Signal-on fluorescence biosensor for microRNA-21 detection based on DNA strand displacement reaction and...

Area of Science:

• Biochemistry
• Molecular Biology
• Analytical Chemistry

Background:

• MicroRNAs are crucial in biological processes and serve as disease biomarkers.
• Sensitive, rapid, and selective microRNA detection is vital for early disease diagnosis and treatment.
• Current detection methods require improvement in sensitivity and selectivity.

Purpose of the Study:

• To develop a sensitive fluorescence assay for microRNA-21 detection.
• To utilize DNA polymerase and DNAzyme reactions for signal amplification.
• To establish a method applicable for analyzing microRNA-21 in clinical samples like serum.

Main Methods:

• Developed a fluorescence assay for microRNA-21 detection.
• Employed DNA polymerase-induced strand displacement amplification for trigger DNA production.
• Utilized Mg2+-dependent DNAzyme catalysis for signal DNA cleavage and fluorescence generation.
• Incorporated magnetic separation for efficient sample processing.

Main Results:

• Achieved high detection sensitivity with a low limit of detection of 0.27 fM.
• Demonstrated excellent detection specificity for microRNA-21.
• Successfully applied the assay to analyze microRNA-21 expression levels in human serum samples from cancer patients.

Conclusions:

• The developed fluorescence assay provides a sensitive and selective platform for microRNA-21 detection.
• This method holds promise for quantitative analysis in biomedical research and clinical diagnostics.
• The assay's ability to detect microRNA-21 in serum suggests its potential for early cancer diagnosis.