Strategies for testing long-term transcutaneous amperometric glucose sensors.

OBJECTIVES

Transcutaneous and embedded devices were developed for use in characterizing the in vivo performance of subcutaneously implanted glucose sensors. The devices were used as a portal for accessing electrochemical glucose sensors from the exterior. They were designed to prevent the sensors from being pulled out of the animals and the sensor leads from breaking. Development of the devices took into consideration rodent mobility, infection control, and animal welfare balanced with sensor durability, accessibility, and functionality.

METHODS

Our approach was developed over five animal protocols spanning a period of 6 months. A total of 68 sensors were implanted with 60 associated devices in 22 Sprague-Dawley outbred rats.

RESULTS

The average sensor lifetime was 11.2 +/- 3.1 days with a maximum of 56 days. All-cause sensor failure averaged one sensor per day. As implantation devices were modified, failure attributable to the device was decreased by 40%. The resulting devices showed good durability and allowed for easy sensor access and testing.

CONCLUSIONS

These data represent baseline sensor function against which future sensor improvements may be measured. The new devices and techniques described should be a valuable tool in the development of continuous glucose sensors.