Brookhaven Lecture

Some of the hardest and sturdiest materials are not made in the factory; they are made inside the bodies of animals through a process called biomineralization. Look no further than your refrigerator for one of the simplest products of this natural construction company: a chicken's eggshell. Made out of just about a half-millimeter of layered calcium carbonate and protein, eggshells might be thought of as fragile, but they also provide vital protection for the chick forming inside. <p> Biomineralization, the process by which organisms form materials such as bones, mollusk shells, and other structures, has captured the attention of scientists for years. The cells in an animal's body have special ways of controlling the sizes and shapes of these mineral compounds and incorporating organic materials into the mix, making many materials that are stronger, harder, and more wear-resistant than rocks. Finding a way to mimic the properties of these sturdy and naturally made materials could lead to the medical engineering of replacement bone, teeth, and cartilage, as well as the development of new electronic and industrial materials. <p> With collaborators at Stony Brook University, physicist Elaine DiMasi develops different biomineralization models, including a protein network that resembles real tissue. Then, the researchers use x-rays at the NSLS and a technique called shear modulation force microscopy to determine what biominerals look like and how they grow. In particular, DiMasi is interested in studying some of the earliest stages of biomineralization to find out what sets the process in motion.