CUSTOM-MADE BIOMATERIALS: Applying engineering, materials, and chemistry principles, researchers produce safe, smart, and effective implantable devices

MEDICINE AND IMPROVISATION HARDLY SEEM A LIKEly pair, but since ancient times, resourceful doctors have carried out difficult procedures, often making do with materials on hand. Wounds were sewn shut with plant fibers and animal-derived materials by ancient Egyptians and Greeks, and prosthetic limbs were fashioned from wood. Metals eventually came to be used in dentistry and early this past century, when stainless steel became available, the corrosion-resistant alloy was used to make a variety of prostheses. Like their counterparts of long ago, medical practitioners today often seek to cure ailments or improve a patient's quality of life by replacing a defective body part with a substitute. But until quite recently, physicians were limited to using off-theshelf supplies that weren't designed for the application. Early artificial hearts, for example, included polyurethanes that were derived from women's girdles because the material's good flexural properties were desirable. And a material once selected for...