3D Printed Multimaterial Microfluidic Valve.

We present a novel 3D printed multimaterial microfluidic proportional valve. The microfluidic valve is a fundamental primitive that enables the development of programmable, automated devices for controlling fluids in a precise manner. We discuss valve characterization results, as well as exploratory design variations in channel width, membrane thickness, and membrane stiffness. Compared to previous single material 3D printed valves that are stiff, these printed valves constrain fluidic deformation spatially, through combinations of stiff and flexible materials, to enable intricate geometries in an actuated, functionally graded device. Research presented marks a shift towards 3D printing multi-property programmable fluidic devices in a single step, in which integrated multimaterial valves can be used to control complex fluidic reactions for a variety of applications, including DNA assembly and analysis, continuous sampling and sensing, and soft robotics.

DNA Assembly in 3D Printed Fluidics.

The process of connecting genetic parts-DNA assembly-is a foundational technology for synthetic biology. Microfluidics present an attractive solution for minimizing use of costly reagents, enabling multiplexed reactions, and automating protocols by integrating multiple protocol steps. However, microfluidics fabrication and operation can be expensive and requires expertise, limiting access to the technology. With advances in commodity digital fabrication tools, it is now possible to directly print fluidic devices and supporting hardware. 3D printed micro- and millifluidic devices are inexpensive, easy to make and quick to produce. We demonstrate Golden Gate DNA assembly in 3D-printed fluidics with reaction volumes as small as 490 nL, channel widths as fine as 220 microns, and per unit part costs ranging from $0.61 to $5.71. A 3D-printed syringe pump with an accompanying programmable software interface was designed and fabricated to operate the devices. Quick turnaround and inexpensive materials allowed for rapid exploration of device parameters, demonstrating a manufacturing paradigm for designing and fabricating hardware for synthetic biology.

Better together: engineering and application of microbial symbioses.

Symbioses provide a way to surpass the limitations of individual microbes. Natural communities exemplify this in symbioses like lichens and biofilms that are robust to perturbations, an essential feature in fluctuating environments. Metabolic capabilities also expand in consortia enabling the division of labor across organisms as seen in photosynthetic and methanogenic communities. In engineered consortia, the external environment provides levers of control for microbes repurposed from nature or engineered to interact through synthetic biology. Consortia have successfully been applied to real-world problems including remediation and energy, however there are still fundamental questions to be answered. It is clear that continued study is necessary for the understanding and engineering of microbial systems that are more than the sum of their parts.