Team:Penn/Description
MIYAGI
Wax printing can be used to fabricate microfluidic paper-based analytical devices (µPADs), which have emerged as promising platforms for developing low-cost diagnostic devices in resource-limited settings.
Learn more about applications and current methods of wax printing here.However, current methods of wax printing are expensive and difficult to source, limiting the scope of fabrication of wax-printed µPADs. The most common wax printer is the Xerox ColorQube printer. While the Xerox printer can be used to fabricate µPADs, this process requires a post hoc heating process to fully allow the wax to permeate through the paper. The heating not only adds another step to the process but also decreases the device resolution due to the heated wax spreading laterally into the paper channels. The Xerox printer is also no longer manufactured and can only be purchased second hand for ~$1500 and requires expensive wax cartridges.
Table 1 : Comparison of our MIYAGI wax printing conversion kit and the current wax printing standard, the Xerox ColorQube printer. Our MIYAGI kit is only an additional ~$300 to the cost of a Prusa ($750). Our device is an open source and easy to use method of wax printing that can be readily implemented by educational and research labs.
This is what inspired Penn’s iGEM team: To increase accessibility of wax printing for all.
Our Proposal
We intend to design and build an open source wax printing conversion kit for the Prusa i3 MK3S. Our conversion kit will incorporate a custom metal syringe holder that allows uniform heating of wax, and a pressure-driven extrusion system that allows permeation of wax through paper, streamlining the printing process. With minor modifications, this project will allow people all over the world to convert any 3D printer into a wax printer for the fabrication of µPADs.
Custom Metal Syringe Holder
Adapted Open Source 3D Printer
Pressure Driven Extrusion
How to Use it
SOFTWARE: To use MIYAGI, a STL file of the desired microfluidic device is uploaded into a 3D-Slicer to convert it into G-code. This G-code is then put into our custom munging script to modify it for wax extrusion. The modified G-code can then be uploaded to the printer and run. HEATING: Simultaneously, paraffin wax is put into a syringe that is then loaded into the syringe heater on MIYAGI. PRESSURE: To control extrusion MIYAGI uses a pressure system controlled by the G-code. Pressurized nitrogen, or alternatively pressurized air, is run through a regulator that controls the exact air pressure. It then goes to a 3 way 2 position solenoid whose position is controlled by the switching on and off of the fan port by G-code. The solenoid is connected to the syringe via a 3D printed syringe adaptor that uses the syringe plunger to create an airtight seal.
MIYAGI & Society
Paper-based µPADs are very attractive as point-of-care analysis devices due to their inexpensive and disposable materials and their ability to perform assays without external pumps. They can be used as rapidly-prototyped diagnostic tests in resource-limited settings, ideal for this application because of the ease of use and portability of such devices. Since 2007, when µPADs were first developed, they have been implemented throughout the world in detecting infections and diseases such as Ebola, Salmonella, and Hepatitis C . Because of the need for rapid diagnosis of many of these diseases, µPADs allow for quick detection in areas lacking easy access to laboratories or health care centers. MIYAGI focuses on making these devices easier to fabricate and more accessible by converting an existing 3D filament printer to a wax printer. This device will replace the need for large and expensive equipment and the complicated protocols of many current microfluidic device fabrication methods. It will make the fabrication process quicker, easier, and cheaper, and will allow more people around the world to create uPAD diagnostic tests. In turn, more people in healthcare-limited settings will be able to be diagnosed and consequently treated for illnesses that otherwise would have remained undetected.
One example of extensive uPAD research is Wyss institute’s low-cost, paper-based diagnostic system that was developed for detecting different strains of Zika virus. The goal was to make a point of care device that would analyze blood, urine, or saliva samples in the field. Photo Credit: Wyss Institute at Harvard University.
Read more here
MIYAGI & Synthetic Biology
Microfluidic devices have become increasingly common in synthetic biology applications. These devices allow for precise control of the environmental conditions of assays and for acquisition of single gene expression data. They also require lower costs than traditional large-scale experiments and produce high throughput and reproducibility while requiring very little reagent volume. MIYAGI will make these promising experiments more attainable by offering an easy and low-cost method for fabricating microfluidic devices.
Wyss Institute integrates principles of synthetic biology into a paper-based diagnostic system for a proof of concept test with the Ebola virus. Photo Credit: Wyss Institute at Harvard University
Read more here