Project Title: A Surface Characterization Device for Engineering Labs and Senior Design Projects

Project Lead's Name: Dr. Amy Yousefi

Project Lead's Email: yousefiam@MiamiOH.edu

Project Lead's Phone: 513-529-0766

Project Lead's Division: CEC

Primary Department: CPB

Other Team Members:

• Jace Vu
• Jackson Conroy

List Departments Benefiting or Affected by this proposal:

• CPB
• MME

Estimated Number of Under-Graduate students affected per year (should be number who will actually use solution, not just who is it available to): 60

Estimated Number of Graduate students affected per year (should be number who will actually use solution, not just who is it available to): 10

Describe the problem you are attempting to solve and your approach for solving that problem:

Experiential learning is a key element of the Miami education and prepares our engineering students for careers in medical device companies, chemicals industries, and research labs, among others. The device requested in this proposal can be used for water contact angle measurements while enabling the characterization of the surface energy of materials. Surface properties greatly influence the host response to medical devices and can play a key role in cell adhesion to tissue-engineering scaffolds.

Most CPB faculty are involved in research on materials/biomaterials or teaching courses that will benefit from the device requested in this proposal. For example, students prepare soft-tissue mimicking hydrogels (cryogels) in the lab offered in CPB 419/519 and learn about additive manufacturing of tissue-engineering scaffolds. Some important topics that are covered in CPB 419/519 include surface characterization of biomaterials, surface energy, and surface contamination in air and water. Acquiring the proposed surface characterization device will enable CPB to offer two additional lab experiments in CPB 419/519. Hydrophilic polymers, such as poly(vinyl alcohol) (PVA), and hydrophobic polymers, such as poly(lactic-co-glycolic acid) (PLGA), will be exposed to water before and after surface modification using argon plasma. Measuring the water uptake, water contact angle, and surface energy will enable the students to analyze the effect of argon plasma treatment on the surface characteristics of biomaterials.

Furthermore, most CPB faculty have incorporated their research into the courses they teach. For example, demonstrations of additive manufacturing (e.g., 3D-bioplotting and 3D-printing) have been integrated into the labs offered to undergraduate and graduate students (CPB 419/519 and CPB 102). Biomedical Engineering and Chemical Engineering students take these courses, as well as the graduate students from CPB and Mechanical and Manufacturing Engineering (MME) who enroll in CPB 519. Other students who will benefit from the requested device include undergraduate seniors enrolled in engineering design courses (CPB 471/472), independent studies (CPB 277/377/477), undergraduate summer scholars (CPB 340U), as well as graduate students working on their MS thesis (CPB 700).

How would you describe the innovation and/or the significance of your project:

CPB 419/519: The biomaterials course ― taught by Amy Yousefi ― currently has no lab experiment to compare the surface energies of biomaterials, or to show the effect of surface modification on altering the hydrophobicity of biomaterials. This is a very important practical aspect, which directly affects the suitability of a material for biomedical applications. When exposed to surrounding air, hydrophobic elements tend to migrate to the surface of a biomaterial. In addition, contaminants in the air can readily cover the surface of certain biomaterials, depending on the magnitude of their surface energy (Fig. 1, Supporting Information). CPB recently acquired a plasma surface activation chamber, which was made possible by a Tech Fee grant. This equipment alone is not adequate to demonstrate the concept of surface energy modification in CPB 419/519. The surface characterization device requested in this proposal can greatly contribute to students’ learning outcomes. While the existing chamber offers an effective method for nanoscale surface cleaning and surface activation, which alters the surface energy, the surface characterization device will play a key role in characterizing the change in hydrophobicity and quantifying the surface energy.

CPB 471/472: The CPB department offers other experiential learning opportunities to undergraduate students via senior design projects (CPB 471/472). Placing the requested equipment in the lab space used by senior design students will maximize its utilization. Examples of senior design projects for 2021/2022 is the “inhibition of growth of yeast on polypropylene for application in hygiene products” mentored by a CPB faculty. Jace Vu, a co-applicant on this Tech Fee proposal, is a team member of this senior design project and intends to use the requested surface characterization device in his CPB 471/472 project. Jace is urged by the need to probe the surface interaction of his team’s ZnO deposition layer with water. In sanitary products, polypropylene linings would orientate the flow of bodily fluids on their surfaces. The team's configurations to enhance the anti-microbial properties of said polymer films would only be meaningful in the industrial production setting if body-material surface interactions retrieve favorable and reproducible results. The contact angle device would significantly aid the team in the design process. All of which research advancements could only happen if this Tech Fee proposal is granted funding.

CPB 277/377/477: Hands-on experience with additive manufacturing has become an integral part of many engineering programs in the nation. Surface characterization of biomaterials is a crucial step in evaluating the eventual interaction between biological tissues and medical devices (or tissue-engineering scaffolds) in clinical settings. Miami students have successfully used a 3D-bioplotter at CPB to prepare 3D scaffolds made of biological and synthetic materials, which can eventually serve as bone graft substitutes (Fig. 2, Supporting Information). Some additive manufacturing techniques tend to create smooth surfaces, which could be detrimental to cell adhesion. Jackson Conroy, a co-applicant on this Tech Fee proposal, is currently involved in an independent study that aims to prepare composites of biological/synthetic 3D scaffolds using 3D-bioplotting and solvent casting. In collaboration with Jace Vu, the team will investigate the role of argon plasma on the surface characteristics of 3D scaffolds made of collagen, PLGA, and nanohydroxyapatite (nHA). Surface characteristics play a vital role in the interaction of polymeric scaffolds and native cells in the body. If this Tech Fee proposal receives funding, the proposed equipment will enable the team to quantify the water contact angle and surface energy of these 3D scaffolds. Hydrophobicity of the material could thus be characterized by its surface interaction with water droplets. Since the constituted medium inside the body is aqueous, the device will procure useful and practical information for the objective of this research study. Furthermore, contact angle measurement is the preferred method of choice in this study due to its affordability and simplicity, and the device requires minimal training to be operated. It is believed that by successfully purchasing the device and obtaining readings of the scaffold surface characteristics, this project could benefit substantially in the fullness of time. Finally, the contact angle measurement device could also inspire future projects to examine and modify the surface chemistry of these 3D scaffolds.

CPB 700: Most CPB faculty and their graduate students conduct research on materials/biomaterials. In addition to CPB & MME graduate students enrolled in CPB 519, the proposed equipment will provide our graduate students with a tool to properly characterize their research samples. As pointed out earlier, placing the requested equipment in a shared educational lab space will maximize its utilization. As the current graduate program director, Dr. Amy Yousefi will bring this equipment to the attention of our graduate students and will invite the other CEC departments to use the device (via CEC Graduate Council). Every effort will be made to make sure that all the equipment purchased via Tech Fee funds attains its maximum utilization capacity.

How will you assess the success of the project?

Lab Experiment 1:

Figure 3 (Supporting Information) shows a PLGA scaffold that CPB students have designed in CPB research labs. These hierarchical PLGA/nHA scaffolds with micro-, macro-, and nano-scale features can contribute to cell attachment and growth via different mechanisms.

• The requested surface characterization device, combined with a plasma surface activation chamber, will be used in CPB 419/519 labs for surface modification of these scaffolds.
• Samples before and after surface modification will be used to measure the contact angle and quantify the surface energy. The water contact angle formed on the surface of the scaffold will be analyzed to compare the surface energy before and after surface activation.
• Once the team reports were submitted (part I), the collected data by all teams will be uploaded to Canvas to allow students to perform statistical analysis (mean, standard deviation, and t-test).

Lab Experiment 2:

Figure 4 (Supporting Information) shows the typical PVA hydrogels produced by the freeze-thaw technique (including in CPB 419/519 lab). The material used for producing these gels is an aqueous solution of PVA. Here are the steps that students will follow for this lab experiment:

• PVA (1 gr) and DI water (20 ml) will be mixed and heated at 85°C on a hot plate/stirrer.
• The prepared solution will be poured into aluminum molds (20-mm diameter).
• The set-up will be placed inside a freezer at ±20°C.
• The samples will be removed from the freezer after 24 hours.
• After removing from the freezer, one wet sample will be weighed (M1,t0) and immersed in DI water.
• After removing from the freezer, two wet samples will be placed inside the plasma surface activation chamber for two different periods, weighed (M1,t1 and M1,t2), and immersed in DI water.
• The water-swollen samples will be weighed after 7 days (to measure M2,t0, M2,t1, and M2,t2) after dabbing the surface water with a filter paper.
• The water uptake (swelling) will be calculated as follows (all three samples): WU (%) = [100 × (M2,t – M1,t) / M1,t]
• The surface energy and water contact angle for these hydrogels will be measured and compared.
• Once the team reports were submitted (part I), the collected data by all teams will be uploaded to Canvas to allow students to perform statistical analysis (mean, standard deviation, and t-test).

Financial Information

Total Amount Requested: $15,000

Budget Details:

Quote 1 ($15,000) Surface Characterization Device (Option 1) https://www.biolinscientific.com/hubfs/Pdf/Attension/Extranet/Marketing%20Materials/Brochures/Product%20Brochures/Attension-Theta-Range-Optical-Tensiometers-Brochure-2020%20for%20web.pdf

Quote 2 ($15,000) Surface Characterization Device (Option 2) https://www.kruss-scientific.com/en/products-services/products/dsa25e#

Please address how, if at all, this project aligns with University, Divisional, Departmental or Center strategic goals:

• Miami has identified healthcare (e.g., the medical device industry) as a field of interest. Our students have been hired by leading medical device companies in the past few years.
• A key element of Miami's strategic planning is to "advance knowledge in the professional fields considered most in-demand throughout Ohio, the region and the nation."
• As described in this proposal, the course and its labs will help to "Prepare students with the versatile skills and mindset to meet the needs of a demanding and dynamic workforce".
• The 3D scaffolds prepared in the independent studies are the continuation of a recent study funded by the National Institute of Health. Hence, the proposed application could help to "Advance Miami’s reputation for excellence and innovation in broad, transdisciplinary areas of research and pedagogy."