Sensitive Detection of Motor Neuron Disease Derived Exosomal miRNA Using Electrocatalytic Activity of Gold-Loaded Superparamagnetic Ferric Oxide Nanocubes
RIS ID
145335
Abstract
© 2020 Wiley-VCH GmbH Dysregulated microRNA associated pathways contribute to the pathology of neurological disorders, hence presenting themselves as a potential candidate for motor neuron disease (MND) diagnosis. Herein, we reported an enzymatic amplification-free approach for the electrochemical detection of exosomal microRNA (miR-338-3p) from preconditioned media of motor neurons obtained from amyotrophic lateral sclerosis (ALS) patients and healthy controls. Our assay utilizes a three-step strategy that involves i) initial isolation and purification of exosomal miR-338-3p from patients and healthy controls using biotinylated complementary capture probe followed by heat-release of the specific target, ii) direct adsorption of target miR-338-3p onto the gold-loaded ferric oxide nanocatalyst (AuNP-Fe2O3NC) through affinity interaction between microRNA and exposed gold surfaces within the AuNP-Fe2O3NC, and iii) gold nanocatalyst-induced electrocatalytic signal amplification through methylene blue-ferricyanide redox cycling (MB/[Fe(CN)6]3−). The electrocatalytic signal is monitored by using chronocoulometry at the AuNP–Fe2O3NC-modified screen-printed carbon electrode (AuNP-Fe2O3NC/SPCE). We demonstrated the detection of miR-338-3p as low as 100 aM in spiked buffer samples with a relative standard deviation of (%RSD) <5.0 % (n=5). We also demonstrate the successful detection of miR-338-3p from a small cohort of preconditioned media of motor neurons obtained from ALS patients and healthy controls. The sensor avoids the use of conventional recognition and transduction layers in hybridization-based electrochemical miRNA biosensors, polymerase-based amplifications. It is robust, fast (<2.5 h) and potentially applicable to a wide variety of RNA biomarker detection.
Publication Details
Masud, M., Mahmudunnabi, R., Aziz, N., Stevens, C., Do-Ha, P., Yang, S., Blair, I., Hossain, M. A., Shim, Y., Ooi, L., Yamauchi, Y. & Shiddiky, M. (2020). Sensitive Detection of Motor Neuron Disease Derived Exosomal miRNA Using Electrocatalytic Activity of Gold-Loaded Superparamagnetic Ferric Oxide Nanocubes. ChemElectroChem, 7 (16), 3459-3467.