Biophysics research today is comprised of several specific biological studies which neither share a unique identifying factor nor subject themselves to clear and concise definitions. The studies included under the umbrella of biophysics range from sequence analysis to neural networks. Biophysics is also concerned with creating mechanical limbs and nanomachines to regulate biological functions, although currently these are more commonly referred to as belonging to the fields of bioengineering and nanotechnology respectively.
Biophysics typically addresses biological questions that are similar to those in biochemistry, but the questions are asked at a molecular level. Traditional studies in biochemistry and molecular biology are conducted using statistical ensemble experiments, typically using pico- to micro-molar concentrations of macromolecules. Because the molecules that comprise living cells are so small, techniques such as PCR amplification, gel blotting, fluorescence labeling and in vivo staining are used so that experimental results are observable with an unaided eye or, at most, optical magnification. Using these techniques, researchers in these subjects attempt to elucidate the complex systems of interactions that give rise to the processes that make life possible. By drawing knowledge and experimental techniques from a wide variety of disciplines, biophysicists are able to indirectly observe or model the structures and interactions of individual molecules or complexes of molecules.
In addition to things like deciphering a protein structure or measuring the kinetics of interactions, biophysics is also understood to encompass research areas that apply models and experimental techniques derived from physics (e.g. electromagnetism and quantum mechanics) to larger systems such as tissues or organs (hence the inclusion of basic neuroscience as well as more applied techniques such as fMRI).
Focus as a subfield
Biophysics often does not have university-level departments of its own, but have presence as groups across departments within the fields of biology, biochemistry, chemistry, computer science, mathematics, medicine, pharmacology, physiology, physics, and neuroscience. What follows is a list of examples of how each department applies its efforts toward the study of biophysics. This list is hardly all inclusive. Nor does each subject of study belong exclusively to any particular department. Each academic institution makes its own rules and there is much mixing between departments.
Carlos Bustamante, known for single-molecule biophysics of molecular motors and biological polymer physics
Steven Chu, Nobel Laureate who helped develop optical trapping techniques used by many biophysicists
Friedrich Dessauer, research on radiation, especially X-rays
John J. Hopfield, worked on error correction in Transcription and Translation (kinetic proof-reading), and associative memory models (Hopfield net)
Martin Karplus, research on molecular dynamical simulations of biological macromolecules.
Franklin Offner, professor emeritus at Northwestern University of professor of biophysics, biomedical engineering and electronics who developed a modern prototype of the electroencephalograph and electrocardiograph called the dynograph
Mikhail Volkenshtein, Revaz Dogonadze & Zurab Urushadze, authors of the 1st Quantum-Mechanical (Physical) Model of Enzyme Catalysis, supported a theory that enzyme catalysis use quantum-mechanical effects such as tunneling.
John P. Wikswo, research on biomagnetism
Douglas Warrick, specializing in bird flight (hummingbirds and pigeons)