Expanding Your Horizons (EYH) 2013

On Saturday, March 23rd, 2013 Lorraine Leon, Emily Wonder, Sarah Perry and Eun Ji Chung conducted a workshop for about 35 Chicago-area middle school girls as part of the Expanding Your Horizons outreach program, hosted at the University of Chicago at the Kersten Physics Teaching Center. There were three sessions total, with about 6-13 girls per session.


Station 1 - Soy

Station 1: Soy. Students investigated different stiffnesses of soy biomaterials by testing different forms of tofu and creating their own soy-based hydrogels.

For our workshop this year, we focused on biologically inspired, biocompatible materials (biomaterials) for biomedical applications. We designed two sets of activities to bring the idea home: (1) soy and (2) alginate (seaweed). For the soy-based materials we brought soft, hard tofu, and lyophilized tofu to allow the students to investigate the effect of water content on material properties. Students were then able to prepare their own biomedical implants using bone and heart-shaped cookie cutters with both tofu and/or soy-hydrogels prepared from soy powder. This allowed the girls to connect the idea of mechanical properties with the design requirements for implants of various tissues.


Station 2 - Alginate

Station 2: Alginate. Cross-linked hydrogels were prepared by dropping alginate into a solution of calcium chloride. Encapsulation of glitter was achieved by pre-mixing the glitter into the alginate before cross-linking.

For alginate, we introduced the idea of cross-linking, which occurs in alginate upon the addition of the divalent cation calcium. Students prepared hydrogel spheres by adding alginate dropwise to a solution of calcium chloride. The students were able to investigate the stiffness of the hydrogels based on how long the spheres were allowed to sit in the cross-linking solution. We then introduced the ideas of encapsulation and composite materials by investigating the effect of incorporating varying sizes, shapes, and amounts of glitter. These ideas of encapsulation and composite materials are important with respect to the design and processing requirements of more complex implants, and for drug delivery or cell encapsulation for biomedical and tissue engineering applications.

  • This outreach effort was highlighted on the main IME website.