Biophysical Society 66th Annual Meeting Program Guide

Connecting the mechanical properties to intramolecular dynamics is now also possible by correlating the optical tweezers measurements with single-molecule TIRF and label-free IRM imaging. All come togeth- er in a dedicated surface assay workflow that ensures the fastest time to results. Finally, the imaging module of the new LUMICKS C-Trap can be extend- ed with an integrated widefield imaging mode with single fluorophore sensitivity. This makes the new LUMICKS C-Trap the most versatile multi-user tool and enables applications in the study of not just cyto- skeletal structure and transport, but also DNA-binding proteins, protein folding, phase separation, and mechanobiology. Join our presentation to learn about the latest developments in dynam- ic single-molecule technology and what it can do for your next scientific breakthrough. Speaker Evan Gates, Application Scientist, LUMICKS 1:30 PM – 3:00 PM Chroma Technology Objective Thinking Today’s off-the-shelf microscopes are technological wonders, capable of imaging in many different modalities across a wide range of objec- tive lenses. But what if your need is more defined? This presentation will introduce you to the openFrame: an imaging platform based on optimizing for specific application(s) around the most important optic in your system: the objective lens. The presentation will begin by describing a few features that might be better optimized on a custom imager than on a traditional microscope. The openFrame allows complete control of the optical train, enabling fully telecentric designs and the ability to work with optical compo- nents from any manufacturer. For example, it is much easier to create a critical illuminator for illuminating large fields, as you are not con- stricted by the bulk of a traditional microscope frame and have direct access to the objective. Using a critical illuminator with fiber optic can result in 3 times the light intensity at your sample, with a flatter field of view than your standard liquid light guide into a commercial collima- tor. Perhaps you want to image in two colors simultaneously: you can split the colors in the body of the microscope and greatly reduce the amount of glass each optical pathway encounters. You can go further and select a different tube lens to optimize the resolution onto cam- eras with smaller pixels, to give a large field of view with a lower price and a more compact footprint. All of these options can be optimized to work with the objective used in your experiment, to capture every last photon and to match resolution and signal-to-noise requirements. In addition to being more flexible and compact, the openFrame is designed to be long-term sustainable, capable of being maintained and supported by any competent microscopist without reliance on proprietary information or specialist engineers: and future-proof, by maintaining consistent mounting flanges across all modules. Easy end- user alignment of all optical components means there is never a need to return the microscope to base for repair, and any damaged compo- nents can be replaced on site. Prof. Paul French’s Photonics Group at Imperial College London have conceived and developed this framework in conjunction with Cairn Research. Dr. Sunil Kumar from the Imperial group is both one of the inventors and an innovator of this platform. He will offer insights

into the motivation behind this new, open, platform. He will share with you the results of some of their experiments, including the inex- pensive EasySTORM TIRF (using a multimode laser), live quantitative phase imaging, Fluorescence Lifetime Imaging and Optical Projection Tomography. He will also discuss some of their approaches for autofo- cus, liquid handling and experimental control. During the talk a pair of technicians will build up an openFrame micro- scope before your eyes. After Dr. Kumar has shared his results, every- one will have the opportunity to see the system function in a number of modalities; from TIRF to fully automated 2-camera fluorescence with phase contrast. Speakers Jeremy Graham, CEO, Cairn Research Sunil Kumar, Research Associate, Imperial College London Esplanade, Room 158: Sunday, February 20 10:30 AM – 12:00 PM Axiom Optics SENSOCELL: Optical Tweezers Integrating Direct Force Spec- troscopy & Correlated Fluorescence Imaging For Extra- and Intra-Cellular Mechanobiology Optical tweezers (OT) were first applied to biology research questions in the early 90s, and since then they have been primarily used for molecu- lar biology applications. Conversely, their use in cell biology research has been greatly limited to trapping experiments intended for moving or manipulating living cells. The sparsity of quantitative experiments using OT in living cells is mainly due to the difficulties in measuring readily and accurately the forces applied by OT onto the probed samples. Here we present our distinctive OT platform SENSOCELL for Mechanobiology research, which allows users to carry out direct force measurements in vitro , in vivo or in situ. Molecules and cells can be manipulated and probed using microspheres as handles in in vitro condi- tions. Alternatively, forces can be directly applied and measured on cells (trapping cells as a whole) or inside cells, either via exogenous spherical particles or directly trapping endogenous cellular structures such as lipid vesicles, the cell membrane, the cell nucleus or other organelles. Thanks to its unique direct force sensor based on the analysis of light momen- tum changes, measurement protocols with SENSOCELL are unhindered by recurrent trap stiffness calibrations, allowing experiments to be car- ried out in an easy and speedy manner by non-expert users. The flexibility offered by SENSOCELL for controlling multiple traps (up to 256) with simultaneous force measurements increases throughput and allows advanced protocols for extra- and intra-cellular mechanics. The control software includes built-in routines that allow performing active micro-rheology measurements, clamping forces for particle tracking and creep tests or designing stress-relaxation experiments. The platform is integrated on customizable scientific inverted microscopes and can be combined with fluorescence imaging techniques such as Confocal, Spinning Disk, epi-FL or TIRF. Key applications include: • Active micro-rheology in cells and scaffolds • Cell nucleus stretching and indentation • Measurement of membrane tension • Membrane tether pulling • Microtubules and motor proteins activity • Cell-cell interactions • Cell-particle interactions • Microswimmer force dynamics

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