The Application of Graphene Field-Effect Transistor Biosensors in COVID-19 Detection Technology: A Review.

Coronavirus disease 2019 (COVID-19) is a disease caused by the infectious agent of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). The primary method of diagnosing SARS-CoV-2 is nucleic acid detection, but this method requires specialized equipment and is time consuming. Therefore, a sensitive, simple, rapid, and low-cost diagnostic test is needed.

Fabrication and enhanced visible-light photocatalytic Hproduction of B-doped N-deficient g-CN/CdS Hybrids with robust 2D/2D hetero-interface interaction.

2D layered photocatalysts with proper electronic structure have sparked much attention in the field of visible-light photocatalysis for Hproduction. Herein, by simply calcining the mixture of ultrathin g-CN(CNN) and NaBH, heteroatom B and N defect were simultaneously introduced into g-CN. The obtained modified g-CN(BDCNN) was further coupled with 2D flower-like CdS nanosheet.

Three-Component Synthesis of Dioxaphosphorane-Fused Diphosphacycles Exhibiting Unique Dynamic Fluorescence "On/Off" Properties.

Rigidly planar polycyclic phosphacycles featuring an internal dioxaphosphorane are promising photofunctional materials. However, the lack of efficient synthetic methods resulted in limited structural diversities which significantly hampered extensive study. Herein, we report a straightforward three-component synthesis of novel dioxaphosphorane-fused diphosphacycles with distinctive photophysical properties.

Multi-response gelation based on the molecular assembly of Sudan I dye derivatives for phase selective gelators and chemosensors.

Sudan I dye-based smart low molecular weight gelators with/without a perfluoroalkyl group have been successfully synthesized and characterized by rheological measurements, scanning electron microscopy (SEM), IR, and NMR spectroscopies. The gelation behaviors in response to temperature, pH changes, metal cations, and UV-vis light irradiation are investigated. Compounds 1 and 2 could selectively sense the Cu cation in the presence of other metal cations.

self-assembly fabrication of ultrathin sheet-like CuS modified g-CNheterojunction and its enhanced visible-light photocatalytic performance.

Photocatalysts with heterojunction structure have been widely used for organic degradation. In this study, CuS/g-CNheterojunction was formed byself-assembly via a simply hydrothermal method. A series of characterizations were applied to analyzing the morphology, structure, optical properties and photo-induced electron transfer of the samples.

Ultrasensitive and Regenerative Transistor Sensor Based on Dynamic Covalent Chemistry.

Field-effect transistor (FET) sensors require not only high sensitivity but also excellent regeneration ability before widespread applications are possible. Although some regenerative FETs have been reported, their lowest limit of detection (LoD) barely achieves 10 mol L. Here, we develop a graphene FET with a regenerative sensing interface based on dynamic covalent chemistry (DCvC).

Enhanced Hevolution performance by carbonized SiC/g-CNheterojunction under visible-light illumination.

In this study, carbonized silicon carbide/graphitic carbon nitride ((SiC/C)/g-CN) composites were fabricated via a facile calcination method. The optimal SiC/C/g-CNcomposite shows an excellent visible-light photocatalytic activity for water splitting, with the highest hydrogen evolution amount being 200.2mol, which is four times higher than that of pure g-CNwhen triethanolamine and platinum (1.

Ultraprecise Antigen 10-in-1 Pool Testing by Multiantibodies Transistor Assay.

Effective screening of infectious diseases requires a fast, cheap, and population-scale testing. Antigen pool testing can increase the test rate and shorten the screening time, thus being a valuable approach for epidemic prevention and control. However, the overall percent agreement (OPA) with polymerase chain reaction (PCR) is one-half to three-quarters, hampering it from being a comprehensive method, especially pool testing, beyond the gold-standard PCR.

2,2,2-Tri-fluoro-N-(2-iodo-phen-yl)acetamide.

The three F atoms in the title compound, C8H5F3INO, are disordered over two sets of sites [relative occupancies = 0.615 (14):0.385 (14)].

Ethyl N-(3-cyano-1H-indol-2-yl)form-imidate.

In the title compound, C12H11N3O, the C=N imino bond is in an E conformation. In the crystal, adjacent mol-ecules are linked by N-H⋯Ncyano hydrogen bonds, forming a chain running along [110].

Total synthesis of a marine alkaloid--rigidin E.

In the present paper, we report an efficient total synthesis of a marine alkaloid, rigidin E. The key tetrasubstituted 2-amino-3-carboxamidepyrrole intermediate was synthesized by cascade Michael addition/intramolecular cyclization between N-(2-(4-(benzyloxy)phenyl)-2-oxoethyl)methanesulfonamide and 3-(4-(benzyloxy)phenyl)-2-cyano-N-methylacrylamide. Subsequent carbonylation with triphosgene catalyzed by I(2) and deprotection of benzyl groups afforded rigidin E in 21% overall yield.

Synthesis of thioethers via metal-free reductive coupling of tosylhydrazones with thiols.

A metal-free procedure for the synthesis of thioethers is described via the base-promoted reductive coupling of tosylhydrazones with thiols through an insertion of a carbene into the S-H bond.

Silica gel-promoted tandem addition-cyclization reactions of 2-alkynylbenzenamines with isothiocyanates.

Tandem addition-cyclization reactions of 2-alkynylbenzenamines with isothiocyanates promoted by silica gel are described. This reaction proceeds smoothly at 80 degrees C under metal- and solvent-free conditions, which provides an efficient and practical route for the generation of 2,4-dihydro-1H-benzo[d][1,3]thiazines. The recovered silica gel could be reused for several times.