Biomedical subjects

A M Egorov

Publications and source records attributed to A M Egorov.

152 records · Page 9Linked to original sources

PubMedDate not supplied

[Conversion of D-glucose into D-fructose in a column reactor with immobilized glucose isomerase].

Conversion of D-glucose into D-fructose in a column reactor of a continuous type was studied using an immobilized enzyme, glucose isomerase from Actinomyces olivocinereus. The effective parameters of Km, Vmax, energy activation at various flow rates were calculated. During 32 days of continuous operation the enzyme activity fell down to 84% of the initial level. A system of recirculation was employed to use immobilized glucose isomerase with a low activity.

Actinomyces↗

PubMedDate not supplied

[Polarized immunofluorescent analysis of the herbicide isoproturon].

Polarographic fluoroimmunoassay was developed for estimation of residual amounts of the herbicide isoproturon . The procedure is simple, accurate, highly sensitive and allows 10 preparations to be tested within approximately 7 min; the sample volume was 50 microliters and the low limit of the procedure sensitivity was about 0.2 micrograms/ml. The polarographic immunoassay may be used in screening express controls of isoproturon concentration in the sewage or in various extracts from various sources to control the herbicide contamination.

Fluorescence Polarization Immunoassay↗

PubMedDate not supplied

[Polarization fluoroimmunoassay of progesterone].

A quick reliable homogeneous polarization fluoroimmunoassay (PFIA) of progesterone was developed. The assay is carried out with Abbott TDx (USA) polarization fluorometer and it takes 5-7 min to analyze 10 samples by this method. The range of progesterone concentrations determined is 1 to 1000 ng/ml. Fluorescein labeled progesterone-3-carboxymethyloxime which was used as tracer (labeled antigen) during analysis has been synthesized and purified. Two types of PFIA were developed: one making use of rabbit antiserum to progesterone-3-carboxymethyloxime conjugated with bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH), in the other antiserum to progesterone-11-hemisuccinate-BSA (or KLH) is used. Different combinations of the tracer and antibodies were used. The sensitivity of heterologous PFIA (with antibodies to immunogen heterologous to tracer by structure) was higher than that of homologous PFIA. The test is sufficiently sensitive and specific. The method is particularly valuable for determination of progesterone in model solutions (using buffer standards).

Animals↗

PubMedDate not supplied

[Polarization fluorescence immunoanalysis of herbicides of the S-1,3,5-triazine class].

Polarization fluoroimmunoassay for s-triazine herbicides was developed. The sensitive of assay is higher with using shortest chemical "bridge" length between the molecule of antigen and fluorescent label. The detection limit of atrazine in 50 microL sample was 6 ng/ml. The total time required for an assay of 10 samples was 6 ng/ml. The total time required for an assay of 10 samples is approximately 7 min. The method may be used for environmental monitoring of s-triazine herbicides in water samples.

Environmental Monitoring↗

PubMedDate not supplied

[Development of a method of polarization fluorescence immunoanalysis of the herbicide 2,4,5-trichlorophenoxyacetic acid].

Immunoreagents were produced and a polarographic fluorescent immunoassay was developed for estimation of residual content of widely used herbicide 2,4,5-trichlorophenoxy acetic acid. The procedure is simple, accurate, specific and allowed one to measure 10 preparations within 7 min. The sample volume was 50 microliters and the minimal content of the substance estimated was 0.5 microgram/ml. This procedure may be used in screening quick tests of the herbicide concentration in sewage or in extracts from various sources.

2,4,5-Trichlorophenoxyacetic Acid↗

PubMedDate not supplied

[Polarized fluoroimmunoanalysis of phenobarbital using the TD(x) analyzer from "Abbott" laboratories].

Polarographic fluoroimmunoassay was developed for identification and estimation of phenobarbital in urine. The study was carried out using TDx-analyzer "Abbott" (USA) under conditions of automatic service by modified program N 21 intended for analysis of kanamycin. In the procedure developed rabbit antiserum against phenobarbital was used at the initial dilution 1:2 and the tracer 5-ethyl-5-(4'-fluoroscein thiocarbamyl aminophenyl)barbituric acid was applied at the initial concentration of 60 nmol/l. The minimal content of phenobarbital evaluated in urine was as small as 0.09 microgram/ml and it was measured in the limits of 0.5 microgram/ml. Specificity of the analysis and its reproducibility were studied. The results of the polarographic fluoroimmunoassay correlated highly to the data of EMIT-st-assay and HPLC.

Animals↗

PubMedDate not supplied

[Joint immobilization of L-lysine-alpha-oxidase and peroxidase on porous membrane carriers].

The goal of the present study was the development of the optimal method of co-immobilization of two enzymes: L-lysine alpha-oxidase from Trichoderma sp. and horseradish peroxidase. Commercial nitrocellulose, nylon and N+ nylon membranes were used as carriers. The immobilization was carried out either by absorbtion or by covalent binding with aldehyde groups. The aldehyde groups were attached to the surface of the carriers by UV-irradiation of membranes in the presence of p-azidotetrafluorobenzaldehyde. The optimal concentrations of reagents, enzymes and reaction conditions were found. The membranes with the co-immobilised L-lysine alpha-oxidase and peroxidase were shown to be useful for the determination of L-lysine concentrations.

Amino Acid Oxidoreductases↗

PubMedDate not supplied

[Solid-phase immunoenzyme analysis of chloramphenicol in human blood serum].

The method of enzyme linked immunosorbent assay (ELISA) for quantitative detection of chloramphenicol (CAP) in human blood serum was developed. Peculiarities of the adsorption on the microtitre plates surface of CAP-ovalbumin conjugate were investigated. Different conditions of competition stage of the analysis were studied. Conditions providing CAP monitoring in human blood serum in the clinical range were optimized. Matrix effect on the assay results was studied. The specificity of the analytical system was investigated and the reagents stability was examined. The method developed permits CAP concentration to be determined in human blood serum, diluted 1/100, in the linear range from 10 to 1000 ng/ml. The assay is characterized by high sensitivity (1 ng/mL) and good reproducibility (CV < 12%), assay time is about 3 hours.

Chloramphenicol↗