Undergraduate Ecosystems: Engineering Tissues with 3D Printers
INSTRUCTIVE BIOMATERIALS AND ADDITIVE MANUFACTURING LABORATORY
Despite significant efforts, the lack of organs and tissues for transplantation poses a major hurdle in medicine. The Instructive Biomaterials and Additive Manufacturing Laboratory (IBAM-Lab) develops novel approaches to address this gap. The lab designs biodegradable polymers and hydrogels with userdefined and tunable properties; engineers medical devices, tissues and organs using 3D-bioprinting; develops material-based technologies to control stem cell differentiation; and fabricates patient-specific in vitro disease models for fundamental studies and drug screening. Additionally, IBAM-Lab devises novel strategies for biomimetic material design, stimuli-responsive materials, surface patterning and photopolymerization. The facility includes a wet lab designed for polymer discovery, synthesis and processing, and a biolab for elucidating cell-material interactions in vitro.
“My students and I take a multidisciplinary approach toward developing innovative treatment alternatives using novel biomaterials with 3D-bioprinting, including the biofabrication of tissues and the development of tissue-engineered scaffolds and medical devices," says Murat Guvendiren, assistant professor of chemical and materials engineering and the lab's director. "I am particularly motivated to develop mini projects designed for undergraduate students, which are parts of much larger projects. I also encourage them to do fun stuff such as printing chocolate.”
BIOPRINTING BLOOD VESSEL NETWORKS
Emily Almeida ’18 is 3D bioprinting vascular networks using hydrogels. Within the context of tissue engineering, networks of blood vessels will be “essential to allow nutrient transportation and waste removal in cells,” she says. Prior to printing, she tested several parameters to achieve the desired mechanical properties and dimensions. Once the final scaffold was printed, she incorporated cells and growth factors into the matrix. Of the lab, she notes, “We’re all working on different aspects that will at some point come together in a human mimetic prototype.”
BRIDGING THE INTERFACE BETWEEN CARTILAGE AND BONE
Using computer-aided design and a 3D printer, Hazal Yalcin ’18 is designing a gradient scaffold to help knit together damaged bone and cartilage at the interface where the two tissues rub against each other and wear each other down. “Bone and cartilage are two different tissues with different properties, so in order for them to heal at the same time, I’m creating two scaffolds and combining them. I then test them under mechanical forces to see what sort of patterns bear the load best,” she says, adding, “It’s really useful – and interesting – to see how tissue regenerates.”
FORMING WRINKLES ON 3D-PRINTED HYDROGELS
Using a 3D bioplotter, Jorge Pereyra ’18 is creating wrinkle patterns on hydrogels – some wavy and random and some highly ordered hexagonals – which he then layers into a three-dimensional matrix to support cell growth. “We’ll study the behavior of cells in these different patterns,” he says, “and try to determine where they grow best.” But there are many other potential applications for printed hydrogels, he adds, including adhesives, microdevices and sensors. For insurance purposes, for example, a company could coat a cellphone with material that “wrinkled when it came in contact with water.”
