOFs using quantum dots (QDs) and polypyrrole (Ppy), improving the stability and photoelectrochemical performance of materials. In addition to serving as a potential well, electropolymerized Ppy was used as a recognition element for bisphenol A (BPA), and a novel self-powered molecularly imprinted photoelectrochemical (MIP-PEC) sensor was designed.
View Article and Find Full Text PDFBackground: Gastric cancer (GC) is the most commonly diagnosed digestive system malignancy with a dismal survival outcome. The prognostic value of ubiquitination-related genes (URGs) in GC has yet to be discovered.
Methods: Two GC cohort datasets were obtained from the Cancer Genome Atlas Program (TCGA) and Gene Expression Omnibus (GEO) databases.
Chiral flavor substances play an important role in the human perception of different tastes. Here, we report a pure covalent-organic framework (COF) membrane nanochannel in combination with a chiral gold nanoparticles (AuNPs) selector for sensing chiral flavor substances. The pure COF membrane with a proper pore size is selected as the nanochannel, while l-cysteine-modified AuNPs (l-Cys-AuNPs) are used as the chiral selector.
View Article and Find Full Text PDFCovalent 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.
View Article and Find Full Text PDFCarbon dots (CDs)-enabled agriculture has been developing rapidly, but small-scale synthesis and high costs hinder the agricultural application of CDs. Herein, biomass-derived carbon dots (B-CDs) were prepared on a gram-level with low cost, and these B-CDs significantly improved crop photosynthesis. The B-CDs, exhibiting small size and blue fluorescence, were absorbed by crops and enhanced photosynthesis via light-harvesting.
View Article and Find Full Text PDFACS Appl Mater Interfaces
July 2023
Development of novel functional materials for effective isomer separation is of great significance in environmental science, chemical industry, and life science due to the different functions of isomers. However, the similar physicochemical properties of isomers make their separation greatly challenging. Here, we report the fabrication of trifluoromethyl-functionalized 2D covalent organic framework (COF) TpTFMB with 2,2'-bis(trifluoromethyl)benzidine (TFMB) and 1,3,5-triformylphloroglucinol (Tp) for the separation of isomers.
View Article and Find Full Text PDFAlthough polycrystalline covalent organic frameworks (PCOFs) have already shown great potential as stationary phases for chromatography, irregular shape and size distribution of PCOFs make regulation of particle size of PCOFs for high separation performance impossible, which is accessible by the application of single-crystalline COFs (SCOFs). Herein, we showed preparation of three-dimensional SCOF (SCOF-303) bonded capillaries (SCOF-303-capillary) with different particle sizes (about 0.4-1.
View Article and Find Full Text PDFProbe 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.
View Article and Find Full Text PDFElectronic devices with tactile and pressure-sensing capabilities are becoming increasingly popular in the automatic industry, human motion/health monitoring, and artificial intelligence applications. Inspired by the natural nanotopography of the cicada wing, we propose here a straightforward strategy to fabricate a highly sensitive tactile sensor through nanotexturing of erected polyaniline (PANI) nanoneedles on a conductive and elastic three-dimensional (3D) carbon skeleton. The robust and compressible carbon networks offer a resilient and conducting matrix to catering complex scenarios; the biomimetic PANI nanoneedles firmly and densely anchored on a 3D carbon skeleton provide intimate electrical contact under subtle deformation.
View Article and Find Full Text PDFNanosilicon applications have been shown to increase plant defenses against both abiotic and biotic stresses. Silicon quantum nanodots (Si NDs), a form of nanosilicon, possess excellent biological and physiochemical properties (, minimal size, high water solubility, stability, and biocompatibility), potentially making them more efficient in regulating plant responses to stress than other forms of silicon. However, to date, we still lack mechanistic evidence for how soil-applied Si NDs alter the regulation of plant physical and chemical defenses against insect herbivores.
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