Design and fabrication of nanomaterial-based analytical system for nucleic acid detection in microfluidic chip

Abstract

Abstract Introduction: Cardiovascular diseases are the main cause of death worldwide (1). During the past few decades, coronary artery disease and myocardial infarction have been the leading cause of death in industrialized countries, but during this time, with more and more knowledge of risk factors and better control of them in people with these factors, the age of developing coronary artery disease Coronary diseases and especially acute heart attacks have increased in such countries (2). Mortality of cardiovascular diseases is decreasing in developed countries, but the share of cardiovascular diseases among the factors leading to death is increasing in developing countries. Therefore, the factors involved in this disease are of great diagnostic importance for the control and treatment of the disease. objective: The aim of this study was the initial design and construction of a colorimetric sensor for the detection of miRNA499 based on a microfluidic chip using core-shell, gold-iron nanoparticles. materials and methods: The intensity of the received fluorescence light was observed and read with the help of a fluorescence plate reader equipped with a slide reader. By measuring the intensity of fluorescence generated in different concentrations of the target, it was possible to draw calibration curves for the concentration measurement of the desired target sequence, as well as to report the LOD and LOQ of the developed diagnostic method. Results and discussion: The identification method was based on designing and manufacturing the chip and with the help of a DNA probe fixed on magnetic nanoparticles of iron-gold shell core. The results of the analysis of the synthesized magnetic nanoparticles showed that the size of the nanoparticles is in the range of 192 nm.

Conclusion: The design and construction of the nanobiosensor used in this study was based on creating a fluorescence signal through the hybridization between the molecular probe of the nanobeacon and the target miRNA. Iron-gold core-shell nanoparticles were used for two purposes. Due to its magnetic core, a suitable accumulation of nanoparticles was created next to the magnet embedded in the detection area on the chip, which increases the detection sensitivity. Also, the nanoparticle gold shell can have a suitable quenching property for Beacon's molecular probe.