Real-Time Impedance Monitoring of Epithelial Cultures with Inkjet-Printed Interdigitated-Electrode Sensors

Area of Science:

• Biomedical Engineering
• Materials Science
• Electrical Engineering

Background:

• Printing techniques offer versatile applications from electronics to tissue engineering.
• A hybrid platform for simultaneous fabrication of sensors and engineered tissues is envisioned.
• Monitoring cell behavior in vitro is crucial for tissue engineering and disease modeling.

Purpose of the Study:

• To fabricate and characterize inkjet-printed interdigitated-electrode sensors (IDEs) for monitoring epithelial cell cultures.
• To demonstrate the potential of these sensors for real-time, label-free monitoring of skin tissue models.
• To explore the feasibility of integrating these sensors into a hybrid 3D-bioprinted smart skin substitute technology.

Main Methods:

• Fabrication of IDEs on flexible substrates using silver nanoparticles and SU-8 passivation via inkjet printing.
• Development of a real-time impedance spectroscopy system for label-free monitoring.
• Culturing and monitoring of keratinocytes to assess proliferation, migration, and detachment.

Main Results:

• Inkjet-printed IDEs are cytocompatible and feature a microgrooved topography.
• Sensor performance remains stable after reuse for cellular studies.
• Impedance variations correlate linearly with initial cell seeding densities.
• Cell membranes are the primary determinant of total impedance.
• Impedance measurements accurately track keratinocyte migration, correlating linearly with image processing methods.

Conclusions:

• Inkjet-printed sensors offer a low-cost, non-destructive method for in-situ monitoring of in vitro epidermal models and wound healing.
• The developed flexible sensors and impedance spectroscopy technique are promising for hybrid 3D-bioprinted smart skin substitutes.
• This technology facilitates the integration of electronics with engineered tissues for advanced biomedical applications.