DLC Based BioMEMS Probe for Electrical Activity Recording of Tissues and Cells

C. Moldovan(a), R. Iosub(a), C.P. Lungu(b), A.M. Lungu(b), B. Firtat(a), C. Roman(a), R. Albulescu(c
a: National Institute for Research and Development in Microtechnologies, IMT-Bucharest, 126A Erou Iancu Nicolae Street, 077190 Bucharest, Romania
b: National Institute for Laser, Plasma and Radiation Physics, POBox MG-36, Magurele, Bucharest, Romania
c: National Institute for Chemical-Pharmaceutical R&D, 112 Calea Vitan, Bucharest, Romania

Abstract

An implantable probe for electrical activity monitoring of living tissues was engineered and fabricated on a silicon chip at IMT-Bucharest, Romania. In order to improve the mechanical resistance and biocompatibility of the device, the technology of Thermionic Vacuum Arc (TVA) deposition was used for coating the implantable parts with diamond like carbon (DLC) with zero stress (0SC). The paper presents the design and manufacturing steps of an DLC based 8-channel microprobe for recording the electrical activity of neural cells and tissues. The specific fabrication processes of the integrated microprobe are presented. The microprobe was packaged using gold wire bonding, in order to allow the electrical signals reading and processing. The electronics implemented on the board accomplish the separation and reduction of the biological noise recording. The microprobe functionality was tested in vivo and in vitro, in specialized laboratories, by recording electrical signals from cells cultures and mice organs. Biocompatibility tests were performed on implantable microprobes, coated with DLC/0SC, introduced in cells cultures. The integrated microprobe for monitoring tissues electrical activity can be used in laboratories and research centres acting in the biomedical field, which study the cells growth and their response to physico-chemical stimuli, in hospitals and treatment centres for people suffering from neurological diseases.