Electrochemical capacitance-based aptasensor for HER2 detection

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Biosensor Technology

Background:

• Human Epidermal Growth Factor Receptor 2 (HER2) overexpression is linked to breast cancer proliferation and progression.
• HER2 is a potential biomarker in serum, but requires sensitive and simple detection platforms.
• Current detection methods may lack the required sensitivity or simplicity for widespread clinical application.

Purpose of the Study:

• To develop and optimize a highly sensitive electrochemical platform for HER2 detection.
• To create a simple, accurate biosensor for quantifying HER2 in biological samples.
• To explore the utility of DNA aptamers and ferrocene-modified electrodes for HER2 sensing.

Main Methods:

• Modification of a gold electrode surface with a self-assembled monolayer of DNA aptamer, ferrocenyl hexanethiol, and mercapto hexanethiol.
• Utilizing Electrochemical Impedance Spectroscopy (EIS) to analyze interfacial capacitance changes.
• Quantifying HER2 concentration by measuring electrochemical responses in Phosphate-Buffered Saline (PBS) and human serum.

Main Results:

• Achieved a limit of detection for HER2 as low as 3.61 pg/mL.
• Demonstrated a sensitivity of 12.28 nF per decade.
• Established a linear detection range from 1 pM to 1 µM in human serum.
• Successfully detected HER2 in undiluted human serum, highlighting its practical applicability.

Conclusions:

• The developed electrochemical aptasensor provides a simple and highly sensitive platform for HER2 detection.
• This platform shows significant potential as a biomarker for cancer presence and progression.
• The system is applicable for aptamer screening and studying biological interaction systems.