3D printing direct to industrial roll-to-roll casting for fast prototyping of scalable microfluidic systems.

Microfluidic technologies have enormous potential to offer breakthrough solutions across a wide range of applications. However, the rate of scale-up and commercialization of these technologies has lagged significantly behind promising breakthrough developments in the lab, due at least in part to the problems presented by transitioning from benchtop fabrication methods to mass-manufacturing. In this work, we develop and validate a method to create functional microfluidic prototype devices using 3D printed masters in an industrial-scale roll-to-roll continuous casting process. There were no significant difference in mixing performance between the roll-to-roll cast devices and the PDMS controls in fluidic mixing tests. Furthermore, the casting process provided information on the suitability of the prototype microfluidic patterns for scale-up. This work represents an important step in the realization of high-volume prototyping and manufacturing of microfluidic patterns for use across a broad range of applications.

Vascularized Polymers Spatially Control Bacterial Cells on Surfaces.

Nature uses vascular systems to permit large-area control over the functionality of surfaces that lie above them. In this work, the application of this concept to the control of a hybrid living-nonliving system is demonstrated. Defined arrangements of vascular channels are created in agar using a fugitive ink printing method. The antibiotic gentamicin is then introduced into the vascular network where it diffuses to the surface and interacts with a model system of Escherichia coli cells. The cells either live or die depending on their distance from the underlying channels, permitting spatial control over the biological system. Using single-channel systems to define critical parameters, a theoretical model is developed to define the final surface pattern based solely on the arrangement of the underlying vascular channels. The model is then successfully used to create more complex arrangements of cells at the surface. Finally, by introducing different types of active compounds into separate vascular channels, a mixture of bacterial species is separated and localized at defined points. This work demonstrates the ability of bioinspired embedded vascular systems to predictably control a biological system at a surface, laying the groundwork for future spatially and temporally controlled biointerfaces in both industry and medicine.