ASPECTS OF ENERGY EFFICIENCY IN THE HOUSING AND COMMUNAL SERVICES OF THE MODERN METROPOLIS

Energy efficiency means using the production facilities or systems less energy to achieve performance indicators or even their improvement compared with the usual facilities and systems. Energy saving in housing and utilities complex of legal, organizational, scientific, technical and economic measures aimed at the rational use of fuel and energy resources in the housing sector, to reduce energy costs on the maintenance of housing facilities. The article discusses the main activities aimed at improving energy efficiency in housing.Энергоэффективность подразумевает использование производствами или системами меньше энергоресурсов для достижения показателей производительности или даже их улучшения по сравнению с обычными производствами и системами. Энергосбережение в ЖКХ – комплекс правовых, организационных, научных, производственных, технических и экономических мер, направленных на рациональное использование топливно-энергетических ресурсов в жилищно-коммунальной сфере, на снижение энергозатрат на содержание объектов ЖКХ. В статье будут рассмотрены основные мероприятия, направленные на повышение энрегоэффективности в ЖКХ.Сборник выпущен при поддержке Фонда содействия развитию УрФУ имени первого Президента России Б.Н. Ельцин

Improvement of Seed-Mediated Growth of Gold Nanoparticle Labels for DNA Membrane-Based Assays

Gold nanoparticles (AuNPs) are popular labels for colorimetric detection of various analytes, involving proteins, nucleic acids, viruses, and whole cells because of their outstanding optical properties, inertness, and modification variability. In this work, we present an improved approach for enhancement of color intensity for DNA membrane microarrays based on seed-mediated growth of AuNP labels. Biotin-labeled DNA is hybridized with capture oligonucleotide probes immobilized on the microarrays. Then biotin is revealed by a streptavidin–AuNP conjugate followed by the detection of AuNPs. Optimization of seed-mediated enlargement of AuNPs by the reduction of tetrachloroauric acid with hydroxylamine made it possible to change the coloring of specific spots on the microarrays from pink to a more contrasting black with minor background staining. Mean size of the resulting AuNPs was four times larger than before the enhancement. Adjusting the pH of HAuCl4 solution to 3.5 and use of a large excess of hydroxylamine increased the signal/background ratio by several times. The method’s applicability was demonstrated for quantification of a short oligonucleotide of 19 bases and full-length TEM-type β-lactamase genes of 860 bp responsible for the development of bacterial resistance against β-lactam antibiotics. Improved protocol for AuNP enlargement may be further transferred to any other membrane-based assays of nucleic acids with both instrumental and visual colorimetric detection

Multiplex Digital Quantification of β-Lactamase Genes in Antibiotic-Resistant Bacteria by Counting Gold Nanoparticle Labels on Silicon Microchips

Digital quantification based on counting of individual molecules is a promising approach for different biomedical applications due to its enhanced sensitivity. Here, we present a method for the digital detection of nucleic acids (DNA and RNA) on silicon microchips based on the counting of gold nanoparticles (GNPs) in DNA duplexes by scanning electron microscopy (SEM). Biotin-labeled DNA is hybridized with capture oligonucleotide probes immobilized on the microchips. Then biotin is revealed by a streptavidin–GNP conjugate followed by the detection of GNPs. Sharp images of each nanoparticle allow the visualization of hybridization results on a single-molecule level. The technique was shown to provide highly sensitive quantification of both short oligonucleotide and long double-strand DNA sequences up to 800 bp. The lowest limit of detection of 0.04 pM was determined for short 19-mer oligonucleotide. The method’s applicability was demonstrated for the multiplex quantification of several β-lactamase genes responsible for the development of bacterial resistance against β-lactam antibiotics. Determination of nucleic acids is effective for both specific DNA in lysates and mRNA in transcripts. The method is also characterized by high selectivity for single-nucleotide polymorphism discrimination. The proposed principle of digital quantification is a perspective for studying the mechanisms of bacterial antibiotic resistance and bacterial response to drugs