Metabolic biofouling of glucose sensors in vivo: role of tissue microhemorrhages

• Published in: Journal of diabetes science and technology Vol. 5; no. 3; pp. 583 - 595
• Main Authors: Klueh, Ulrike, Liu, Zenghe, Feldman, Ben, Henning, Timothy P, Cho, Brian, Ouyang, Tianmei, Kreutzer, Don
• Format: Journal Article
• Language: English
• Published: United States Diabetes Technology Society 01.05.2011
• Series: Interstitial Fluid Physiology as It Relates to Glucose Monitoring Technologies
• Subjects: Animals; Biofouling; Biosensing Techniques - methods; Blood Coagulation; Blood Glucose - analysis; Blood Glucose - metabolism; Blood Glucose Self-Monitoring - methods; Disease Models, Animal; Equipment Design; Female; Hemorrhage - physiopathology; Humans; Mice; Mice, Inbred ICR; Prostheses and Implants; Sensitivity and Specificity; Symposium; Time Factors
• ISSN: 1932-2968; 1932-3107
• DOI: 10.1177/193229681100500313

Based on our in vitro study that demonstrated the adverse effects of blood clots on glucose sensor function, we hypothesized that in vivo local tissue hemorrhages, induced as a consequence of sensor implantation or sensor movement post-implantation, are responsible for unreliable readings or an unexplained loss of functionality shortly after implantation. To investigate this issue, we utilized real-time continuous monitoring of blood glucose levels in a mouse model. Direct injection of blood at the tissue site of sensor implantation was utilized to mimic sensor-induced local tissue hemorrhages. It was found that blood injections, proximal to the sensor, consistently caused lowered sensor glucose readings, designated temporary signal reduction, in vivo in our mouse model, while injections of plasma or saline did not have this effect. These results support our hypothesis that tissue hemorrhage and resulting blood clots near the sensor can result in lowered local blood glucose concentrations due to metabolism of glucose by the clot. The lowered local blood glucose concentration led to low glucose readings from the still functioning sensor that did not reflect the systemic glucose level.