_ A dramatic illustration of the fact that in nanotechnology size and shape can sometimes be functional per se comes from recent work on stem cells. Stem cells can be induced to develop into very different cells, simply by growing them on a technical surface with nanoscale pits arranged in different patterns. For example "On a flower shape you get the majority of cells turning to fat, and on a star shape you've got the majority of cells turning into bone." 

This is a fascinating new twist on the geometry of nature, a subject pioneered by the great maverick biologist D’Arcy Wentworth Thompson at the beginning of the 20th century. The reason that shaped substrates can have such a dramatic effect relates to the tensegrity structure of cells. Cells maintain their shape through subtle interactions between internal structural elements, the cell membrane, and external forces acting on the cell. The stem cells “read” the patterns on the technical surface and respond in a biological way: a fascinating organic/inorganic interaction. 

Ref: Nature Materials 10, 559–560 (2011)

 

Google Analytics Yahoo