Portable potentiometric device for determining the antioxidant capacity

Received: 25.11.22. Revised: 12.12.22. Accepted: 12.12.22. Available online: 21.12.22.The open microcell and the microfluidic device were developed for the determination of the antioxidants capacity of various objects.The potentiometric method implemented in the devices allows estimating the AOC of model and multicomponent objects.The relative standard deviation of the AOC in the devices did not exceed 10%.At present, the development of portable devices for the express assessment of the content of biologically active objects, such as antioxidants, is one of the relevant technological problems of modern chemistry, medicine, and engineering. The main advantages of such devices are the simplicity and rapidity of analysis, small volumes of analyte, as well as miniaturization of equipment, making it possible to carry out the on-site analysis and, thus, to take a step towards the personalized medicine. The potentiometric method using the K3[Fe(CN)6]/K4[Fe(CN)6] system, which in the laboratory-scale version proved to be the most accurate, reproducible, and express, was the basis for the developed prototypes of portable devices. In this study, two versions of prototypes of the portable device are proposed, namely, the open microcell with the 0.2 ml volume and the microfluidic device with flow control. The correctness of the antioxidant capacity (AOC) determination in both systems was confirmed by comparing the results of the "introduced-found" method on model solutions of antioxidants and their mixtures with the AOC results obtained in a standard laboratory electrochemical cell. The relative standard deviation did not exceed 10%. The AOC of some beverage industry was determined using the microfluidic device. The correlation coefficient of the results, obtained in the microfluidic device and the laboratory cell, was 0.90, which indicates good data convergence and the possibility of using the potentiometric method implemented in the microfluidic device to assess the AOC of multicomponent objects.The research funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged

Electrochemical creatinine determination with metal-organic framework catalyst based on copper and acetylenedicarboxylic acid

Fast and accurate determination of creatinine is critical in kidney function diagnostics. This paper discusses the usage of the metal-organic framework based on copper(II) and acetylenedicarboxylic acid (CuADCA) as a catalyst of electrochemical oxidation of creatinine, glucose and urea. CuADCA was synthesized by deprotonation with triethylamine for the first time. Successful synthesis was confirmed by FTIR and EDS. The material was characterized by SEM, EIS, and CV. CuADCA forms laminated-like flakes with diameter from 1 µm to 20 µm, which is consistent with the polymer-like structure. CV and EIS analyses showed that CuADCA immobilized on GCE acts as a catalyst in electrooxidation reaction of glucose, urea, and creatinine. The sensitivity of creatinine detection, 1057±99 µA/mM, was higher than the detection sensitivity of glucose and urea by more than 100 times with the limit of detection of 2 µM, so CuADCA is a promising material for further development of enzymeless sensors for creatinine

Using cloud infrastructure to facilitate data collection and conversion of HLA diagnostic data for the 18th International HLA and Immunogenetics Workshop

The International HLA and Immunogenetics Workshop (IHIW) is a recurring gathering of researchers, technologists and clinicians where participants contribute to collaborative projects with a variety of goals, and come to consensus on definitions and standards for representing HLA and immunogenic determinants. The collaborative and international nature of these workshops, combined with the multifaceted goals of several specific workshop components, necessitates the collection and curation of a wide assortment of data, as well as an adaptable platform for export and analysis. With the aim of ensuring data quality and creation of reusable datasets, specific standards and nomenclature conventions are continuously being developed, and are an integral part of IHIW. Here we present the 18th IHIW Database, a purpose-built and extensible cloud-based file repository and web application for collecting and analyzing project-specific data. This platform is based on open-source software and uses established HLA data standards and web technologies to facilitate de-centralized data repository ownership, reduce duplicated efforts, and promote continuity for future IHIWs

ELECTROCATALYTIC PROPERTIES OF PALLADIUM (II) ORGANIC COMPLEXES IN THE NESPHERE ELECTROCHEMICAL OXIDATION OF GLUCOSE

The aim of this work was to study the electrocatalytic properties of palladium (II) com-plexes immobilized on the surface of a working electrode in a neutral medium in relation to the electrochemical oxidation of glucose.Работа выполнена при финансовой поддержке Российского Научного Фонда (проект № 20-13-00142)

TECHNOLOGY OF PREPARING CONJUGATES OF MAGNETITE NANOPARTICLES WITH ANTIBODY CONJUGATES FOR QUANTITATIVE DETERMINATION OF MEASLES VIRUS ANTIGEN BY ELECTROCHEMICAL IMMUNOASSAY

The present work is devoted to development of approach for the determination of antigens of viruses, which consist in producing an electrochemical signal from the immunocomplex "target analyte (antigen) - conjugate antibodies and nanoparticles Fe3O4», localized on the surface of the electrode. Amino modified nanoparticles magnetite and their conjugates with measles virus antibodies were synthesizedin order to implement the approach

Clinical aspects of short-chain acyl-CoA dehydrogenase deficiency

Short-chain acyl-CoA dehydrogenase deficiency (SCADD) is an autosomal recessive inborn error of mitochondrial fatty acid oxidation. SCADD is biochemically characterized by increased C4-carnitine in plasma and ethylmalonic acid in urine. The diagnosis of SCADD is confirmed by DNA analysis showing SCAD gene mutations and/or variants. SCAD gene variants are present in homozygous form in approximately 6% of the general population and considered to confer susceptibility to development of clinical disease. Clinically, SCADD generally appears to present early in life and to be most frequently associated with developmental delay, hypotonia, epilepsy, behavioral disorders, and hypoglycemia. However, these symptoms often ameliorate and even disappear spontaneously during follow-up and were found to be unrelated to the SCAD genotype. In addition, in some cases, symptoms initially attributed to SCADD could later be explained by other causes. Finally, SCADD relatives of SCADD patients as well as almost all SCADD individuals diagnosed by neonatal screening remained asymptomatic during follow-up. This potential lack of clinical consequences of SCADD has several implications. First, the diagnosis of SCADD should never preclude extension of the diagnostic workup for other potential causes of the observed symptoms. Second, patients and parents should be clearly informed about the potential lack of relevance of the disorder to avoid unfounded anxiety. Furthermore, to date, SCADD is not an optimal candidate for inclusion in newborn screening programs. More studies are needed to fully establish the relevance of SCADD and solve the question as to whether SCADD is involved in a multifactorial disease or represents a nondisease

STRUCTURING OF THE SENSOR RECEPTOR LAYER TO CHLORAMPHENICOL BY ELECTRODEPOSITION OF 3,6-BIS(ETHYNYL)-9Н-CARBAZOLE

In this work, the approach to structuring the receptor layer of the glassy carbon electrode by electropolymerization of 3,6-bis(ethynyl)-9H-carbazole through the acetylene fragment has been proposed. The use of immobilized molecule as an agent for selective detection of chloramphenicol was evaluated.Работа выполнена при финансовой поддержке гранта МК-392.2022.1.3

FIP1/RCP Binding to Golgin-97 Regulates Retrograde Transport from Recycling Endosomes to the trans-Golgi Network

This study shows that Rab11 and its binding protein FIP1 are required for retrograde delivery of TGN38 and Shiga toxin from early/recycling endosomes to the TGN. We also demonstrate that Golgin-97 as a FIP1-binding protein and that this binding regulates the targeting of retrograde transport vesicles to the TGN

GIS and spatial data analysis: Converging perspectives

We take as our starting point the state of geographic information systems (GIS) and spatial data analysis 50 years ago when regional science emerged as a new field of enquiry. In the late 1950s and 1960s advances in computing technology were making possible forms of automated cartography that in due course would lead to th