Details

Autor(en) / Beteiligte

• Dziong, D.
• Bagnaninchi, P.
• Kearney, R.E.
• Tabrizian, M.

Titel

A Highly Responsive System for On-line in vitro Assessment of Tissue Growth within MicroPorous Polymer Scaffolds

Ist Teil von

• 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference, 2005, p.1043-1046

Ort / Verlag

IEEE

Erscheinungsjahr

2005

Quelle

IEEE Xplore

Beschreibungen/Notizen

• We have proposed a highly responsive system for the on-line in vitro assessment of tissue growth within microporous polymer scaffolds that obviates any compromise of sample integrity. The system's function is based on the sample's loss factor: the imaginary part of the complex permittivity. Reflection measurements were performed using an open-ended coaxial probe and impedance analyzer; they were then related to the sample's complex permittivity by a quasi-static model of the probe's aperture admittance. Measurements of saline solutions showed that the real part of permittivity was corrupted by apparent polarization effects. Consequently, we developed a simplified formulation of the imaginary part of the Hanai-Wagner effective medium approximation to eliminate its dependence on the real part of complex permittivity measurement. This formulation allows the sample's cell concentration to be determined. The variation of a sample's cell concentration over time was used as a measure of tissue growth. Measurements in the frequency range of 10 - 200 MHz were performed on micro-porous polymer scaffolds seeded with progressively greater number of cells. Results demonstrated that the system detected concentration differences between cell-seeded scaffolds