Rapid,Quantitative, and Ultrasensitive Point‐of‐Care Testing: A Portable SERS Reader for Lateral Flow Assays in Clinical Chemistry

The design of a portable Raman/SERS‐LFA reader with line illumination using a custom‐made fiber optic probe for rapid, quantitative, and ultrasensitive point‐of‐care testing (POCT) is presented. The pregnancy hormone human chorionic gonadotropin (hCG) is detectable in clinical samples within only 2–5 s down to approximately 1.6 mIU mL^?1. This acquisition time is several orders of magnitude shorter than those of existing approaches requiring expensive Raman instrumentation, and the method is 15‐times more sensitive than a commercially available lateral flow assay (LFA) as the gold standard. The SERS‐LFA technology paves the way for affordable, quantitative, and ultrasensitive POCT with multiplexing potential in real‐world applications, ranging from clinical chemistry to food and environmental analysis as well as drug and biowarfare agent testing.     

A Transient-Directing-Group Strategy Enables Enantioselective Reductive Heck Hydroarylation of Alkenes

Metal-coordinating directing groups have seen extensive use in the field of transition-metal-catalyzed alkene functionalization; however, their waste-generating installation and removal steps limit the efficiency and practicality of reactions that rely on their use. Inspired by developments in asymmetric organocatalysis, where reactions rely on reversible covalent interactions between an organic substrate and a chiral mediator, we have developed a transient-directing-group approach to reductive Heck hydroarylation of alkenyl benzaldehyde substrates that proceeds under mild conditions. Highly stereoselective migratory insertion is facilitated by in situ formation of an imine from catalytic amounts of a commercially available amino acid additive. Computational studies reveal an unusual mode of enantioinduction by the remote chiral center in the transient directing group.     

Brønsted Acidic Ionic Liquid-Catalyzed Synthesis of 14-Aryl-14H-dibenzo[a,j]xanthenes with Controlled Microwave Heating under Solvent-Free Conditions

Russian Journal of Organic Chemistry - 1-Methyl-3-sulfo-1H-imidazol-3-ium chloride ([Msim]Cl) catalyzed the condensation of β-naphthol with aromatic aldehydes under microwave irradiation. This...     

Determination of Chlorpyrifos Pesticide Residue in Bell Peppers Grown in Dalat (Vietnam) by GC-MS/MS Using QuEChERS Extraction

Journal of Analytical Chemistry - Triple quadrupole mass spectrometry was used for the direct, quick and quantitative determination of chlorpyrifos residue in bell peppers using the QuEChERS...     

Chemical Constituents and Biological Activities of the Leaves of Knema saxatilis

Chemistry of Natural Compounds -     

On distortion of normal subgroups

Geometriae Dedicata - We examine distortion of finitely generated normal subgroups. We show a connection between subgroup distortion and group divergence. We suggest a method computing the...     

Spin exchange in piperidineoxyl polyradicals with bridges containing methylene groups

The temperature-dependent dynamics of the intramolecular electron spin exchange in tri- and tetraradicals in which piperidineoxyl rings are connected via methylene groups are studied using EPR technique. The thermodynamic characteristics of conformational transitions in these polyradicals are obtained. The effect of the substitution of an ?OH group for the >C=O group at the fourth position of the piperidineoxyl rings of the tetraradicals on the dynamics of spin-exchange interaction in them is examined. The structure of a new asymmetrical nitroxide triradical is determined from X-ray structural analysis.     

The linear conjugation problem for bi-analytic functions

We consider a classical problem on linear conjugation problem for bi-analytic functions on smooth contour. We obtain explicit formula of a solution to a problem and describe necessary and sufficient conditions of its solvability.