Disposable 3D GNAs/AuNPs DNA-Circuit Strip for miRNAs Dynamic Quantification

Area of Science:

• Biosensing
• Nanotechnology
• Analytical Chemistry

Background:

• MicroRNA (miRNA) detection is crucial for disease diagnosis and therapy.
• Existing methods for miRNA monitoring can be time-consuming and lack sensitivity.
• Developing rapid, real-time, and highly sensitive miRNA detection platforms is essential.

Purpose of the Study:

• To develop a dynamic, sensitive, and real-time biosensor for miRNA analysis.
• To utilize a 3D graphene nanoarray/gold nanoparticle (GNAs/AuNPs) carbon paper (CP) electrode for enhanced sensing.
• To validate the sensor's performance for specific miRNA detection and clinical sample analysis.

Main Methods:

• Fabrication of a 3D electrode by growing GNAs on CP and electrodepositing AuNPs.
• Real-time quantitative monitoring of microRNA-21 (miR-21) using cyclic voltammetry.
• Simultaneous detection of miR-21 and miR-155 using the developed DNA-circuit strip.
• Comparison of sensor results with quantitative reverse transcription PCR (qRT-PCR) for clinical samples.

Main Results:

• The 3D GNAs/AuNPs/CP electrode provides a large surface area, good conductivity, and biocompatibility.
• Dynamic quantitative monitoring of miR-21 was achieved within 16 minutes.
• Ultrasensitive detection limits for miR-21 and miR-155 were as low as 21.4 and 30.3 am, respectively.
• The sensor demonstrated comparable results to qRT-PCR for clinical samples, indicating high reliability.

Conclusions:

• The developed DSN-coupled GNAs/AuNPs/CP electrode enables rapid, sensitive, and real-time miRNA detection.
• The 3D structure enhances biomolecule hybridization and biosensor sensitivity.
• This disposable DNA-circuit strip holds significant promise for point-of-care clinical analysis of multiple low-concentration biomarkers.