Label-free biomolecular detection at electrically displaced liquid interfaces using interfacial electrokinetic...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Microfluidics

Background:

• Biosensors rely on biorecognition and signal transduction for analyte detection.
• Traditional biosensing transducers face challenges in cost-effectiveness and portability for point-of-care applications.
• Novel transducer development is crucial for accessible diagnostics.

Purpose of the Study:

• To develop a novel electrokinetic liquid biosensing method for sensitive, label-free analyte detection.
• To demonstrate a low-cost, portable biosensing strategy for point-of-care diagnostics.
• To utilize microfluidic-generated electrical interfaces as signal transducers.

Main Methods:

• A microfluidic system generating an electrical liquid interface was employed.
• An alternating current electrical field was applied to induce interface motion.
• The motion of the interface was measured to detect a model biomolecule (avidin).

Main Results:

• The electrokinetic biosensing method achieved sensitive, label-free detection of avidin.
• Femtomolar concentrations of avidin were detected in solution.
• The method demonstrated specificity against a background of serum protein.
• No surface functionalization or fluorescent labels were required.

Conclusions:

• The electric field-induced motion of microfluidic liquid interfaces serves as a sensitive and specific biosensing transducer.
• This novel strategy offers a promising low-cost, label-free approach for portable biomarker detection.
• The method has significant potential for point-of-care diagnostic applications.