Hydrogen Isotope Labeling of Pharmaceuticals Via Dual Hydrogen Isotope Exchange Pathways Using CdS Quantum Dot Photocatalyst.

Isotopic labeling is a powerful technique extensively used in the pharmaceutical industry. By tracking isotope-labeled molecules, researchers gain unique and invaluable insights into the pharmacokinetics and pharmacodynamics of new drug candidates. Hydrogen isotope labeling is particularly important as hydrogen is ubiquitous in organic molecules in biological systems, and it can be introduced effectively through late-stage hydrogen isotope exchange (HIE).

CdS Quantum Dot Gels as a Direct Hydrogen Atom Transfer Photocatalyst for C-H Activation.

Here, we report CdS quantum dot (QD) gels, a three-dimensional network of interconnected CdS QDs, as a new type of direct hydrogen atom transfer (d-HAT) photocatalyst for C-H activation. We discovered that the photoexcited CdS QD gel could generate various neutral radicals, including α-amido, heterocyclic, acyl, and benzylic radicals, from their corresponding stable molecular substrates, including amides, thio/ethers, aldehydes, and benzylic compounds. Its C-H activation ability imparts a broad substrate and reaction scope.

Control over Charge Separation by Imine Structural Isomerization in Covalent Organic Frameworks with Implications on CO Photoreduction.

Two-dimensional covalent organic frameworks (COFs) are an emerging class of photocatalytic materials for solar energy conversion. In this work, we report a pair of structurally isomeric COFs with reversed imine bond directions, which leads to drastic differences in their physical properties, photophysical behaviors, and photocatalytic CO reduction performance after incorporating a Re(bpy)(CO)Cl molecular catalyst through bipyridyl units on the COF backbone (Re-COF). Using the combination of ultrafast spectroscopy and theory, we attributed these differences to the polarized nature of the imine bond that imparts a preferential direction to intramolecular charge transfer (ICT) upon photoexcitation, where the bipyridyl unit acts as an electron acceptor in the forward imine case (f-COF) and as an electron donor in the reverse imine case (r-COF).

Electrochemical Gelation of Metal Chalcogenide Quantum Dots: Applications in Gas Sensing and Photocatalysis.

ConspectusMetal chalcogenide quantum dots (QDs) are prized for their unique and functional properties, associated with both intrinsic (quantum confinement) and extrinsic (high surface area) effects, as dictated by their size, shape, and surface characteristics. Thus, they have considerable promise for diverse applications, including energy conversion (thermoelectrics and photovoltaics), photocatalysis, and sensing. QD gels are macroscopic porous structures consisting of interconnected QDs and pore networks in which the pores may be filled with solvent (i.

Quantum dot gels as efficient and unique photocatalysts for organic synthesis.

Here we report CdS quantum dot (QD) gels as highly efficient and unique photocatalysts for organic synthesis. We found that the photocatalytic activity of CdS QD gel was superior to phosphine oxide- and thiolate-capped CdS QDs for dehalogenation and α-amine arylation reactions because of the high accessibility of its surface sites to the substrates. In addition, we discovered the unique reactivity of CdS QD gel for ring-opening during α-amine arylation of tetrahydroisoquinoline the reductive cleavage of C-N bonds.

Elimination and ecotoxicity evaluation of phthalic acid esters from textile-dyeing wastewater.

Phthalic acid esters (PAEs), presented in fabrics, surfactants and detergents, were discharged into the ecosystem during textile-dyeing wastewater treatment and might have adverse effects on water ecosystems. In this study, comprehensive investigations of the content and component distributions of 12 PAEs across different units of four textile-dyeing wastewater plants were carried out in Guangdong Province, China. Ecotoxicity assessments were also conducted based on risk quotients (RQs).

[Investigation on human Cryptosporidium infection in local area of Anhui Province].

Objective: To investigate the status of Cryptosporidium infection in the population in the local area of Anhui Province, and discuss the risk factors of the infection, so as to provide the evidence for the prevention and treatment of cryptosporidiosis.

Methods: Qianshan County and Lingbi County of Anhui Province were selected as investigation spots, and the oocysts of Cryptosporidium in the feces of the investigation objects and the specific IgG antibody against Cryptosporidium in the serum were checked by using the pathogenic modified acid fast staining method and ELISA, respectively, so as to determine the status of Cryptosporidium infection in these investigation objects. At the same time, the questionnaire surveys were conducted in the investigation objects so as to know about the risk factors of Cryptosporidium infection.

Genotypes and mouse virulence of Toxoplasma gondii isolates from animals and humans in China.

Background: Recent population structure studies of T. gondii revealed that a few major clonal lineages predominated in different geographical regions. T.