Design and Development of In Vivo Sensor Systems: The Long and Tortured Road to a Self-Contained, Implantable Glucose Sensor for Diabetes Management - Designing Receptors for the Next Generation of Biosensors - page 212

BIOSTABLE
INTERFACE

CLOSED-CYCLE
SENSING

SIGNAL
PROCESSING

RFID ENABLED
COMMUNICATION

Fig. 1 Critical components schematic. The key components of our approach are the bioselective
interface between the in vivo environment and the sensing system, the closed-cycle glucose
sensing system and a mass-sensitive signal transduction interface that is coupled to the RFID-
enabled data communication component

Fig. 2 Integrated sensor device design. The prototype glucose sensor will integrate the glucose
sensing system with a mass-sensitive signal transduction mechanism coupled to the RFID-enabled
communication electronics, all enclosed in a millimeter scale, implantable package

encapsulation and (2) facilitate the size-selective transport of the low molecular
weight fraction of the in vivo fluid matrix in and out of the device, while also
containing the mobile sensing system reagents (Fig. 3 ; see www.receptorsllc.com
for an animation of the implantable device). While each of these component pieces
is integral to the success of the device, the sensing system is the mission-critical
component.

2 Artificial Receptor Technology and the Development
of a Sensing System for an Implantable Glucose Sensor

Increasing demand for the detection of bioanalytes has triggered the development
of rapid assay techniques in the form of sensor technologies [ 17 , 43 - 45 ]. The
need for more robust sensors that transcend the cost and stability limitations of
current detection systems that require consumable biochemical reagents, such as
enzymes and antibodies, has fueled the trend toward the design and development of
sensing systems that are based on synthetic components like aptamers [ 46 - 48 ],
MIPs [ 49 - 51 ] and receptor constructs [ 52 , 53 ]. In addition, detection of bioanalytes