title: Exact Theory of Optical Tweezers and Its Application to Absolute Calibration.
abstract: Optical tweezers have become a powerful tool for basic and applied research in cell biology. Here, we describe an experimentally verified theory for the trapping forces generated by optical tweezers based on first principles that allows absolute calibration. For pedagogical reasons, the steps that led to the development of the theory over the past 15 years are outlined. The results are applicable to a broad range of microsphere radii, from the Rayleigh regime to the ray optics one, for different polarizations and trapping heights, including all commonly employed parameter domains. Protocols for implementing absolute calibration are given, explaining how to measure all required experimental parameters, and including a link to an applet for stiffness calculations.
authors.affiliation: Instituto Federal de Educação, Ciência e Tecnologia, Rua Sebastião de Lacerda, Paracambi, RJ, 26600-000, Brazil.|Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
authors.forename: Rafael S
authors.initials: RS
authors.lastname: Dutra
authors.affiliation: Instituto de Física and LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ, 21941-972, Brazil.
authors.forename: Nathan B
authors.initials: NB
authors.lastname: Viana
authors.affiliation: Instituto de Física and LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ, 21941-972, Brazil.
authors.forename: Paulo A Maia
authors.initials: PAM
authors.lastname: Neto
authors.affiliation: Instituto de Física and LPO-COPEA, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ, 21941-972, Brazil.
authors.forename: H Moysés
authors.initials: HM
authors.lastname: Nussenzveig
mesh_terms: D002138:Calibration; D008962:Models, Theoretical; D052898:Optical Tweezers; D055095:Optics and Photonics
keywords: Absolute calibration; Optical trap forces; Optical tweezers