measured particle excursions and theoretical expectations, which helps clarify both the experiments and models of DNA conformation.\
author:
- 'LIN HAN[^1]'
- 'BERTRAND H. LUI$^{*}$[^2]'
- 'SETH BLUMBERG$^{*}$[^3]'
- 'JOHN F. BEAUSANG[^4]'
- 'PHILIP C. NELSON$^{\S}$'
- 'ROB PHILLIPS$^{*}$[^5]'
bibliography:
- 'calibrationBib.bib'
title: CALIBRATION OF TETHERED PARTICLE MOTION EXPERIMENTS
---

Tethered particle; DNA; Brownian motion; calibration; single molecule

[Primary 92C05; secondary 92C40, 92C37.]{}

Introduction
============

=Single molecule studies are enriching our understanding of biological processes by providing a unique window on the microtrajectories of individual molecules rather than their ensemble-averaged behavior. Many of these studies are devoted to exploring the intricacies of protein–DNA interactions that are central to gene regulation, DNA replication and DNA repair. The resolution of nanometer-scale distances involved in such interactions poses a significant challenge. The emergence of the tethered particle motion (TPM) method offers a practical and relatively simple solution. In this method, a biopolymer is tethered between a stationary substrate and a micrometer-scale sphere (a “bead”), which is large enough to be imaged with conventional optical microscopy (). The constrained Brownian motion of the bead serves as a reporter of the underlying macromolecular dynamics, either by observing its blurred image in a long exposure [@Finzi1995], 