Glucose sensor membranes for mitigating the foreign body response

Area of Science:

• Biomedical Engineering
• Materials Science
• Immunology

Background:

• Continuous glucose monitoring (CGM) devices face limitations in longevity due to the foreign body response (FBR).
• FBR leads to biofouling, leukocyte infiltration, and fibrous encapsulation, impairing sensor function and integration.
• Current strategies often involve passive surface modifications, which have not fully resolved tissue integration issues.

Purpose of the Study:

• To review current strategies for mitigating the foreign body response (FBR) in continuous glucose monitoring (CGM) devices.
• To explore advanced approaches, particularly active release coatings, for enhancing sensor biocompatibility and in vivo performance.
• To identify methods for improving tissue integration and extending the functional lifetime of subcutaneous glucose biosensors.

Main Methods:

• Review of existing literature on FBR mitigation strategies for implantable biosensors.
• Analysis of passive coating approaches and their limitations in addressing FBR.
• Investigation of active release systems incorporating biological agents to modulate FBR and promote tissue integration.

Main Results:

• Passive coatings offer partial mitigation of FBR but do not achieve full sensor integration.
• Active release coatings, by delivering agents like VEGF, dexamethasone, or nitric oxide, show potential for directing FBR towards tissue integration.
• Combining active release with biocompatible materials presents a promising avenue for improving the in vivo performance of CGM sensors.

Conclusions:

• Active release strategies represent a significant advancement in managing the FBR for CGM devices.
• Enhanced biocompatibility through active modulation of the host response is key to improving sensor longevity.
• Future developments in active release coatings may overcome current limitations and extend the clinical utility of continuous glucose monitoring.