The characterization of molecular structure, the measurement of molecular properties, and the observation of molecular behavior presents an enormous challenge for biological scientists. A wide range of biophysical techniques have been developed to study molecules in crystals, in solution, in cells, and in organisms. These biophysical techniques provide information about the electronic structure, size, shape, dynamics, polarity, and modes of interaction of biological molecules. Some of the most exciting techniques provide images of cells, subcellular structures, and even individual molecules. It is now possible, for example, to directly observe the biological behavior and physical properties of single protein or DNA molecules within a living cell and determine how the behavior of the single molecule influences the biological function of the organism.
Much biophysical research involves either the development of novel techniques to investigate the structure, properties, and biological functions of biomolecules or the application of these techniques to monitor how the structure and dynamics of biomolecules enables specific biological functions. Information about specific biophysical techniques is provided here.
The behavior of large biomolecules—proteins, carbohydrates, and nucleic acids—in solution is complex and directly related to molecular size, shape, and flexibility; the analysis of hydrodynamic behavior thus provides important information about the structure, dynamics, and interactions of biomacromolecules.
Perhaps the most accessible developments in biophysics have involved improvements in our ability to generate images of cellular and molecular structures with dimensions from microns to nanometers. It is now possible to “see” individual molecules or cellular structures using atomic force, electron, or confocal fluorescence microscopy.
Visual and numerical modeling and simulation play important roles in the analysis and prediction of protein and nucleic acid sequence and 3D structure, in the calculation of molecular dynamics, and in the simulation of specific biochemical mechanisms, among other important tasks.
Perhaps the most exciting development in biophysical technique in recent times involves the ability to manipulate single molecules and measure their properties and biological functions both in solution and within cells.
The interaction of electromagnetic radiation, x-rays, ultraviolet, visible, and infra red light, and radio waves, with molecules provides a wealth of information about the structure, dynamics, and function of biomolecules and biological processes.