Medical Device Research
Overview
I was an undergraduate researcher with the MIT Traverso Lab (June 2022 to February 2023), focusing on biomedical devices for controlled drug delivery. My research supervisor nominated me for the Ernesto Blanco Award for Outstanding Undergraduate Student in Mechanical Engineering, which I was awarded by the department in 2023.
Contributions
I worked on several projects with my supervisor, Dr. Seungho Lee. My contributions included:
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Conducting literature review and preparing summary presentations for dozens of scientific papers
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Performing Instron verification testing for gastric resident system
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Post-processing 3d-printed parts from resin printers
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Testing and optimizing isomalt pin casting process
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Assembling devices for pulsatile drug delivery
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Optimizing LPKF laser cutting parameters for implantable device
Skills
research | verification testing | 3d print post-processing | isomalt casting | LPKF laser cutting
Motivation
Lack of medication adherence is a global problem. Current methods of drug delivery often require frequent administrations, leading to lower patient compliance due to the inconvenience and discomfort of repeated injections or other administration methods.
In response to this issue, the Langer and Traverso Labs have been developing novel biomedical devices to increase adherence to long-term therapy. These devices require only a single implantation or administration and can allow controlled drug release without the assistance of a health professional or the patient’s awareness.
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By simplifying the drug delivery to a one-time administration system, this project aims to make disease treatment more accessible, increasing patient compliance in receiving their needed medication.
Gastric Resident System (GRS)
The gastric resident system is designed for gram-level dosage drug delivery, particularly for tuberculosis treatment. It consists of ingestible capsules which can be administered at a single hospital visit and reside in the stomach for extended drug delivery.
I conducted testing using an Instron machine to verify that the system could withstand the forces in the stomach (known from scientific literature) without passing through the pylorus further into the digestive tract.​​
Instron testing setup for three different numbers of capsules. The Instron cyclically simulates forces experienced in the stomach to test whether the device passes through the funnel, which is approximately the size of the pylorus. The left image shows a failure case, where the device passes through. The center and right images show successful trials, where the device does not pass through after repeated iterations.
Pulsatile Drug Delivery (PDD) Device
The pulsatile drug delivery system is an ingestible device that uses a loaded spring and microchannel-controlled pin release mechanism to control the timed release of a drug.
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The device relies on a small, dissolvable pin made of isomalt. These pins are cast from silicone molds. The casting process is very sensitive, as the pins are easily prone to breakage. As part of my research, I tested and optimized this process to maximize the production of intact pins.
isomalt pin to retain spring (spring not pictured)
microchannel with liquid to dissolve pin
Optimizing the pin casting process involved several iterative changes:​​
With these changes, in addition to careful precision and practice handling the delicate pins, I improved the process from a 0-20% success rate in producing usable pins to around 90% or above. I also modified the standard operating procedure (SOP) document and trained new students in this process.
Implantable Device
The implantable device was an earlier-stage project for applications in stem cell therapy. For this project, I worked on post-processing the 3d-printed (SLA) prototypes, using an ultrasonic cleaner and nitinol wire to remove support material from small cavities in the device.​​
I also experimented with an LPKF laser cutter to determine the smallest diameter holes that could be cut in a catheter insert. I iteratively tested different settings on the laser, analyzed the holes using a microscope imaging software, and recorded the parameters and results in a spreadsheet, which I used to determine the optimal settings and predicted hole diameter.
Reflections
Unfortunately I don't have much documentation for this project, as it was my first technical experience and I didn't take many pictures. While I decided not to continue my research due to schedule constraints, it was a good introductory learning experience.
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Since I spent my first summer working remotely, I did a lot of literature review before I started working in the lab. This was helpful to see the value of learning from existing research and figuring out which parts of papers are important and useful.
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Another major takeaway was the importance of testing and analysis. Especially in the medical device field, this is a crucial step of research and development, and there must be rigorous scientific reasoning for design choices and evidence that the device functions as it should.
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I also learned the value of asking good questions. My supervisor always encouraged me to ask questions not only for my own learning but also for the potential of considering things in a new light and improving the project. This was especially relevant as I was preparing to start my own project, but even though I decided not to continue research for now, I hope to apply what I learned in future experiences as well.