title: Sensing glucose concentrations at GHz frequencies with a fully embedded Biomicro-electromechanical system (BioMEMS).
abstract: The progressive scaling in semiconductor technology allows for advanced miniaturization of intelligent systems like implantable biosensors for low-molecular weight analytes. A most relevant application would be the monitoring of glucose in diabetic patients, since no commercial solution is available yet for the continuous and drift-free monitoring of blood sugar levels. We report on a biosensor chip that operates via the binding competition of glucose and dextran to concanavalin A. The sensor is prepared as a fully embedded micro-electromechanical system and operates at GHz frequencies. Glucose concentrations derive from the assay viscosity as determined by the deflection of a 50 nm TiN actuator beam excited by quasi-electrostatic attraction. The GHz detection scheme does not rely on the resonant oscillation of the actuator and safely operates in fluidic environments. This property favorably combines with additional characteristics-(i) measurement times of less than a second, (ii) usage of biocompatible TiN for bio-milieu exposed parts, and (iii) small volume of less than 1 mm3-to qualify the sensor chip as key component in a continuous glucose monitor for the interstitial tissue.
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: M
authors.initials: M
authors.lastname: Birkholz
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: K-E
authors.initials: KE
authors.lastname: Ehwald
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: T
authors.initials: T
authors.lastname: Basmer
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: P
authors.initials: P
authors.lastname: Kulse
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: C
authors.initials: C
authors.lastname: Reich
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: J
authors.initials: J
authors.lastname: Drews
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: D
authors.initials: D
authors.lastname: Genschow
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: U
authors.initials: U
authors.lastname: Haak
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: S
authors.initials: S
authors.lastname: Marschmeyer
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: E
authors.initials: E
authors.lastname: Matthus
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: K
authors.initials: K
authors.lastname: Schulz
authors.affiliation: IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany.
authors.forename: D
authors.initials: D
authors.lastname: Wolansky
authors.affiliation: Silicon Radar, Im Technologiepark 1, 15236 Frankfurt (Oder), Germany.
authors.forename: W
authors.initials: W
authors.lastname: Winkler
authors.affiliation: Humboldt Universität zu Berlin, Institut für Biologie, Invalidenstr. 42, 10115 Berlin, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Guschauski
authors.affiliation: Humboldt Universität zu Berlin, Institut für Biologie, Invalidenstr. 42, 10115 Berlin, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Ehwald