Event
PhD Research Proposal Exam: Michael Straker
Tuesday, October 10, 2023
10:00 a.m.
5104 A James Clark Hall
Michael Straker
mstraker@umd.edu
The prevalence of gastrointestinal (GI) disorders has driven a need for medical screening for chronic conditions such as Celiac Disease (CD), inflammatory bowel disease (IBD), and GI cancers.
The standard screening method for GI health conditions is endoscopic biopsy in which a medical professional visually surveys the bowel for suspected pathological tissue and resects a sample for further analysis. This method is not only costly due to the need for operation by a medical professional but also carries risks associated with the sedation methods that accompany the procedure. Additionally, endoscope have a limited range of operation within the GI tract making remote areas such as the small intestine inaccessible.
Ingestible capsule devices have emerged as a promising technology for overcoming the limitations of endoscopic biopsy, however, the current capsule designs suffer from key shortcomings that impede practical application. The devices designed for tissue resection utilize power consuming actuation mechanisms, require active operation by a medical professional, or cannot collect tissue samples of suitable quality for useful characterization.
My proposal is to develop an ingestible capsule feedback-triggered actuation module that can resect, protect, and preserve tissue in remote regions of the GI tract. Preliminary results demonstrate the ability to protect and selectively release an actuator intended to interact with GI tissue.
An actuation module will be designed and optimized utilizing a slotted cam and follower mechanism in Aim 1. The module will be fabricated via 3D Printing and evaluated for its force output. The collection mechanism of the module will be further developed to ensure the preservation of the sample quality and mitigate tissue perforation in Aim 2. The resection mechanism will adapt the methodology of skin tissue biopsy for collection of GI tissue via a 3D-printed barbed biopsy punch. Preservation of the tissue via non-toxic fixatives and sealing of the module cavity will also be explored to mitigate post-resection sample degradation or contamination. The module will be components be combined and integrated into an ingestible capsule platform in Aim 3.
To demonstrate the module’s ability for feedback driven activation, the capsule will incorporate a sensor for location indication based on pH. The device will be evaluated for its ability to resect a sufficient volume of ex vivo intestinal tissue on a custom fabricated GI simulation apparatus.
Preliminary work has demonstrated the use of the apparatus in evaluating a pH-responsive bilayer coating for protecting and selectively exposing ingestible capsule components. This coating will be used to fabricate the location indicating sensor. Successful completion of the proposed research will result in the development of a means of performing biopsy of mucosal tissue from previously inaccessible regions of the GI tract. Such a technology will give way to a new generation of autonomously acting ingestible devices for GI health monitoring and research.
