Uniform perfusion of fluid through microbores in a hydrogel scaffold using a microfluidic manifold device

Hydrogel scaffolds, both synthetic and biological, are an important component for microscale and macroscale tissue fabrication. Owing to their high water content, hydrogel scaffolds enable the distribution of nutrients and oxygen to support cells in larger constructs. However, thickness of hydrogel scaffolds is still limited by the diffusion rate of nutrients and oxygen, versus the metabolic rate of the cell culture. The creation of microbore conduits within a hydrogel scaffold can overcome these limitations. Here, controlled perfusion through a hydrogel scaffold is demonstrated with a microfluidic manifold device. The flow profile was simulated to aid in the device design, and flow control was validated experimentally. We used this system to determine the diffusion coefficient of two model solutes, one with a small molecular weight and one with a large molecular weight, through the hydrogel scaffold.