Nanoscopic imaging of thick heterogeneous soft-matter structures in aqueous solution

Abstract

Precise nanometre-scale imaging of soft structures at room temperature poses a major challenge to any type of microscopy because fast thermal fluctuations lead to significant motion blur if the position of the structure is measured with insufficient bandwidth. Moreover, precise localization is also affected by optical heterogeneities, which lead to deformations in the imaged local geometry, the severity depending on the sample and its thickness. Here we introduce quantitative thermal noise imaging, a three-dimensional scanning probe technique, as a method for imaging soft, optically heterogeneous and porous matter with submicroscopic spatial resolution in aqueous solution. By imaging both individual microtubules and collagen fibrils in a network, we demonstrate that structures can be localized with a precision of ∼10 nm and that their local dynamics can be quantified with 50 kHz bandwidth and subnanometre amplitudes. Furthermore, we show how image distortions caused by optically dense structures can be corrected for.

Elasticity of individual protocadherin 15 molecules implicates tip links as the gating springs for hearing

“…1 E ). The probe bead was confined in a weak optical trap whose forward-scattered light we collected to determine the 3D position of the bead with subnanometer spatial resolution and 1-µs temporal resolution (20, 21). A second optical trap, displaced by a few hundred nanometers from the first, served to deliver a force stimulus (Fig.…”

Unraveling the Thousand Word Picture: An Introduction to Super-Resolution Data Analysis

“…59 While studies in live cells are motivating more general theoretical approaches borrowing heavily from statistical advances 179 now feasible due to computing power, quantitative analysis efforts have also helped identify clear challenges standing in the way of greater modeling accuracy. Novel experimental methods have begun addressing some of these challenges such as phototoxicity 6 and image distortions in thick heterogeneous samples 357 though other key challenges such as labeling density 358 and environment-dependent photophysical properties 359 remain.…”

Opto-thermoelectric nanotweezers

“…Measurements to quantify the trapping stiffness of trapped AuNSs and AgNSs at varying CTAC concentrations were performed on a previously described custom-built photonic force microscope 39 . In brief, the beam of a 1064 nm laser (Mephisto 500 mW, Coherent, CA, USA) at very low power was expanded and focused through a water immersion objective lens (UPlanSApo 60×W, Olympus, Tokyo, Japan) into the sample chamber.…”