Oxygen Sensing Scaffolds for Determining Local Oxygen Tensions of the Cellular Environment

R. Patel, C. Broda, C. Ward, B.S. Harrison
Wake Forest University School of Medicine, US

Keywords: oxygen, tissue engineering, scaffolds

Summary:

Tissue engineering has made significant strides to develop transplantable tissue for patients needing organ replacements. However, to improve this approach, there is a need to probe the complex environment as tissue regeneration takes place since it plays a critical role in new tissue formation. Thus, developing a material capable of non-invasively probing the cellular environment would provide vital information on the regenerative process. This project set out to create a scaffold capable of detecting local oxygen tensions in the micro-environment. Electrospinning biodegradable polymers have been shown to produce nanofiber matrices similar to ECM. We enhanced the scaffolds with oxygen sensing abilities by electrospinning tris-4,7-diphenyl-1,10-phenanthroline ruthenium chloride in polycaprolactone. SEM and tensile tests revealed that the matrices were composed of randomly oriented nanofibers. The dye had no effect in morphology or mechanical properties. A MTS assay showed good cytocompatibility. The fluorescence change of the scaffold exposed to air-saturated and degassed water measured oxygen response. The results suggest that oxygen sensing dyes can be readily electrospun with minimal impact on the scaffold. The findings also demonstrated the ability to support cellular activity and detect differences in oxygen concentration. Such scaffolds may provide greater insight into designing tissue engineered scaffolds.