An Annexin V-based biosensor for quantitatively detecting early apoptotic cells

Area of Science:

• Biomedical Engineering
• Biosensor Technology
• Cell Biology

Background:

• Apoptosis is a critical cellular process implicated in various diseases.
• Early detection of apoptotic cells is vital for disease diagnosis and treatment monitoring.
• Current detection methods can be time-consuming or lack sensitivity.

Purpose of the Study:

• To develop a novel electrochemical biosensor for the sensitive detection of early apoptotic cells.
• To utilize the specific interaction between Annexin V and phosphatidylserine for biosensing.
• To evaluate the biosensor's performance in detecting cell apoptosis and for drug screening applications.

Main Methods:

• Immobilization of Annexin V onto a gold nanoparticle-modified electrode surface.
• Detection of early apoptotic cells via electrochemical impedance spectroscopy (EIS).
• Validation using a model system (phosphatidylserine-modified liposomes) and real cells induced by 5-fluorouracil.

Main Results:

• The biosensor demonstrated stable and high loading of Annexin V, enhancing sensitivity.
• Increased phosphatidylserine exposure on early apoptotic cells led to strong electrode surface interaction.
• The biosensor showed high potential for rapid detection of cell apoptosis and drug screening.
• Results were consistent with traditional methods like fluorescence microscopy and flow cytometry.

Conclusions:

• A novel electrochemical biosensor based on Annexin V and phosphatidylserine interaction was successfully developed.
• The biosensor provides a sensitive and rapid method for detecting early apoptotic cells.
• This technology holds promise for applications in drug screening and disease diagnostics.