Literature/202310101226 tracking magnetic beads in 3d

<ul> <li>Source: [<a class="litnote tooltip" href="/literature/@rieu2021">@rieu2021<span class="tooltiptext">Parallel, linear, and subnanometric 3D tracking of microparticles with Stereo Darkfield Interferometry</span></a>]</li> <li>Tags: <a href="/tags/magnetic-beads">#magnetic-beads</a> <a href="/tags/nanoparticle-tracking-analysis">#nanoparticle-tracking-analysis</a> </li> </ul> <p>Using <a class="wikilink" href="/stereo_darkfield_interferometry/">Stereo Darkfield Interferometry</a> (see paper: <a class="wikilink" href="/literature/202310101212_stereo_darkfield_interferometry/">Stereo Darkfield Interferometry</a>) it is possible to perform force-extension measurements by using <a class="wikilink" href="/magnetic_nanoparticles/">magnetic nanoparticles</a> under a <a class="wikilink" href="/magnetic_tweezer/">magnetic tweezer</a>. </p> <p>The biggest advantage of <em>SDI</em> is that allows for multiple particles to be tracked at once:</p> <p><img alt="images/Pasted image 20231010123220.png" class="wikiimage" src="/images/pasted image 20231010123220.png" /></p> <p>In this case, the most relevant parameter is the position along the optical axis ($\hat{z}$) which is encoded in the rotation of the intereference pattern recorded on the camera. </p> <p>Applications to DNA hybridization:</p> <p><img alt="images/Pasted image 20231010123337.png" class="wikiimage" src="/images/pasted image 20231010123337.png" /></p> <p>And helicase stepping:</p> <p><img alt="images/Pasted image 20231010123418.png" class="wikiimage" src="/images/pasted image 20231010123418.png" /></p> <p>Come as natural applications. </p> <p>It is worth noting that the presence of <a class="wikilink" href="/brownian_motion/">brownian motion</a> is the real limit to the accuracy of these measurements. <a class="wikilink" href="/magnetic_tweezer/">magnetic tweezer</a> does not have infinite stiffness. </p> <p>The <strong>temporal resolution</strong> limit of the method comes from these thermal fluctuations than from the optical resolution itself or the data-transfer rate from the camera.</p>