Overview >>                      Glucose sensor development

 

Motivation The detection and quantitative determination of biomolecules is a central task in modern biotechnology and medicine, for which smart solutions may be supplied by microelectronic technology [1]. In particular, the continuous monitoring of blood sugar (glucose) in diabetics is a pressing issue, since the diabetes mellitus disease has taken pandemic-like dimensions and poses severe economic constraints to the public health system. The high costs are mainly due to diabetes-related complications, which are often caused by an inadequate blood sugar adjustment. In consequence, persistent hyperglycaemic conditions often occur that can cause vascular damage and may lead to cardiac infarctions and apoplectic strokes. It would thus be highly desirable to dispose of a bloodless method for continuous glucose monitoring that is compatible to the discontinuously operating methods widely used today.

The Objective A sensor chip has been developed at IHP that determines glucose levels by the principle of affinity viscosimetry [2]. The chip is fabricated as a fully integrated microelectromechanical system (MEMS), in which the viscosity of a liquid can be determined from the bending of an elastic cantilever [3, 4]. Thanks to modern micro technologies [5, 6] the sensor exhibits small dimensions of only 1.3 x 0.4 x 0.2 mm and is well suited for semi-invasive devices for continuous glucose monitoring in diabetics patients. Within the GlucoPlant project we currently investigate the question, whether the sensor chip may also apply for an implantable glucose monitor [7]. The answer to this question will be decided about by the degree of miniaturization of which the full system is capable and by the biostability of the sensor chip.

Funding The GlucoPlant project is funded within the „Intelligente Implantate“ program of the Bundesministerium für Forschung und Wissenschaft (BMBF) via Projektträger vdi/vde/it Berlin.

Members of GlucoPlant Application Board
 AG Zellbiologie Humboldt-Universität zu Berlin, Bio Sensor Technologie GmbH, Charité Berlin, Schlosspark-Klinik Berlin, Sitec-Sensortechnik GmbH, and others

Publications [1] M. Birkholz, Konvergenz in Sicht – zur gemeinsamen Perspektive von Mikroelektronik und Biotechnologie, in: LIFIS ONLINE, 29.7.2009

[2] M. Birkholz, K.-E. Ehwald, R. Ehwald, M. Kaynak, J. Borngräber, J. Drews, U. Haak, J. Klatt, G. Schoof, K. Schulz, B. Tillack, W. Winkler, D. Wolansky, Mikroviskosimeter zur kontinuierlichen Glucosemessung bei Diabetes mellitus, in: H. Seidel, H. Reichl and W. Lang (Eds.): Proceedings Mikrosystemtechnik Kongress 2009, Berlin, VDE-Verlag, Berlin, 2009, p. 124.

[3] M. Birkholz, K.-E. Ehwald, D. Wolansky, I. Costina, C. Baristiran-Kaynak, M. Fröhlich, H. Beyer, A. Kapp, F. Lisdat, Corrosion-resistant metal layers from a CMOS process for bioelectronic applications, Surface and Coatings Technology 204 (2010) 2055.

[4] M. Birkholz, P. Kulse, K.-E. Ehwald, M. Kaynak, J. Drews, M. Fröhlich, U. Haak, K. Schulz, D. Wolansky, Ultrathin TiN-Membranes as a Technology Platform for CMOS-integrated MEMS and BioMEMS applications, Advanced Functional Materials 21 (2011) 1652-1656.

[5] M. Birkholz, K.-E. Ehwald, M. Kaynak, T. Semperowitsch, B. Holz, S. Nordhoff, Separation of extremely miniaturized medical sensors by IR laser dicing, J. Optoelectr. Adv. Mat. 12 (2010) 479.

[6] P. Kulse, M. Birkholz, J. Bauer, J. Drews, U. Haak, J. Katzer, S. Marschmeyer, D. Wolansky, K. Schulz, CMOS-embedded BioMEMS with backside-etched cavities for affinity sensorics, E-MRS Spring Meeting, Symposium O, Nice, May 2011.

[7] T. Basmer, P. Kulse, M. Birkholz, Systemarchitektur intelligenter Sensorimplante, Biomedical Engineering / Zeitschrift für Biomedizinische Technik 55 (2010) 43.