Simple and sensitive detection of miRNA-122 based on a micro-biosensor through square wave voltammetry

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biomedical Diagnostics

Background:

• Early detection of hepatocellular carcinoma (HCC) is critical for patient survival.
• MicroRNA-122 (miRNA-122) is a key biomarker for HCC diagnosis.
• Sensitive and simple detection methods for miRNA-122 in blood are needed.

Purpose of the Study:

• To develop a sensitive and selective micro-biosensor for detecting miRNA-122.
• To utilize a platinum microelectrode modified with molybdenum disulfide and gold nanoparticles (PtμE/MoS2/Au) for enhanced detection.
• To validate the micro-biosensor's performance in real blood samples for HCC diagnosis.

Main Methods:

• Fabrication of a PtμE/MoS2/Au micro-biosensor.
• Immobilization of a DNA probe complementary to miRNA-122 onto the sensor surface.
• Quantitative detection of miRNA-122 using square wave voltammetry with [Fe(CN)6]4-/3- as a mediator.

Main Results:

• The PtμE/MoS2/Au micro-biosensor exhibited a linear detection range for miRNA-122 from 10^-11 to 10^-8 M.
• A low detection limit of 1.6 × 10^-12 M was achieved.
• The biosensor demonstrated excellent selectivity, reproducibility, and successful application in real blood samples.

Conclusions:

• The developed PtμE/MoS2/Au micro-biosensor provides a highly sensitive and selective platform for miRNA-122 detection.
• This assay holds significant potential as a tool for early clinical diagnosis of HCC.
• The integration of nanomaterials and electrochemical techniques offers a promising approach for biomarker detection.