Microfluidic Electrochemical Glucose Biosensor with In Situ Enzyme Immobilization
Nina Lokar1, Borut Pečar1, Matej Možek1
1Laboratory of Microsensor Structures and Electronics, Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, 1000 Ljubljana, Slovenia.
Biosensors
|March 29, 2023
Summary
This study presents a microfluidic electrochemical glucose biosensor using PQQ-GdhB enzyme immobilization. The developed biosensor offers a sensitive and reliable method for continuous glucose monitoring.
Area of Science:
- Electrochemistry
- Biosensor Technology
- Microfluidics
Background:
- Development of sensitive and reliable glucose biosensors is crucial for diabetes management.
- Microfluidic platforms offer advantages for integrated and miniaturized analytical devices.
Purpose of the Study:
- To develop and characterize a novel microfluidic electrochemical glucose biosensor.
- To investigate the in situ enzyme immobilization technique for enhanced biosensor performance.
Main Methods:
- Fabrication of thin-film metal electrodes on a glass substrate.
- In situ immobilization of pyrroloquinoline quinone-glucose dehydrogenase (PQQ-GdhB) enzyme using microcontact printing.
- Integration of microfluidic channels in polydimethylsiloxane (PDMS).
- Electrochemical characterization using cyclic voltammetry and chronoamperometry.
Main Results:
- The biosensor demonstrated a linear range up to 200 μM and a measurement range up to 10 mM glucose.
- A low detection limit of 30 µM glucose was achieved.
- Sensitivities of 0.79 nA/µM/mm² (with flow) and 0.61 nA/µM/mm² (without flow) were obtained at 20 µL/min.
Conclusions:
- The developed microfluidic glucose biosensor with in situ enzyme immobilization shows promising performance.
- This approach facilitates continuous and time-independent glucose detection.
- The methodology is applicable to a wide range of microfluidic biosensor development.
