Detection of Micro RNA-210 Using Optical Biosensing Platform Based on the Actuation of Discrete Gold Nanoparticle Dimers

Abstract

In recent medical development and research, people have been challenged on detection of biomarker in diseases via a ready and cost-effective method at early stage of diseases. Micro RNA-210 (miRNA-210) is well known as a sensor for hypoxia as the level of miRNA-210 typically rises in response to low oxygen tension in various cell types. Detection of the level of miRNA-210 during pregnancy could potentially prevent pregnancy-related disorders, such as Pre-Eclampsia. The purpose of this project is to achieve a detection of miRNA-210 using a sensing platform based on the actuation of discrete gold nanoparticle dimers. This sensing platform has been established for the detection of short oligonucleotides, such as single-stranded DNA. The optical response is achieved via a geometrical extension of the dimers upon binding of analyte. The detection signal is a spectral blue shift in the hybridized plasmon mode as measured via single nanostructure scattering spectroscopy. We applied this optical biosensing mechanism to the detection of miRNA-210 in our project. Our experimental results show a spectral blue shift when the dimers were exposed to miRNA-210, which is evidence of successful detection of miRNA-210. The magnitude of this shift was gradually improved by optimizing experimental conditions, including changing salt concentration, buffer type, and incubation time of analyte. In addition, the calibration curve and detection limit of miRNA-210 were also studied. To conclude, our project demonstrates an optical biosensing platform for the detection of miRNA-210 with ultralow detection limits and ability to differentiate interfering molecules, which offers a promising future for prevention of pregnancy-related disorders.