scholarly journals Mid-infrared optoacoustic microscopy with label-free chemical contrast in living cells and tissues

2018 ◽  
Author(s):  
Miguel A. Pleitez ◽  
Asrar Ali Khan ◽  
Josefine Reber ◽  
Andriy Chmyrov ◽  
Markus R. Seeger ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Living Cells ◽  
Spatiotemporal Dynamics ◽  
Live Cell ◽  
Imaging Modalities ◽  
Label Free ◽  
Infrared Microscopy ◽  
Mid Infrared ◽  
Infrared Sensing ◽  
Biomolecular Imaging

We developed mid-infrared optoacoustic microscopy (MiROM), a bond-selective imaging modality that overcomes water/tissue opacity and depth limitations of mid-infrared sensing allowing uncompromised live-cell/thick-tissue mid-infrared microscopy with up to three orders of magnitudehigher sensitivity than other vibrational imaging modalities; such as Raman. We showcase the functional label-free biomolecular imaging capabilities of MiROM by monitoring the spatiotemporal dynamics of lipids and proteins during lipolysis in living adipocytes. Since MiROM, contrary to Ramanmodalities, is not only able to detect lipids and proteins, but also important metabolites such as glucose without the need of labels, here we discuss how MiROM yields novel functional label-free abilities for a broader range of analytical studies in living cells and tissues.

Advancements in quantum cascade laser-based infrared microscopy of aqueous media

2016 ◽  
Vol 187 ◽  
pp. 119-134 ◽  
Author(s):  
K. Haase ◽  
N. Kröger-Lui ◽  
A. Pucci ◽  
A. Schönhals ◽  
W. Petrich
Keyword(s):  
Quantum Cascade Laser ◽  
Quantum Cascade Lasers ◽  
Spectral Power ◽  
Aqueous Media ◽  
Aqueous Environment ◽  
Label Free ◽  
Infrared Microscopy ◽  
Signal To Noise ◽  
Mid Infrared ◽  
Quantum Cascade

The large mid-infrared absorption coefficient of water frequently hampers the rapid, label-free infrared microscopy of biological objects in their natural aqueous environment. However, the high spectral power density of quantum cascade lasers is shifting this limitation such that mid-infrared absorbance images can be acquired in situ within signal-to-noise ratios of up to 100. Even at sample thicknesses well above 50 μm, signal-to-noise ratios above 10 are readily achieved. The quantum cascade laser-based microspectroscopy of aqueous media is exemplified by imaging an aqueous yeast solution and quantifying glucose consumption, ethanol generation as well as the production of carbon dioxide gas during fermentation.

scholarly journals Ultra-wideband enhancement on mid-infrared fingerprint sensing for 2D materials and analytes of monolayers by a metagrating

Nanophotonics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 2927-2935
Author(s):  
Yinong Xie ◽  
Xueying Liu ◽  
Fajun Li ◽  
Jinfeng Zhu ◽  
Naixing Feng
Keyword(s):  
Trace Amount ◽  
2D Materials ◽  
Polarized Light ◽  
Ultra Wideband ◽  
Label Free ◽  
Infrared Band ◽  
Mid Infrared ◽  
Infrared Sensing ◽  
New Applications ◽  
Non Destructive

AbstractMid-infrared absorption spectroscopy is a powerful tool to identify analytes by detecting their material fingerprint in a label-free way, but it faces barriers on trace-amount analysis due to the difficulties in enhancing the broadband spectral signals. Here, we propose a sensing scheme based on the angular scanning of polarized light on a dielectric metagrating, and demonstrate it by numerical simulation. This approach not only indicates a series of significant signal enhancement factors over 30 times in an ultra-wide mid-infrared band, but also enables the explicit identification for various analytes, including 2D materials and trace-amount thin film samples. Our method would facilitate mid-infrared sensing for 2D materials and trace-amount analysis, and enable many new applications on non-destructive molecular identification.

A protocol for rapid, label-free histochemical imaging of fibrotic liver

The Analyst ◽  
2017 ◽  
Vol 142 (8) ◽  
pp. 1179-1184 ◽  
Author(s):  
B. Bird ◽  
J. Rowlette
Keyword(s):  
High Throughput ◽  
Imaging Technique ◽  
Spectroscopic Imaging ◽  
Label Free ◽  
Biochemical Screening ◽  
Infrared Microscopy ◽  
Fibrotic Liver ◽  
Mid Infrared ◽  
Non Destructive

Mid-infrared microscopy is a non-destructive, quantitative and label-free spectroscopic imaging technique that, as a result of recent instrument advancements, is now at the point of enabling high-throughput automated biochemical screening of whole histology samples.

scholarly journals Depth-resolved mid-infrared photothermal imaging of living cells and organisms with submicrometer spatial resolution

2016 ◽  
Vol 2 (9) ◽  
pp. e1600521 ◽  
Author(s):  
Delong Zhang ◽  
Chen Li ◽  
Chi Zhang ◽  
Mikhail N. Slipchenko ◽  
Gregory Eakins ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Single Cells ◽  
Chemical Imaging ◽  
Detection Sensitivity ◽  
Living Systems ◽  
Live Cells ◽  
Photothermal Effect ◽  
Label Free ◽  
Infrared Microscopy ◽  
Mid Infrared

Chemical contrast has long been sought for label-free visualization of biomolecules and materials in complex living systems. Although infrared spectroscopic imaging has come a long way in this direction, it is thus far only applicable to dried tissues because of the strong infrared absorption by water. It also suffers from low spatial resolution due to long wavelengths and lacks optical sectioning capabilities. We overcome these limitations through sensing vibrational absorption–induced photothermal effect by a visible laser beam. Our mid-infrared photothermal (MIP) approach reached 10 μM detection sensitivity and submicrometer lateral spatial resolution. This performance has exceeded the diffraction limit of infrared microscopy and allowed label-free three-dimensional chemical imaging of live cells and organisms. Distributions of endogenous lipid and exogenous drug inside single cells were visualized. We further demonstrated in vivo MIP imaging of lipids and proteins inCaenorhabditis elegans. The reported MIP imaging technology promises broad applications from monitoring metabolic activities to high-resolution mapping of drug molecules in living systems, which are beyond the reach of current infrared microscopy.

scholarly journals Label-free metabolic imaging by mid-infrared optoacoustic microscopy in living cells

2019 ◽  
Vol 38 (3) ◽  
pp. 293-296 ◽  
Author(s):  
Miguel A. Pleitez ◽  
Asrar Ali Khan ◽  
Alice Soldà ◽  
Andriy Chmyrov ◽  
Josefine Reber ◽  
...  
Keyword(s):  
Living Cells ◽  
Metabolic Imaging ◽  
Label Free ◽  
Mid Infrared

scholarly journals Impact of the COVID-19 pandemic on the selection of chest imaging modalities and reporting systems: a survey of Italian radiologists

2021 ◽  
Author(s):  
Andrea Borghesi ◽  
Nicola Sverzellati ◽  
Roberta Polverosi ◽  
Maurizio Balbi ◽  
Elisa Baratella ◽  
...  
Keyword(s):  
Continuing Education ◽  
Reporting System ◽  
Imaging Modality ◽  
Diagnostic Technique ◽  
Imaging Modalities ◽  
Chest Imaging ◽  
Reporting Systems ◽  
Imaging Approach ◽  
Narrative Report ◽  
Selection Of

Abstract Purpose Chest imaging modalities play a key role for the management of patient with coronavirus disease (COVID-19). Unfortunately, there is no consensus on the optimal chest imaging approach in the evaluation of patients with COVID-19 pneumonia, and radiology departments tend to use different approaches. Thus, the main objective of this survey was to assess how chest imaging modalities have been used during the different phases of the first COVID-19 wave in Italy, and which diagnostic technique and reporting system would have been preferred based on the experience gained during the pandemic. Material and Methods The questionnaire of the survey consisted of 26 questions. The link to participate in the survey was sent to all members of the Italian Society of Medical and Interventional Radiology (SIRM). Results The survey gathered responses from 716 SIRM members. The most notable result was that the most used and preferred chest imaging modality to assess/exclude/monitor COVID-19 pneumonia during the different phases of the first COVID-19 wave was computed tomography (51.8% to 77.1% of participants). Additionally, while the narrative report was the most used reporting system (55.6% of respondents), one-third of participants would have preferred to utilize structured reporting systems. Conclusion This survey shows that the participants’ responses did not properly align with the imaging guidelines for managing COVID-19 that have been made by several scientific, including SIRM. Therefore, there is a need for continuing education to keep radiologists up to date and aware of the advantages and limitations of the chest imaging modalities and reporting systems.

Applying label-free dynamic mass redistribution technology to frame signaling of G protein–coupled receptors noninvasively in living cells

2011 ◽  
Vol 6 (11) ◽  
pp. 1748-1760 ◽  
Author(s):  
Ralf Schröder ◽  
Johannes Schmidt ◽  
Stefanie Blättermann ◽  
Lucas Peters ◽  
Nicole Janssen ◽  
...  
Keyword(s):  
G Protein ◽  
Living Cells ◽  
G Protein Coupled Receptors ◽  
Label Free ◽  
Dynamic Mass ◽  
Mass Redistribution ◽  
G Protein Coupled ◽  
Free Dynamic

scholarly journals Live-cell imaging reveals the spatiotemporal organization of endogenous RNA polymerase II phosphorylation at a single gene

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Linda S. Forero-Quintero ◽  
William Raymond ◽  
Tetsuya Handa ◽  
Matthew N. Saxton ◽  
Tatsuya Morisaki ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Single Molecule ◽  
Computational Models ◽  
Spatial Organization ◽  
Fluorescent Antibody ◽  
Single Gene ◽  
Single Copy ◽  
Living Cells ◽  
Live Cell

AbstractThe carboxyl-terminal domain of RNA polymerase II (RNAP2) is phosphorylated during transcription in eukaryotic cells. While residue-specific phosphorylation has been mapped with exquisite spatial resolution along the 1D genome in a population of fixed cells using immunoprecipitation-based assays, the timing, kinetics, and spatial organization of phosphorylation along a single-copy gene have not yet been measured in living cells. Here, we achieve this by combining multi-color, single-molecule microscopy with fluorescent antibody-based probes that specifically bind to different phosphorylated forms of endogenous RNAP2 in living cells. Applying this methodology to a single-copy HIV-1 reporter gene provides live-cell evidence for heterogeneity in the distribution of RNAP2 along the length of the gene as well as Serine 5 phosphorylated RNAP2 clusters that remain separated in both space and time from nascent mRNA synthesis. Computational models determine that 5 to 40 RNAP2 cluster around the promoter during a typical transcriptional burst, with most phosphorylated at Serine 5 within 6 seconds of arrival and roughly half escaping the promoter in ~1.5 minutes. Taken together, our data provide live-cell support for the notion of efficient transcription clusters that transiently form around promoters and contain high concentrations of RNAP2 phosphorylated at Serine 5.

scholarly journals Label-Free Imaging of Single Proteins Secreted from Living Cells via iSCAT Microscopy

10.3791/58486 ◽  
2018 ◽  
Author(s):  
André Gemeinhardt ◽  
Matthew P. McDonald ◽  
Katharina König ◽  
Michael Aigner ◽  
Andreas Mackensen ◽  
...  
Keyword(s):  
Living Cells ◽  
Label Free
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