Lateral flow immunoassay of human troponin-I

an immunochromatographic assay for a rapid determination of troponin-I, in which gold nanoparticles were used as visual tags, was developed. The optimum analysis conditions were determined. The detection limit of the assay was 1 ng/mL, and the coefficient of variation did not exceed 10%.     

Determination of gallium in biological fluids using inductively coupled plasma mass spectrometry

A procedure for the determination of gallium in biological fluids by inductively coupled plasma mass spectrometry was developed. The detection limits of gallium calculated from the 3s value were 60 ng/L for urine, 32 ng/L for a model solution of intestinal juice, and 50 ng/L for serum. The accuracy of the procedure was tested using a standard addition method. The nature of a background signal on the masses of gallium isotopes was studied with the use of a high-resolution mass spectrometer, and the background concentration of gallium in biological fluids was evaluated (5–7 ng/L). It was found that a background level in measurements performed on a quadrupole mass spectrometer depends on the interfering influence of polyatomic ions with close m/z ratios rather than on the background concentration of gallium. The procedure makes it possible to study the stability of pharmaceutical preparations based on gallium in biological media, their metabolism, and the excretion of preparations from the body.     

Model‐independent structure and resonant X‐ray spectra of intermediate smectic phases

It is shown that the orientational structure of intermediate smectic phases can be determined using the symmetry properties of the general free energy with arbitrary orientational coupling between smectic layers, without addressing a particular model. The structure of three‐ and four‐layer intermediate phases, obtained in this way, corresponds to experimental data. The same method enables one to predict the structure of intermediate phases with periodicity of five and six layers, which have not been observed experimentally so far. The resonant X‐ray spectra of the five‐ and six‐layer intermediate phases with predicted structure have also been calculated. These spectra are characterized by a number of features which enable one to distinguish five‐layer and six‐layer intermediate phases from phases with smaller periods.     

Hydrophobization of coarse calico by wet treatment in aluminum chloride solutions

This paper describes the method of wet chemistry used for hydrophobization of coarse calico surface. It was found that hydrophobicity of coarse calico surface is achieved by the formation of aluminum oxide on the surface. An experimental plan was drawn up according to the Taguchi method. The effect of soap solution temperature, aluminum chloride solution concentration, sample treatment time in aluminum chloride solution and heat treatment temperature on water absorption, contact angle, capillary absorption and calico moisture content was studied. The dependencies of hygroscopic properties on the process parameters were obtained. Capillary absorption and water absorption of the test samples increased with increasing concentration of aluminum chloride solution. An increase in the processing time of coarse calico samples in an aluminum chloride solution leads to a decrease in the hydrophobicity of the samples. The characteristics of the dependencies of hygroscopic properties on the temperature of heat treatment and the temperature of the soap solution are similar.

     

Synthesis and halocyclization of N- and O-propargyl derivatives of quinolin-2(1H)-ones

Russian Chemical Bulletin - The alkylation of 4-methyl- and 4,8-dimethylquinolin-2(1H)-ones with propargyl bromide gave 4-methyl-N-propargylquinolin-2(1H)-one and...     

Epitaxial gallium oxide on a SiC/Si substrate

Well-textured gallium oxide β-Ga₂O₃ layers with a thickness of ~1 μm and a close to epitaxial layer structure were grown by the method of chloride vapor phase epitaxy on Si(111) wafers with a nano-SiC buffer layer. In order to improve the growth, a high-quality silicon carbide buffer layer ~100 nm thick was preliminarily synthesized by the substitution of atoms on the silicon surface. The β-Ga₂O₃ films were thoroughly investigated using reflection high-energy electron diffraction, ellipsometry, X-ray diffraction, scanning electron microscopy, and micro-Raman spectroscopy. The investigations revealed that the films are textured with a close to epitaxial structure and consist of a pure β-phase Ga₂O₃ with the (\(\overline 2 01\)) orientation. The dependence of the dielectric constant of epitaxial β-Ga₂O₃ on the photon energy ranging from 0.7 to 6.5 eV in the isotropic approximation was measured.     

Measurement of tensor analyzing powers in deuteron photodisintegration

A new accurate measurement of the tensor analyzing powers T20, T21, and T22 in deuteron photodisintegration has been performed. Wide-aperture nonmagnetic detectors allowed broad kinematic coverage in a single set up: E(gamma)=25 to 600 MeV, and theta(p)(cm)=24 degrees to 48 degrees and 70 degrees to 102 degrees . The new data provide a significant improvement over the few existing measurements. The angular dependency of the tensor asymmetries in deuteron photodisintegration is extracted for the first time.