Photosensitized covalent organic framework as a light-induced oxidase mimic for colorimetric detection of uric acid.

As large numbers of people are suffering from gout, an accurate, rapid, and sensitive method for the detection of gout biomarker, uric acid, is important for its effective control, diagnosis, and therapy. Although colorimetric detection methods based on uricase have been considered, they still have limitations as they produce toxic HO and are expensive and not stable. Here, a novel uricase-free colorimetric method was developed for the sensitive and selective detection of uric acid based on the light-induced oxidase-mimicking activity of a new photosensitized covalent organic framework (COF) (2,4,6-trimethylpyridine-3,5-dicarbonitrile-4-[2-(4-formylphenyl)ethynyl]benzaldehyde COF [DCTP-EDA COF]).

Construction of covalent organic framework nanozymes with photo-enhanced hydrolase activities for colorimetric sensing of organophosphorus nerve agents.

Construction of covalent organic frameworks (COFs)-based nanozymes is of great importance for the extensive applications in catalysis and sensing fields. In this work, a two-dimensional COF (DAFB-DCTP COF) was fabricated via Knoevenagel condensation reaction. The integration of catalytically active sites of pyridine groups into the donor-acceptor (D-A) conjugated skeleton endows DAFB-DCTP COF with both hydrolytic and photosensitive properties.

Simultaneous detection and separation of uranium based on a fluorescent amidoxime-functionalized covalent organic polymer.

To ensure the long-term sustainable development of nuclear energy as well as the prevention and control of uranium pollution, new materials that can simultaneously detect and separate uranium are still urgently needed. Herein, a new fluorescent covalent organic polymer (COP), namely HT-COP-AO, was synthesized andemployed as both the fluorescent probe and absorbent for simultaneous uranium detection and separationconsidering its excellent fluorescence property and strong uranium coordination ability. The results showed that the fluorescence of HT-COP-AO was quickly quenched by uranium within 2 min, and the limit of detection was 0.