Wireless monitoring of collagen progression around implantable prostheses

Bıocompatıbılıty remains a critical issue due to the foreign body response following device implantation. “Collagen” is the main bio-material composed around the implanted devices. This paper reports the possibility to measure the thickness of the “Collagen layers” using impedance measurement. An implanted passive circuit sensitive to the collagen thickness is wirelessly connected to the external reading circuit through inductive coupling. The resonance frequency of the system is directly proportional to the Collagen layer thickness variation. A modeling and simulation study of the Collagen material is presented by “COMSOL” to verify the functionality and obtain the optimal design parameters. Reported results demonstrate the increment of collagen capacitance from 30fF to 120fF when the collagen thickness rises from 1mm to 6mm. The experimental validation is reported using Impedance Analyzer. The measured resonance frequency drops from 55.78MHz to 54.98MHz when the collagen thickness increases from 0 to 10mm.