An amperometric needle-type glucose sensor tested in rats and man

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Sensor Technology

Background:

• Accurate glucose monitoring is crucial for diabetes management.
• Existing continuous glucose monitoring (CGM) systems have limitations.
• Development of novel electrochemical sensors offers potential for improved glucose detection.

Purpose of the Study:

• To develop and evaluate a novel amperometric needle-type sensor for subcutaneous glucose measurement.
• To assess the sensor's performance in vivo in both animal models and human subjects.
• To determine the correlation, accuracy, and stability of the sensor's glucose readings.

Main Methods:

• Fabrication of a 25-gauge needle-type amperometric sensor using glucose oxidase and dimethyl ferrocene paste.
• Subcutaneous implantation of sensors in anesthetized rats and conscious human subjects.
• In vivo glucose level modulation using glucose and insulin infusion in rats, and glucose clamp technique in humans.
• Analysis of sensor current response, correlation with blood glucose, hysteresis, and phase-lag.

Main Results:

• The sensor demonstrated good correlation with blood glucose levels in both rats (median r=0.83) and humans (median r=0.80).
• Hysteresis and phase-lag were not significant issues, indicating reliable performance during glucose fluctuations.
• The sensor showed stable current response for up to 6.0 hours in rats and 4.5 hours in humans.

Conclusions:

• The developed amperometric needle-type sensor is a viable tool for subcutaneous glucose monitoring.
• The sensor exhibits promising accuracy and stability for in vivo glucose measurements.
• Further research may optimize sensor design and calibration for clinical applications.