Vitamin B₁₂-catalyzed electro-polymerization for ultrasensitive RNA detection

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Materials Science

Background:

• Lung cancer early detection remains a challenge, necessitating sensitive biomarker identification.
• MicroRNA-21 (miRNA-21) is a key biomarker for lung cancer.
• Electrochemical biosensors offer potential for sensitive and rapid biomarker detection.

Purpose of the Study:

• To develop a highly sensitive electrochemical biosensor for the early detection of lung cancer biomarker miRNA-21.
• To utilize vitamin B12 as a natural catalyst for atom transfer radical polymerization (ATRP) in biosensing.
• To achieve femtomolar level sensitivity for miRNA-21 detection.

Main Methods:

• Electrode modification with hairpin DNA containing an N3 end group.
• Click reaction for attaching the N3 group to an ATRP initiator upon miRNA-21 binding.
• Electrochemical atom transfer radical polymerization (eATRP) of FerrocenylMethyl Methacrylate (FcMMA) for signal amplification.
• Square wave voltammetry (SWV) for signal detection.

Main Results:

• The developed biosensor demonstrated high sensitivity for miRNA-21 detection, with a limit of detection (LOD) as low as 1.010 fM.
• The vitamin B12-catalyzed eATRP significantly amplified the electrochemical signal.
• The biosensor exhibited excellent selectivity and suitability for detecting RNA in complex biological samples.

Conclusions:

• The vitamin B12-based electrochemical biosensor provides a highly sensitive and selective platform for early lung cancer screening via miRNA-21 detection.
• The eATRP approach offers a powerful signal amplification strategy for ultra-sensitive RNA detection.
• This method holds promise for clinical applications in early cancer diagnosis.