Deconstructing and Reconstructing Oyster Cement to Create Inorganic Adhesives

Nontechnical Description:

Oyster reefs are one of the most dominant factors for keeping coastal environments healthy. These cemented structures, often kilometers long, absorb storm surge energy, filter water, and hold silt in place. Recent insights are showing that oysters construct their reef communities with a specialized adhesive (or “cement”) whose composition is markedly different from all commercial and other biological adhesives.

Given its unique composition and its ability to work in wet environments, oyster cement presents a different and largely unexplored view on what adhesives can be. Efforts planned for the current project will help to understand the nature of oyster cement and how this technology may be applied to create unique, new adhesives. Such information will be adapted here to test the ability of new cements to bond bone, which has a somewhat analogous composition and has been difficult to adhere strongly.

The interdisciplinary nature of these efforts will help to advance several fields including marine biology, biochemistry, and materials engineering. Outreach activities include working with high school students for laboratory modules in the Women in Engineering Program at Purdue University. Technical Description:

Oyster reefs are one of the most dominant factors for keeping coastal environments healthy. These cemented structures, often kilometers long, absorb storm surge energy, filter water, and hold silt in place. Recent insights are showing that oysters construct their reef communities with an adhesive (or “cement”) that is predominantly made of inorganic calcium carbonate and a minority of protein.

Such a composition stands in stark contrast to all commercial and other biological adhesives, which are made from organic polymers, polysaccharides, or proteins. Experiments described herein begin by identifying the proteins of oyster cement (Aim #1A). Expression of the identified proteins (Aim #1B) will then be used to make protein-inorganic formulations for understanding how the interplay between organics and inorganics generates adhesion (Aim #2).

These structure-function studies will help to illustrate how a material with such inorganic content can exhibit high strength adhesion. This knowledge will then be used to test a hypothesis stating that bonding of bone may be achieved with adhesives that are hard and predominantly inorganic (Aim #3). Outreach activities include working with high school students for laboratory modules in the Women in Engineering Program at Purdue University.

Taken together, this work will show how biology creates unique materials and guide the adaption of marine biological technologies to biomedical needs.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.