title: A MEMS Dielectric Affinity Glucose Biosensor.
abstract: Continuous glucose monitoring (CGM) sensors based on affinity detection are desirable for long-term and stable glucose management. However, most affinity sensors contain mechanical moving structures and complex design in sensor actuation and signal readout, limiting their reliability in subcutaneously implantable glucose detection. We have previously demonstrated a proof-of-concept dielectric glucose sensor that measured pre-mixed glucose-sensitive polymer solutions at various glucose concentrations. This sensor features simplicity in sensor design, and possesses high specificity and accuracy in glucose detection. However, lack of glucose diffusion passage, this device is unable to fulfill real-time in-vivo monitoring. As a major improvement to this device, we present in this paper a fully implantable MEMS dielectric affinity glucose biosensor that contains a perforated electrode embedded in a suspended diaphragm. This capacitive-based sensor contains no moving parts, and enables glucose diffusion and real-time monitoring. The experimental results indicate that this sensor can detect glucose solutions at physiological concentrations and possesses good reversibility and reliability. This sensor has a time constant to glucose concentration change at approximately 3 min, which is comparable to commercial systems. The sensor has potential applications in fully implantable CGM that require excellent long-term stability and reliability.
authors: Department of Mechanical Engineering, Columbia University, New York, NY 10027 USA.
authors: Xian
authors: X
authors: Huang
authors: Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 USA.
authors: Siqi
authors: S
authors: Li
authors: Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 USA.
authors: Erin
authors: E
authors: Davis
authors: College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
authors: Dachao
authors: D
authors: Li
authors: Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 USA.
authors: Qian
authors: Q
authors: Wang
authors: Department of Mechanical Engineering, Columbia University, New York, NY 10027 USA.
authors: Qiao
authors: Q
authors: Lin
keywords: Dielectric biosensor; affinity detection; continuous glucose monitoring; microelectromechanical systems technology