The control syringe system we implemented in TERRA was repurposed from the 2016 Boston University iGEM Hardware Team, Neptune. Neptune designed an end to end design suite for continuous flow microfluidics, which helped automate the microfluidic design process. The team coupled this design software with DIY syringe pumps hardware, which are responsible for inputting flow into the microfluidic chip, to increase the accessibility of microfluidics due to the high cost of retail syringe pumps.
Our team decided to repurpose Neptune’s syringe pump hardware to develop our control syringe system because they already went through the process of designing and validating a DIY platform for automating syringe movement. In addition, since the syringe pumps were used to gradually push a syringe to dispense at a constant rate, they were able to demonstrate a high degree of controllability with their hardware platform. This gave us the confidence to reuse their hardware platform for our control syringe system in TERRA.
However, because of the difference in application between Neptune and TERRA, we needed to update the software operating the syringes. TERRA’s control syringe system is responsible for actuating control valves on the TERRA Adapter as opposed to inputting constant flow. In addition, the control syringes needed to work alongside the other components of TERRA, particularly the XY Plane and UI. To accomplish this the control syringes system needed to be able to sustain on/off states based on the output selection system on the TERRA Adapter in order to dispense the proper product into the vessel. In order to execute this, we programmed the servo motors for the syringes to move and hold certain positions based on the experiment protocol given by the user. These positions would last for a certain duration, depending on how long an output is selected for. Then, based on the experiment protocol from the UI, these on/off states were coupled with specific outputs on the microfluidic chip to control which when they would be dispensed and how much. These improvements to the software enables us to reuse the hardware for a wider range of applications, and thus adding additional value to these DIY syringe pumps.
To learn more about how the control syringe system works visit:
Improving on MARS
The 2017 Boston University iGEM Hardware team, MARS, created a repository of chip designs called the MARS Repository. The MARS Repository contains design information and files of the nine different synthetic biology protocol chips MARS had designed. The data contained in the MARS Repository is open to the public and allows synthetic biologists to utilize microfluidics without designing a custom microfluidic chip.
A main goal of our project is to increase the accessibility of microfluidics, so we have decided to uploaded the documentation and design files of the microfluidic chips we have designed to the MARS repository. We have created the following chips and introduced them to the MARS Repository:
The TERRA Adapter is a scalable, predesigned chip that is capable of selectively dispensing the output of the microfluidic chip running the experiment into the intended lab vessel. The TERRA Adapter serves to increase the number of and types of microfluidic chips that are compatible with our system. This makes the system more user-friendly, as they don’t have to design a chip that both completes a biological experiment and is capable of selecting the proper output to be dispensed.
Click here to learn more about the design of the TERRA Adapter:
This chip was designed to encapsulate sodium alginate, calcium chloride, and cells suspended in media in droplets for later use in the Harvard iGEM team’s keratin skin patches. These chips consist of three aqueous inputs that combine without mixing into one input that is then pinched by the oil channels at the droplet generator to create droplets.
Click here to learn about the Harvard Collaboration:
Inspired by the InterLab Study, this series of chips attempt to follow the protocol of running three consecutive 1:20 dilutions followed by a pair of consecutive 1:10 dilutions. These sequences of mixers are then paired with an valve actuated output selection mechanism such that either the third, fourth, or fifth dilutions can be selectively dispensed onto an agar plate. Since the real estate on our desktop CNC milled microfluidic chips are limited, this protocol has divided into two chips which, when run in tandem, accomplish these specific serial dilutions. The first chip in the system consists of three consecutive mixers, design with flow rates intended to handle the three 1:20 dilutions. The other chip will run the two 1:10 dilutions and the output selection mechanism.
Click here to learn about the BostonU Collaboration:
This microfluidic chip consists of three parallel systems, each designed to mix the TX-TL cell free solution and specific substrates needed to yield the desired colorimetric product. These three systems are combined by a series of valves that serve as a selection mechanism that directs the desired colored solution to the chip’s output.
Click here to find the design documentation of the chip:
Click here to find the fabrication documentation and SVG files: