Nitric Oxide Release for Enhanced Biocompatibility and Analytical Performance of Implantable Electrochemical Sensors

The real-time, continuous monitoring of glucose/lactate, blood gases and electrolytes by implantable electrochemical sensors holds significant value for critically ill and diabetic patients. However, the wide-spread use of such devices has been seriously hampered by implant-initiated host responses (e. g., thrombus formation, inflammatory responses and bacterial infection) when sensors are implanted in blood or tissue. As a result, the accuracy and usable lifetime of in vivo sensors are often compromised. Nitric oxide (NO) is an endogenous gas molecule able to inhibit platelet adhesion/activation, inflammatory responses and bacterial growth. As such, the release of NO from the surfaces of in vivo sensors is a promising strategy for enhancement of their biocompatibility and analytical performance. In this review, the physiological functions of NO to improve the biocompatibility of implantable electrochemical sensors are introduced, followed by a brief analysis of chemical approaches to realize NO release from such devices. A detailed summary of the various types of NO releasing electrochemical sensors reported to date and their performance in benchtop and/or in vivo testing are also provided. Finally, the prospects of future developments to further advance NO releasing sensor technology for clinical use are discussed.

Automated summary

This review introduces the physiological functions of NO to improve the biocompatibility of implantable electrochemical sensors, as well as provides a detailed summary of various types of NO releasing sensors and their performance in benchtop and/or in vivo testing. Discussions on prospects of future developments in NO releasing sensor technology for clinical use are also presented.