Calibration of optical tweezers with non-spherical probes via high-resolution detection of Brownian motion
Description
Abstract Optical tweezers are commonly used and powerful tools to perform force measurements on the piconewton scale and to detect nanometer-scaled displacements. However, the precision of these instruments relies to a great extent on the accuracy of the calibration method. A well-known calibration procedure is to record the stochastic motion of the trapped particle and compare its statistical behavior with the theory of the Brownian motion in a harmonic potential. Here we present an interactive calib... Title of program: PFMCal Catalogue Id: AEXH_v1_0 Nature of problem Calibration of optical tweezers by measuring the Brownian motion of the trapped object. The voltage-to-displacement ratio of the detection system (the inverse of the sensitivity), the stiffness of the trap and the size of the bead are obtained via the simultaneous fitting of the power spectral density (PSD), mean square displacement (MSD) and velocity autocorrelation (VAF) functions calculated from the trajectory. The calibration can be performed for non-spherical probes as well. Versions of this program held in the CPC repository in Mendeley Data AEXH_v1_0; PFMCal; 10.1016/j.cpc.2015.06.024 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)