Definition
An optical trap is a device that uses a focused laser beam to create a potential well, in which a small object (100 nm to a few micrometers) whose refractive index is greater than that of the surrounding fluid can be trapped. The object experiences a restoring force that is directed toward the center of the potential well, which is directly proportional to the distance of the object from the center of the potential well. An optical trap can be used to apply piconewton forces to biological marcomolecules such as proteins and DNA. A dual-beam optical tweezer consists of two focused laser beams that are used to trap two different objects and move them independently in solution. A common biological application of the dual-beam optical tweezer is the measurement of the biophysical properties of molecular motors.
Basic Concept of an Optical Trap
Light has momentum and a force is generated when the...
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© 2013 European Biophysical Societies' Association (EBSA)
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Sivaramakrishnan, S., Sung, J.M., Dunn, A.R., Spudich, J.A. (2013). Dual-Beam Optical Tweezers. In: Roberts, G.C.K. (eds) Encyclopedia of Biophysics. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-16712-6_514
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DOI: https://doi.org/10.1007/978-3-642-16712-6_514
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