Highly sensitive dual mode electrochemical platform for microRNA detection.
MicroRNAs (miRNAs) play crucial regulatory roles in various human diseases including cancer, making them promising biomarkers. However, given the low levels of miRNAs present in blood, their use as cancer biomarkers requires the development of simple and effective analytical methods. Herein, we report the development of a highly sensitive dual mode electrochemical platform for the detection of microRNAs. The platform was developed using peptide nucleic acids as probes on gold electrode surfaces to capture target miRNAs. A simple amplification strategy using gold nanoparticles has been employed exploiting the inherent charges of the nucleic acids. Electrochemical impedance spectroscopy was used to monitor the changes in capacitance upon any binding event, without the need for any redox markers. By using thiolated ferrocene, a complementary detection mode on the same sensor was developed where the increasing peaks of ferrocene were recorded using square wave voltammetry with increasing miRNA concentration. This dual-mode approach allows detection of miRNA with a limit of detection of 0.37 fM and a wide dynamic range from 1 fM to 100 nM along with clear distinction from mismatched target miRNA sequences. The electrochemical platform developed can be easily expanded to other miRNA/DNA detection along with the development of microarray platforms.
Department of Electronic &Electrical Engineering, University of Bath, Bath BA2 7AY, United Kingdom.
Pawan
P
Jolly
Department of Physics, University of São Paulo, 14040-901, Ribeirão Preto, SP, Brazil.
Marina R
MR
Batistuti
Department of Electronic &Electrical Engineering, University of Bath, Bath BA2 7AY, United Kingdom.
Anna
A
Miodek
Department of Electronic &Electrical Engineering, University of Bath, Bath BA2 7AY, United Kingdom.
Pavel
P
Zhurauski
Department of Physics, University of São Paulo, 14040-901, Ribeirão Preto, SP, Brazil.
Marcelo
M
Mulato
Department of Pharmacy &Pharmacology, University of Bath, Bath BA2 7AY, United Kingdom.
Mark A
MA
Lindsay
Department of Electronic &Electrical Engineering, University of Bath, Bath BA2 7AY, United Kingdom.
Pedro
P
Estrela
D015374:Biosensing Techniques; D017097:Electric Impedance; D055664:Electrochemical Techniques; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry; D035683:MicroRNAs / Q000032:analysis*; D020135:Peptide Nucleic Acids / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D015203:Reproducibility of Results; D013499:Surface Properties
D035683:MicroRNAs; D020135:Peptide Nucleic Acids; D012333:RNA, Messenger; D006046:Gold