Open AccessShot-noise limited localization of single 20 nm gold particles with nanometer spatial precision within microseconds
Author(s) -
Ying-Hsiu Lin,
Wei-Lin Melody Chang,
ChiaLung Hsieh
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.009159
Subject(s) - microsecond , optics , materials science , shot noise , noise (video) , microscopy , temporal resolution , tracking (education) , nanometre , scattering , interferometry , physics , detector , computer science , psychology , pedagogy , artificial intelligence , image (mathematics)
Single-particle tracking (SPT) is a powerful approach to investigate dynamics without ensemble average. Continuing effort has been made to track smaller particles with better spatial precision at higher speed. In this work, we demonstrate SPT of 20 nm gold nanoparticle (GNP) with 2 nm spatial precision up to 500 kHz by using microsecond interferometric scattering (μs-iSCAT) microscopy. The linear scattering signal from single GNPs is detected by a high-speed CMOS camera via interference. Through this homodyne detection, shot-noise limited sensitivity, and therefore optimal localization precision are achieved at high speed where considerable electronic noise is present. Using μs-iSCAT microscopy, we observe anomalous diffusion of GNPs labeled to lipid molecules in a supported bilayer membrane prepared on a glass substrate. The combination of nanometer spatial precision and microsecond temporal resolution provides the opportunity to study rapid motions of nano-objects on molecular scale with unprecedented clarity.