Oxygen-Sensing Microfluidic Scaffolds

Oxygen in living tissues is a key soluble factor in normal as well as pathological processes. In relation to cancer, the development of oxygen-depleted tumor niches is thought to play an important role in tumor growth and metastasis. An outstanding challenge remains to develop an in vitro system where one can control and monitor oxygen concentration in a spatiotemporal manner within a three-dimensional (3-D) cell-seeded tissue scaffold. We propose the development of oxygen-sensing microfluidic scaffolds, which meet this challenge. Our strategies include 1) the synthesis of oxygen-sensing microbeads, 2) characterization of the beads via both direct imaging of phosphorescence and measurement of phosphorescence lifetime, and 3) visualization and measurement of oxygen-depletion lengths in a simple microfluidic tumor model.