Counter-propagating dual-trap optical tweezers based on linear momentum conservation
Author
Ribezzi-Crivellari, M.
Huguet Casades, Josep Maria
Ritort, F.
Publication date
2013ISSN
0034-6748
Abstract
We present a dual-trap optical tweezers setup which directly measures forces using linear momentum conservation. The setup uses a counter-propagating geometry, which allows momentum measurement on each beam separately. The experimental advantages of this setup include low drift due to all-optical manipulation, and a robust calibration (independent of the features of the trapped object or buffer medium) due to the force measurement method. Although this design does not attain the high-resolution of some co-propagating setups, we show that it can be used to perform different single molecule measurements: fluctuation-based molecular stiffness characterization at different forces and hopping experiments on molecular hairpins. Remarkably, in our setup it is possible to manipulate very short tethers (such as molecular hairpins with short handles) down to the limit where beads are almost in contact. The setup is used to illustrate a novel method for measuring the stiffness of optical traps and tethers on the basis of equilibrium force fluctuations, i.e., without the need of measuring the force vs molecular extension curve. This method is of general interest for dual trap optical tweezers setups and can be extended to setups which do not directly measure forces.
Document Type
Article
Document version
Published version
Language
English
Subject (CDU)
611 - Anatomy. Human and comparative anatomy
Keywords
Mecánica newtoniana
Ruido electrónico
Fibra óptica
Óptica geométrica
Propiedades ópticas
Pinzas ópticas
Autoenfoque
Trampa óptica
Física láser
Técnicas de molécula única
Mecànica newtoniana
Soroll electrònic
Fibra òptica
Òptica geomètrica
Propietats òptiques
Pinces òptiques
Autoenfocament
Trampa òptica
Física làser
Tècniques de molècula única
Newtonian mechanics
Electronic noise
Fiber optics
Geometrical optics
Optical properties
Optical tweezers
Self focusing
Optical trapping
Laser physics
Single molecule techniques
Pages
Desconocido
Publisher
AIP Publishing
Collection
84
Is part of
Review of Scientific Instruments
Citation
Ribezzi-Crivellari, M.; Huguet Casades, Josep Maria; Ritort, F. Counter-propagating dual-trap optical tweezers based on linear momentum conservation. Review of Scientific Instruments, 2013, 84, 043104. Disponible en: <https://pubs.aip.org/aip/rsi/article-abstract/84/4/043104/358115/Counter-propagating-dual-trap-optical-tweezers?redirectedFrom=fulltext>. Fecha de acceso: 18 mar. 2024. DOI: 10.1063/1.4799289
This item appears in the following Collection(s)
- Ciències Bàsiques [65]
Rights
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