Team 8

Members: Hebah Alkhalifah, Justin Parks, Bam Saithale, and Anna Snider

Project Sponsor: Dr. Lester Smith, PhD, Assistant Professor of Radiology & Imaging Sciences, IU School of Medicine


Fluid Control System for Use in a Bioreactor

Background

Tissue Engineering Research

Tissue engineering is comprised of engineering cells, materials and architecture through the application of mathematics, physics, biology, and chemistry. Through application of these scientific principles with existing instrumentation and innovative research, progress in tissue engineering is made which works to further the knowledge and treatment of human health and diseases.

Innovation in Tissues is either to restore, maintain, or improve existing tissues.

  1. Restore: Tissues that have been lost to a disease state.

  2. Maintain: Tissues that are healthy are are grown for replacement use, such as skin grafts.

  3. Improve: Tissues that are below a standard level, and are improved to restore healthy state.

Implications of Tissue Engineering include cost and environmental and societal impact.

  1. Cost: Researchers must maximize cost efficiency with the products they produce, so that grant funding is budgeted appropriately leading to results of highest quality.

  2. Environmental Impact: Research in general, and specifically tissue engineering and medical research produce tons of waste from single-use plastics and biohazard waste as tissues are carefully tended to as to avoid contamination that would ruin or stunt development. The creation of engineering tools that are reusable will begin to lower the overall measure of yearly waste stemming from laboratory research.

  3. Societal Impact: Products that are made in laboratories are meant to further research. Furthering research across multiple scientific disciplines in medicine leads to the furtherment of the successful development of medical treatment and therapies to treat humans of all socioeconomic classes.

Sponsor Specific Use

The sponsor's area of research is culturing cells in a bioreactor and perfusing media in a closed loop system with a peristaltic pump. He currently utilizes a metal 3-way stopcock and needle-free valve system to aseptically process the removal and replacement of cell culture media with a syringe as can be seen in the image to the right. Current issues exist in the system which requires a replacement design to be constructed. The metal stopcock prevents closed system imaging of cells under magnetic resonance imaging (MRI), as the ferrous nature of the stopcock is incompatible with the magnetic field the imaging produces. The needle-free valve is single-use and thus contributes to laboratory waste. Neither the stopcock nor the needle-free valve are readily available, meaning both must be purchased from a reputable company, and their arrival is dependent upon the speed of the company processing and U.S. mail. For these three reasons, the three main differences between the existing solution and the designed solution will be that the stopcock and needle-free valve functionalities will be crafted from non-ferrous material, be reusable, and be crafted in-house by 3D printing and silicone molding.

ABOVE: Current sponsor fluid control system consisting of (from top to bottom) stopcock, needle-free valve, and syringe.

BELOW: The total bioreactor system with fluid control system in place.

Process Flow Diagram

Problem Statement

A way for tissue engineering researchers to have a rapidly prototyped, biocompatible, and autoclavable system to manually control the direction of fluid flow and replace fluid aseptically from tubing in a bioreactor. ​

Key User Needs


Biocompatibility

Biocompatibility is one of the most important features in the redesign of the fluid control system. Failure to achieve this user need results in damaged and unusable tissues. Biocompatibility will consist of a biological pH range as well as the non-dissolution of atoms or ions from the material of which the device is comprised.

Fitment

Fitment is essential to the use of the fluid control system. No leakage may occur so that a closed and aseptic processing will ensue. Fitment in multiple areas must be satisfied. Tubing must fit with an airtight seal around the stopcock, the needle-free valve functionality must have an airtight seal unless under the pressure of a syringe, and the entire device must fit through an opening in the back of an incubator for cell culturing.

Compatibility with MRI

The device must be made of non-ferrous material as to be compatible with MRI.

Readily Accessible

The device must be made in-house with the sponsor's existing materials. This will include BioMed Clear Resin, and Elastosil 601 silicone. With these materials the device can be first printed on an SLA printer and subsequent pieces molded from silicone.

Reusability

The device must be reusable as to reduce waste within the laboratory. This will include requirements of being easily cleaned, and autoclavable to the sponsor's settings, for at least 50 times.

Prototype Evolution

Prototype Demonstration


prototypedemo.mp4

The final design consists of the stopcock, silicone insert, stopcock base and pinch clips as seen in the prototype demonstration and in prototype evolution in the third design. The silicone insert is placed inside the stopcock and the base is rotated 90 degrees and locked into place. This combines both the stopcock and needle-free valve functionality. The pinch clips are to satisfy the obstruction of flow needed in a stopcock fluid control system. The bulb is used to place the clip around the tubing, and sliding the pinch clip downward so that flow is prevented by the thin slit in the pinch clip.

The newly designed stopcock with syringe attached and pinch clips obstructing flow.

Poster


The Team

Acknowledgments

Special thanks to Dr. Miller, Dr. Smith, Dr. Yoshida, Onna Dehring, Dr. Yoshida and Sherry Clemens for their help in instruction, sponsorship, equipment order and idea generation for this senior design project.