Touch the Invisible is a free and open-source educational resource intended to help students learn about complex biological macromolecules. While the main resources for this project are the 3D printed molecular structures that students can interact with in a classroom, the team here at Touch the Invisible recognizes that not everyone has access to the physical models all the time. In addition to providing instructions and the files used to 3D print the models, Touch the Invisible hosts a catalog of supplementary materials that can be used in conjunction with physical models or by themselves. Some of the resources are described below.

Figure Sheets

The same macromolecule can be represented in a multitude of different ways (e.g. ribbon model, surface model, etc.), with each representation highlighting different but important aspects of the molecules. It is not realistic to 3D print every representation of every molecule, so these figure sheets provide additional representations for students to view and learn from.

Digital Models

Students likely do not have access to physical models outside of the classroom, so these digital models act as a good substitute for them to still interact with the models and learn. Digital models can be manipulated just as you would a physical model, with the added benefit that more representations can be created. Currently, digital models exist for every representation found on the Figure Sheets for each molecule.


Infographics are a very good way to introduce each model. They offer a concise and easy way to digest the important points for each molecule so students can have a basic understanding of what they are working with.


Our videos offer additional ways to learn about each molecule, with each video featuring rotating models with additional educational information.

See videos here

Physical Models

Currently, our catalog of models includes the following:

We are always looking to expand our catalog of models and library of educational resources, so let us know what you would like to see by leaving a message on our contact page.

3D Printing Manual

Access the manual here

Future Directions

We are constantly looking to expand our catalog of models and our reach. If you are interested in getting involved with Touch the Invisible or looking to implement some of these models at your own university/school, please contact either Zuzana Swigonova at zus3@pitt.edu or Richard Fang at richardfang@pitt.edu.