Abstract

We report near-optimal tracking of freely diffusing fluorescent particles in a quasi-two-dimensional geometry via photon counting and real-time feedback. We present a quantitative statistical model of our feedback network and find excellent agreement with the experiment. We monitor the motion of a single fluorescent particle with a sensitivity of $15\mathrm{nm}∕\sqrt{\mathrm{Hz}}$ while collecting fewer than $5000\text{fluorescence}\text{photons}∕\mathrm{s}$. Fluorescent microspheres (diffusion coefficient $1.3\mu {\mathrm{m}}^2∕\mathrm{s}$) are tracked with a root-mean-square tracking error of $170\mathrm{nm}$, within a factor of 2 of the theoretical limit set by photon counting shot noise.

© 2006 Optical Society of America

Fluctuations in closed-loop fluorescent particle tracking

Andrew J. Berglund, Kevin McHale, and Hideo Mabuchi
Opt. Express 15(12) 7752-7773 (2007)

Tracking-FCS: Fluorescence correlation spectroscopy of individual particles

Andrew J. Berglund and Hideo Mabuchi
Opt. Express 13(20) 8069-8082 (2005)

Shot-noise limited localization of single 20 nm gold particles with nanometer spatial precision within microseconds

Ying-Hsiu Lin, Wei-Lin Chang, and Chia-Lung Hsieh
Opt. Express 22(8) 9159-9170 (2014)

Highly sensitive spectral interferometric four-wave mixing microscopy near the shot noise limit and its combination with two-photon excited fluorescence microscopy

Keisuke Isobe, Yasuyuki Ozeki, Takehito Kawasumi, Shogo Kataoka, Shin’ichiro Kajiyama, Kiichi Fukui, and Kazuyoshi Itoh
Opt. Express 14(23) 11204-11214 (2006)

Optimal tracking of a Brownian particle

Alexander P. Fields and Adam E. Cohen
Opt. Express 20(20) 22585-22601 (2012)