All biological processes ultimately take place at the molecular level, all diseases arise at this level, and practically all drugs act at this level. Thus, there is an immense need to understand how these molecular interactions take place.
The challenge is that all current life science tools working at a molecular level either measure static structure or average binding kinetics; the crucial and often very complex mechanistic details of the underlying dynamic process of protein interactions are not revealed. Dynamic Single-Molecule analysis reveals these details.
Optical tweezers are based on the principle of light carrying momentum proportional to its energy and propagation direction. Stable optical trapping of dielectric particles (electrical insulators) occurs upon the interaction between light and the object itself. A laser beam that passes through an object and refracts alters its momentum by bending and changing direction.