First clinical evaluation of a new long-term subconjunctival glucose sensor

• Published in: Journal of diabetes science and technology Vol. 6; no. 4; pp. 875 - 883
• Main Authors: Müller, Achim Josef, Knuth, Monika, Nikolaus, Katharina Sibylle, Herbrechtsmeier, Peter
• Format: Journal Article
• Language: English
• Published: United States Diabetes Technology Society 01.07.2012
• Subjects: Adult; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Blood Glucose - analysis; Blood Glucose Self-Monitoring - instrumentation; Blood Glucose Self-Monitoring - methods; Circadian Rhythm - physiology; Concanavalin A - analysis; Conjunctiva; Diabetes Mellitus - blood; Diabetes Mellitus - therapy; Feasibility Studies; Female; Fluorescence Resonance Energy Transfer - instrumentation; Humans; Implants, Experimental; Male; Middle Aged; Models, Biological; Original; Pilot Projects
• ISSN: 1932-2968; 1932-3107
• DOI: 10.1177/193229681200600419

To evaluate the feasibility of an implantable subconjunctival glucose monitoring system (SGMS) for glucose monitoring in humans, we investigated the in vivo performance of the sensor in a clinical trial with five patients. The new SGMS consists of an implantable ocular mini implant (OMI) and a hand-held fluorescence photometer. The implantable subconjunctival glucose sensor is composed of a fluorescence resonance energy transfer system based on Concanavalin A chemistry, embedded in a nelfilcon polymer hydrogel disk. Blood glucose changes in humans were induced by oral glucose intake and insulin injections. The in vivo response of the new SGMS was tested in a first human clinical study with five diabetes patients. The OMI was well tolerated in the eyes of the patients. The SGMS exhibited high correlation coefficients (>0.88) with blood glucose changes and a good stability of the sensor response to glucose for the study period of 2 weeks. Lag times were in the range of 5-10 min. A total of 98% of all data pairs was in the clinical acceptable ranges A and B of the consensus error grid. For the first time, the possibility to measure glucose in vivo in the subconjunctival interstitial fluid for a period of 2 weeks was demonstrated in a human clinical trial.