On Tweaking the Mineral-Organic Interface: Bottom-up Engineering of Crystalline Materials

Many biological materials found in Nature are tough and strong—examples of the mineralized kind range from sea shells to bones and teeth. These biological materials serve as examples of complex, functional materials that are constructed from organic and inorganic components. In order to create proper conditions for growth and development, biology has adapted mechanisms to sequester and organize local chemical environments. These include processes that regulate pH, concentration, and organic-inorganic interactions—all necessary events for proper cellular and mineralized tissue growth processes.

Recent evidence reveal the presence of nanoscale mineral precursors that are intermediate phases in mineralization; clustering into assemblies that template for nucleation events. Several groups have shown that interactions with these intermediate phases drive mineralization along diverse pathways. These intermediate phases support the existence of a non-classical route to crystallization.

We demonstrate that specific macromolecules found in Nature interact with these intermediate phases to select crystal polymorphs and form unique bulk crystalline arrangements. By regulating these interactions through physico-chemical and microfluidic methods, we show that these macromolecules alter local ion supersaturation to drive mineralization along pathways that form specific mineral-organic assemblies. The characteristics of these assemblies are crucial in their regulation of nanoscale processes such as nucleation and crystal growth mechanisms. With these observations, we can begin to formulate approaches that utilize these biological strategies in creating synthetic, bulk functional crystalline materials with tunable materials properties.

Biography:

Jong Seto’s research interests are focused on engineering the mineral-organic interface to create novel biomimetic materials as well as to address related musculoskeletal and dental disorders for improved human health. His work utilizes in situ and microfluidic methods to investigate the role of specific macromolecules in modulating processes of self-assembly and organization in hierarchical, biomineralized tissues—from the molecular to the tissue length-scales. Jong received his B.S. in Bioengineering from the University of California, Berkeley in 2002. He completed his Ph.D. at the Max-Planck-Institute of Colloids and Interfaces in 2010. He has received an EU Marie Curie Fellowship (2008) and Foundation Pierre-Gilles De Gennes Fellowship (2013) to support his research. He is currently in the Department of Bioengineering and Therapeutic Sciences at the University of California, San Francisco.