Biophysics and Biomaterials

There is a cultural gap between physics, which seeks to understand extremely simple systems, and biology, which is obliged to study the overall behavior of extremely complex systems. One area where simplicity and life intersect is the study of biomembranes, both in isolation and as active elements of cells. In recent years amazing new experimental techniques, including optical tweezers, have opened up the study of both the equilibrium conformations and dynamic response of membranes to quantitative analysis. Similarly the DNA molecule, while architecturally complex, has remarkably simple elastic behavior governed by just a few parameters. Apart from their potential relevance to biology, the study of these systems has revealed new physical phenomena characteristic of the highly-fluctuating micron world. At UPenn we currently have groups developing the theory of lipid bilayers, the physics of single DNA molecules, as well as the structure of condensed DNA in vitro and in vivo.