Paper based colorimetric detection of miRNA-21 using Ag/Pt nanoclusters

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 227; p. 117529
• Main Authors: Fakhri, Neda, Abarghoei, Shima, Dadmehr, Mehdi, Hosseini, Morteza, Sabahi, Hossein, Ganjali, Mohammad Reza
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 15.02.2020
• Subjects: Cancer; Colorimetric; DNA-Ag/Pt nanoclusters; Paper based; Peroxidase; Paper based; Peroxidase; DNA-Ag/Pt nanoclusters; Colorimetric; Cancer
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2019.117529

Abnormal expression of MicroRNA-21 (miRNA-21) is considered to be a reliable biomarker for the early diagnosis of cancer. In this work, a novel paper based biosensor was fabricated to detect sub-micro molar concentrations of miRNA-21 based on peroxidase mimetic activity of DNA-templated Ag/Pt nanoclusters (DNA-Ag/Pt NCs), which could catalyze the reaction of hydrogen peroxide and 3,3′,5,5′ tetramethylbenzidine (TMB), to produce a blue color. The Mechanism of reaction was based on the inhibition effect of miRNA-21 on peroxidase-like activity of nanosensor which resulted to quantitative determination of miRNA-21 concentration. It was found that miRNA-21 could be linearly detected in the range from 1-700 pM (A652 = 0.16x-0.96, R2 = 0.99; x = -log [miRNA-21]) with a detection limit of 0.6 pM. Moreover, a paper assay was carried out on a Y-shaped paper-based microfluidic device in order to use the distinctive features of micro-channels such as short response time, very low reagent volume, low fabrication cost, etc. After performing paper based assay, a good linear range was observed between 10-1000 pM (y = 0.06x+147.48, R2 = 0.99; x = [miRNA-21]) with detection limit of 4.1 pM. The practical application of proposed method for detection of miRNA-21 in real sample was assayed in the human urine sample and indicated the colorimetric method had acceptable accuracy. [Display omitted] •A novel paper-based microfluidic sensor was designed for detection of miRNA-21.•The miRNA-21 detection mechanism is based on peroxidase mimetic activity of DNA-Ag/Pt NCs.•The color change was obvioused in different concentration of miRNA-21.•This strategy shows excellent selectivity toward miR-21.