A novel signal amplification tag to develop rapid and sensitive aptamer-based biosensors

Area of Science:

• Biomarker Discovery
• Nanotechnology
• Electrochemical Biosensing

Background:

• MicroRNAs (miRNAs) are crucial blood-borne biomarkers, but their detection is analytically challenging.
• Existing methods face limitations due to the intrinsic characteristics of miRNAs.
• There is a need for sensitive and specific detection methods for clinical applications.

Purpose of the Study:

• To develop a novel electrochemical biosensor for sensitive miRNA detection.
• To synthesize and characterize blackberry-like magnetic DNA/FMMA nanospheres as signal amplification probes.
• To demonstrate the potential of the developed biosensor for early gastric cancer diagnosis.

Main Methods:

• Synthesis of magnetic DNA/FMMA nanospheres via hybridization chain reaction and RAFT polymerization.
• Immobilization of nanospheres on a gold stir-bar as signal probes.
• Development of a catalyzed hairpin assembly strategy for signal generation and magnetic enrichment.
• Electrochemical detection of miRNA-106a as a model target.

Main Results:

• The developed aptamer-based biosensor exhibited high specificity and selectivity for miRNA detection.
• The biosensor demonstrated acceptable storage stability and excellent performance in real samples without pretreatment.
• The novel nanosphere probes provided strong electrochemical signals through signal amplification.

Conclusions:

• The developed magnetic nanosphere-based electrochemical biosensor offers a promising platform for miRNA detection.
• This strategy has significant potential for the early diagnosis of gastric cancer.
• The biosensor can be utilized for the clinical monitoring of various miRNA sequences.