Nanofabrication in cellular engineering

Biological cells are strongly influenced by the topography of the surface on which they live, both in cell culture and in an animal. They are guided along micron sized grooves and change their shape becoming more elongated. On the other hand, cells do not adhere to surfaces that are covered in small nanometrically sized pillars. These effects can be used for cellular engineering purposes to determine the behavior of cells and in particular to make prostheses for medical purposes. The differences in micro and nanofabrication techniques necessary to adapt normal semiconductor technology for these purposes are discussed. Patterning of plastics using mechanical methods (embossing and molding) is shown to have excellent resolution, can be used on biodegradable material and a large enough area of patterned material can be produced at a reasonable cost. An application of this technology to the repair of broken tendons is discussed in some detail. It is shown that a biodegradable membrane patterned by embossing with a fused silica master can be used to effect tendon repair. Not only does the tendon reheal, but the synovial channel that should surround the tendon and provide lubrication to the tendon, is reformed correctly. (C) 1998 American Vacuum Society. [S0734-211X(98)14506-7].