Molecularly Imprinted Artificial Biointerface for an Enzyme-Free Glucose Transistor

Area of Science:

• Biosensor technology
• Materials science
• Analytical chemistry

Background:

• Versatile biosensors require selective and sensitive detection devices with artificial biointerfaces.
• Enzyme-free detection methods are desirable for simplified biosensor platforms.

Purpose of the Study:

• To develop a molecularly imprinted polymer (MIP)-coated gate field-effect transistor (FET) biosensor for enzyme-free, low-concentration glucose detection.
• To evaluate the sensitivity, selectivity, and stability of the developed biosensor for glucose in biological fluids.

Main Methods:

• Fabrication of a FET biosensor functionalized with a molecularly imprinted polymer (MIP) selective for glucose.
• Utilizing the change in molecular charge density upon glucose binding to vinylphenylboronic acid within the MIP.
• Characterization of sensor performance using Langmuir adsorption isotherm analysis and capacitance measurements.

Main Results:

• Achieved a low detection limit of 3 μM and high sensitivity of 115 mV/decade for glucose detection.
• Demonstrated a significantly enhanced binding stability constant (Ka = 1192 M⁻¹) for phenylboronic acid with glucose compared to non-electrical methods.
• Exhibited approximately 200-fold higher selectivity for glucose over fructose.

Conclusions:

• The MIP-coated gate FET biosensor provides a highly selective and sensitive platform for enzyme-free glucose detection.
• This approach offers a new strategy for designing versatile biosensing systems with improved performance.
• The developed biosensor is suitable for detecting low concentrations of glucose in biological fluid samples like tears.