Tempo-Spatially Resolved Scattering Correlation Spectroscopy under Dark-Field Illumination and Its Application to Investigate Dynamic Behaviors of Gold Nanoparticles in Live Cells

2014 ◽  
Vol 136 (7) ◽  
pp. 2775-2785 ◽  
Author(s):  
Heng Liu ◽  
Chaoqing Dong ◽  
Jicun Ren
Keyword(s):  
Gold Nanoparticles ◽  
Dark Field ◽  
Correlation Spectroscopy ◽  
Live Cells ◽  
Dynamic Behaviors ◽  
Spatially Resolved ◽  
Dark Field Illumination

scholarly journals Photothermal raster image correlation spectroscopy of gold nanoparticles in solution and on live cells

2015 ◽  
Vol 2 (6) ◽  
pp. 140454 ◽  
Author(s):  
D. J. Nieves ◽  
Y. Li ◽  
D. G. Fernig ◽  
R. Lévy
Keyword(s):  
Gold Nanoparticles ◽  
Single Molecule ◽  
Correlation Spectroscopy ◽  
Image Correlation ◽  
Live Cells ◽  
Glycerol Water ◽  
Raster Image ◽  
Diffusion Speed ◽  
Image Correlation Spectroscopy ◽  
Representative Area

Raster image correlation spectroscopy (RICS) measures the diffusion of fluorescently labelled molecules from stacks of confocal microscopy images by analysing correlations within the image. RICS enables the observation of a greater and, thus, more representative area of a biological system as compared to other single molecule approaches. Photothermal microscopy of gold nanoparticles allows long-term imaging of the same labelled molecules without photobleaching. Here, we implement RICS analysis on a photothermal microscope. The imaging of single gold nanoparticles at pixel dwell times short enough for RICS (60 μs) with a piezo-driven photothermal heterodyne microscope is demonstrated (photothermal raster image correlation spectroscopy, PhRICS). As a proof of principle, PhRICS is used to measure the diffusion coefficient of gold nanoparticles in glycerol : water solutions. The diffusion coefficients of the nanoparticles measured by PhRICS are consistent with their size, determined by transmission electron microscopy. PhRICS was then used to probe the diffusion speed of gold nanoparticle-labelled fibroblast growth factor 2 (FGF2) bound to heparan sulfate in the pericellular matrix of live fibroblast cells. The data are consistent with previous single nanoparticle tracking studies of the diffusion of FGF2 on these cells. Importantly, the data reveal faster FGF2 movement, previously inaccessible by photothermal tracking, and suggest that inhomogeneity in the distribution of bound FGF2 is dynamic.

scholarly journals Dark-field microscopy enhance visibility of CD31 endothelial staining

2020 ◽  
Vol 64 (3) ◽  
Author(s):  
Eva Jennische ◽  
Stefan Lange ◽  
Ragnar Hultborn
Keyword(s):  
Phase Contrast ◽  
Scattered Light ◽  
Dark Field ◽  
Light Scatter ◽  
Endothelial Lining ◽  
Microscopy Technique ◽  
Dark Field Microscopy ◽  
Dark Field Illumination ◽  
Normal Human ◽  
Intense Light

A simple dark field microscopy technique was used for visualization of blood vessels in normal human renal tissues and carcinoma. Phase contrast condenser ring apt for high power objectives was combined with a 10x objective in order to create a dark field illumination of the specimens examined. The endothelial lining of the vessels had been stained by using CD31 monoclonal antibodies combined with conventional peroxidase immunohistochemistry. The final DAB addition used for this technique induced an intense light scatter in the dark field microscope. This scattered light originating from the endothelial lining made the walls of the bright vessels easily detectable from the dark background.

Manipulation of Nanoparticles Using Dark-Field-Illumination Optical Tweezers with Compensating Spherical Aberration

2009 ◽  
Vol 26 (6) ◽  
pp. 068701 ◽  
Author(s):  
Zhou Jin-Hua ◽  
Tao Run-Zhe ◽  
Hu Zhi-Bin ◽  
Zhong Min-Cheng ◽  
Wang Zi-Qiang ◽  
...  
Keyword(s):  
Optical Tweezers ◽  
Spherical Aberration ◽  
Dark Field ◽  
Dark Field Illumination

scholarly journals Fluorescence Correlation and Cross-Correlation Spectroscopy Unveil Cytoplasmic mRNP Composition and Dynamics

2020 ◽  
Author(s):  
Àngels Mateu-Regué ◽  
Jan Christiansen ◽  
Christian Hellriegel ◽  
Finn Cilius Nielsen
Keyword(s):  
Life Cycle ◽  
Dynamic Analysis ◽  
Cross Correlation ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Correlation Spectroscopy ◽  
Live Cells ◽  
Macromolecular Complexes ◽  
Fluorescence Correlation ◽  
Macromolecular Composition

ABSTRACTUnderstanding the mRNA life cycle requires analysis of the dynamic macromolecular composition and stoichiometry of mRNPs. Fluorescence correlation and cross-correlation spectroscopy (FCS and FCCS) are appealing technologies to study mRNP complexes because they readily provide information about the molecular composition, stoichiometry, heterogeneity and dynamics of the particles. We developed FCS protocols for analysis of live cells and cellular lysates, and demonstrate the feasibility of analysing common cytoplasmic mRNPs composed of core factor YBX1, IMPs (or IGF2BPs) and their interactions with other RNA binding proteins such as PABPC1, ELAVL2 (HuB), STAU1 and FMRP. FCCS corroborated previously reported RNA dependent interactions between the factors and provided an estimate of the relative overlap between the factors in the mRNPs. In this way FCS and FCCS provide a new and useful approach for the quantitative and dynamic analysis of mRNP macromolecular complexes that may complement current biochemical approaches.

scholarly journals Trastuzumab-Modified Gold Nanoparticles Labeled with 211At as a Prospective Tool for Local Treatment of HER2-Positive Breast Cancer

Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 632 ◽  
Author(s):  
Łucja Dziawer ◽  
Agnieszka Majkowska-Pilip ◽  
Damian Gaweł ◽  
Marlena Godlewska ◽  
Marek Pruszyński ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Gold Nanoparticles ◽  
Local Treatment ◽  
Growth Factor Receptor ◽  
Dark Field ◽  
Her2 Positive ◽  
Her2 Positive Breast Cancer ◽  
Biological Studies ◽  
Positive Breast Cancer

Highly localized radiotherapy with radionuclides is a commonly used treatment modality for patients with unresectable solid tumors. Herein, we propose a novel α-nanobrachytherapy approach for selective therapy of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. This uses local intratumoral injection of 5-nm-diameter gold nanoparticles (AuNPs) labeled with an α-emitter (211At), modified with polyethylene glycol (PEG) chains and attached to HER2-specific monoclonal antibody (trastuzumab). The size, shape, morphology, and zeta potential of the 5 nm synthesized AuNPs were characterized by TEM (Transmission Electron Microscopy) and DLS (Dynamic Light Scattering) techniques. The gold nanoparticle surface was modified by PEG and subsequently used for antibody immobilization. Utilizing the high affinity of gold for heavy halogens, the bioconjugate was labelled with 211At obtained by α irradiation of the bismuth target. The labeling yield of 211At was greater than 99%. 211At bioconjugates were stable in human serum. Additionally, in vitro biological studies indicated that 211At-AuNP-PEG-trastuzumab exhibited higher affinity and cytotoxicity towards the HER2-overexpressing human ovarian SKOV-3 cell line than unmodified nanoparticles. Confocal and dark field microscopy studies revealed that 211At-AuNP-PEG-trastuzumab was effectively internalized and deposited near the nucleus. These findings show promising potential for the 211At-AuNP-PEG-trastuzumab radiobioconjugate as a perspective therapeutic agent in the treatment of unresectable solid cancers expressing HER2 receptors.

Effect of Plasmonic Gold Nanoparticles on Benign and Malignant Cellular Autofluorescence: A Novel Probe for Fluorescence Based Detection of Cancer

2007 ◽  
Vol 6 (5) ◽  
pp. 403-412 ◽  
Author(s):  
Ivan El-Sayed ◽  
Xiaohua Huang ◽  
Fima Macheret ◽  
Joseph Oren Humstoe ◽  
Randall Kramer ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Metallic Nanoparticles ◽  
Noble Metal Nanoparticles ◽  
Live Cells ◽  
Epithelial Cell Line ◽  
Optical Probes ◽  
Oral Squamous Carcinoma ◽  
Absorption Of Light

Due to the strong surface fields of noble metal nanoparticles, absorption and scattering of electromagnetic radiation is greatly enhanced. Noble metallic nanoparticles represent potential novel optical probes for simultaneous molecular imaging and photothermal cancer therapy using the enhanced scattering and absorption of light. Further, gold nanoparticles can affect molecular fluorescence via chemical, electronic, or photonic interactions. Live cells generate fluorescence due to intracellular and extracellular molecules. Differences in the biochemical composition between healthy and malignant cells can be exploited in vivo to help identify cancer spectroscopically. The interaction of gold nanoparticles with cellular autofluorescence has not yet been characterized. We hypothesized that gold nanoparticles delivered to live cells in vitro would alter cellular autofluorescence and may be useful as a novel class of contrast agent for fluorescence based detection of cancer. The fluorescence of two fluorophores that are responsible for tissue autofluorescence, NADH and collagen, and of two oral squamous carcinoma cell lines and one immortalized benign epithelial cell line were measured in vitro. Gold nanoparticles of different shapes, both spheres and rods, quenched the fluorescence of the soluble NADH and collagen. Reduction of NADH fluorescence was due to oxidation of NADH to NAD+ catalyzed by gold nanoparticles (results we previously published). Reduction of collagen fluorescence appears due to photonic absorption of light. Furthermore, a mean quenching of 12/8% (p<0.00050) of the tissue autofluorescence of cell suspensions was achieved in this model when nanospheres were incubated with the live cells. Gold nanospheres significantly decrease cellular autofluorescence of live cells under physiological conditions when excited at 280nm. This is the first report to our knowledge to suggest the potential of developing targeted gold nanoparticles optical probes as contrast agents for fluorescence based diagnoses of cancer.

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