Microfabricated glucose biosensor for culture well operation

Area of Science:

• Biomedical Engineering
• Biosensor Technology
• Microfabrication

Background:

• Accurate glucose monitoring is crucial for understanding cellular metabolism.
• Existing methods often lack the throughput or sensitivity for real-time cell culture analysis.
• Development of integrated microbiosensors is needed for high-throughput screening.

Purpose of the Study:

• To develop and optimize a water-based carbon screen-printing ink for glucose microbiosensor fabrication.
• To integrate these microbiosensors into a 96-well microplate format for cell culture monitoring.
• To evaluate the performance and applicability of the developed microbiosensors.

Main Methods:

• Formulation of a carbon screen-printing ink with cobalt phthalocyanine (CoPC) and glucose oxidase (GOx).
• Fabrication of platinum (Pt) microelectrodes using microelectromechanical systems (MEMS) and screen-printing techniques.
• Testing of microbiosensor performance in buffer and cell culture medium, including optimization with collagen coating.
• Evaluation using a 5-channel multipotentiostat in a 96-well format.

Main Results:

• Satisfactory amperometric performance achieved with dip-coated and capillary-deposited inks on Pt electrodes.
• Optimal performance required Pt microdisc electrodes ≥100 μm; screen-printing on MEMS-fabricated pads was successful.
• Microbiosensors showed linearity up to 5 mM glucose in buffer (CV=6%) and up to 2 mM in culture medium with collagen coating (CV=5.7%).
• Observed correlation between amperometric response and cell number in microwells.

Conclusions:

• Successful integration of microphotolithography and screen-printing for creating glucose microbiosensors in a 96-well format.
• Developed microbiosensors are capable of monitoring glucose metabolism in real-time cell cultures.
• This technology holds potential for various applications in cell-based assays and drug discovery.