Modular probe-based colorimetric miRNA detection via polymerase/endonuclease assisted chain displacement

Area of Science:

• Biochemistry
• Molecular Biology
• Analytical Chemistry

Background:

• Accurate microRNA (miRNA) analysis is vital for research and clinical applications, including nursing strategies.
• Existing miRNA detection methods may lack sensitivity or specificity for certain applications.

Purpose of the Study:

• To develop a novel, highly sensitive, and specific colorimetric method for sequence-specific miRNA detection.
• To validate the method's performance for quantifying miRNA-21 in biological samples, such as serum.

Main Methods:

• A colorimetric technique utilizing a dumbbell probe-based polymerase/endonuclease assisted chain displacement reaction.
• Integration of silver ions (Ag+)-aptamer assisted color reaction for signal amplification.
• Validation using miRNA-21 as a target analyte in controlled solutions and human serum samples.

Main Results:

• The assay achieved precise quantification of miRNA-21 within a concentration range of 100 fM to 5 nM.
• A low limit of detection (LOD) of 45.32 fM was established for miRNA-21.
• The method demonstrated high specificity, capable of distinguishing single-nucleotide variations, and showed excellent agreement with a commercial miRNA detection kit in serum samples.

Conclusions:

• The developed colorimetric assay offers a sensitive, specific, and reliable method for miRNA-21 detection.
• This technique has potential applications in miRNA research and could aid in guiding nursing strategies through precise molecular diagnostics.
• The assay's performance in serum samples suggests its utility in clinical settings for biomarker analysis.