An Adaptive Anti-Brownian Electrokinetic Trap with Real-Time Information on Single-Molecule Diffusivity and Mobility
- 25 May 2011
- journal article
- Published by American Chemical Society (ACS) in ACS Nano
- Vol. 5 (7), 5792-5799
- https://doi.org/10.1021/nn2014968
Abstract
We present the design and implementation of an adaptive Anti-Brownian ELectrokinetic (ABEL) trap capable of extracting estimates of the diffusion coefficient and mobility of single trapped fluorescent nanoscale objects such as biomolecules in solution. The system features rapid acousto-optic scanning of a confocal excitation spot on a 2D square lattice to encode position information on the arrival time of each detected photon, and Kalman filter-based signal processing unit for refined position estimation. We demonstrate stable trapping of multisubunit proteins (D ≈ 22 μm2/s) with a count rate of 6 kHz for as long as 15 s and small single-stranded DNA molecules (D ≈ 118 μm2/s) at a 15 kHz count rate for seconds. Moreover, we demonstrate real-time measurement of diffusion coefficient and electrokinetic mobility of trapped objects, using adaptive tuning of the Kalman filter parameters.This publication has 31 references indexed in Scilit:
- Three-Dimensional Tracking of Single Fluorescent Particles with Submillisecond Temporal ResolutionNano Letters, 2010
- Geometry-induced electrostatic trapping of nanometric objects in a fluidNature, 2010
- The corral trap: fabrication and software developmentPublished by SPIE-Intl Soc Optical Eng ,2010
- Localizing and Tracking Single Nanoscale Emitters in Three Dimensions with High Spatiotemporal Resolution Using a Double-Helix Point Spread FunctionNano Letters, 2009
- 3D Particle Trajectories Observed by Orthogonal Tracking MicroscopyACS Nano, 2009
- Optical manipulation of nanoparticles and biomolecules in sub-wavelength slot waveguidesNature, 2009
- Three-dimensional tracking of individual quantum dotsApplied Physics Letters, 2007
- Feedback localization of freely diffusing fluorescent particles near the optical shot-noise limitOptics Letters, 2006
- Confocal three dimensional tracking of a single nanoparticle with concurrent spectroscopic readoutsApplied Physics Letters, 2006
- Single Molecule Detection in SolutionPublished by Wiley ,2002