Search results for "Correlation spectroscopy"
showing 10 items of 39 documents
Monitoring few molecular binding events in scalable confined aqueous compartments by raster image correlation spectroscopy (CADRICS)
2016
The assembly of scalable liquid compartments for binding assays in array formats constitutes a topic of fundamental importance in life sciences. This challenge can be addressed by mimicking the structure of cellular compartments with biological native conditions. Here, inkjet printing is employed to develop up to hundreds of picoliter aqueous droplet arrays stabilized by oil-confinement with mild surfactants (Tween-20). The aqueous environments constitute specialized compartments in which biomolecules may exploit their function and a wide range of molecular interactions can be quantitatively investigated. Raster Image Correlation Spectroscopy (RICS) is employed to monitor in each compartmen…
FRET-based dynamic structural biology: Challenges, perspectives and an appeal for open-science practices.
2021
International audience; Single-molecule FRET (smFRET) has become a mainstream technique for studying biomolecular structural dynamics. The rapid and wide adoption of smFRET experiments by an ever- increasing number of groups has generated significant progress in sample preparation, measurement procedures, data analysis, algorithms and documentation. Several labs that employ smFRET approaches have joined forces to inform the smFRET community about streamlining how to perform experiments and analyze results for obtaining quantitative information on biomolecular structure and dynamics. The recent efforts include blind tests to assess the accuracy and the precision of smFRET experiments among d…
Modeling of Particle Number Fluctuations in Entire Cells
2012
In a recent study we developed a method to model protein diffusion in cells [1], where special attention was given to generating from image data of the measured cell a realistic digital model cell in which protein dynamics were simulated. The method was shown to be well suited for modeling non-equilibrium situations that arise, e.g., in photobleaching experiments, and to be capable of producing more detailed information about protein motion than traditional modeling.Another experimental way to assess protein dynamics is to study fluctuations in the local protein number, as it is done, e.g., in fluorescence correlation spectroscopy (FCS), or in similar measurements that apply single-plane il…
Structural analysis of Cu(II) ligation to the 5'-GMP nucleotide by pulse EPR spectroscopy.
2007
JBIC Journal of Biological Inorganic Chemistry, 12 (6)
Modifying the body distribution of HPMA-based copolymers by molecular weight and aggregate formation.
2011
There is a recognized need to create well-defined polymer probes for in vivo and clinical positron emission tomography (PET) imaging to guide the development of new generation polymer therapeutics. Using the RAFT polymerization technique in combination with the reactive ester approach, here we have synthesized well-defined and narrowly distributed N-(2-hydroxypropyl)methacrylamide homopolymers (pHPMA) (P1* and P2*) and random HPMA copolymers consisting of hydrophilic HPMA and hydrophobic lauryl methacrylate comonomers (P3* and P4*). The polymers had molecular weights below (P1* and P3*) and above the renal threshold (P2* and P4*). Whereas the homopolymers dissolve in isotonic solution as in…
<title>Time-resolved fluorescence study of interaction of the monoclonal anticoproporphyrin antibodies and (Pt-)coproporphyrin</title>
1995
Mechanisms of ligand binding by monoclonal anti-coproporphyrin antibodies are studied by steady-state and time-resolved fluorescence spectroscopy by use of a picosecond laser system. The antibodies quench the coproporphyrin (CP) fluorescence, but the CP fluorescence spectra show a strong shift of maxima at high concentrations of antibodies (Ab) or their Fab fragment. This can be explained by a special type of Ab or Fab dimerization. Fluorescence decays of CP are measured at different concentrations of Ab and different pH values. The following deconvolution procedure based on the non-linear least squares method reveals a two- exponential character of the fluorescence decay. Data obtained by …
Dye-Labeled Poly(organosiloxane) Microgels with Core−Shell Architecture
1999
Poly(organosiloxane) microgels are highly cross-linked rather monodisperse spherical particles of radius about 10 nm. Using a functionalized silane comonomer, i.e., (chlorobenzyl)trimethoxysilane, model particles suitable for studies in colloid physics are available: photoreactive and fluorescent dyes can be covalently bound within the microgels to prepare tracers for diffusion studies using forced Rayleigh scattering (FRS) and fluorescence correlation spectroscopy (FCS). For the application as tracer particles, it is important not to influence the diffusion behavior by the coupled chromophores. Therefore, functionalized precursors with a core−shell architecture are used to minimize labeli…
Fluorescence Decay Time of Single Semiconductor Nanocrystals
2002
We present fluorescence decay measurements of single ZnS covered CdSe nanocrystals. It is shown that the fluorescence decay time is fluctuating during the investigation leading to a multiexponential decay even for a single nanocrystal. In combination with measurements of the fluorescence blinking behavior we find that a high fluorescence intensity is correlated with a long fluorescence decay time. This is consistent with a model of fluctuating nonradiative decay channels leading to variable dynamic quenching processes of the excited state.
Protein diffusion in mammalian cell cytoplasm.
2011
We introduce a new method for mesoscopic modeling of protein diffusion in an entire cell. This method is based on the construction of a three-dimensional digital model cell from confocal microscopy data. The model cell is segmented into the cytoplasm, nucleus, plasma membrane, and nuclear envelope, in which environment protein motion is modeled by fully numerical mesoscopic methods. Finer cellular structures that cannot be resolved with the imaging technique, which significantly affect protein motion, are accounted for in this method by assigning an effective, position-dependent porosity to the cell. This porosity can also be determined by confocal microscopy using the equilibrium distribut…
Disassembly of structurally modified viral nanoparticles: characterization by fluorescence correlation spectroscopy.
2005
Abstract Analysis of the breakdown products of engineered viral particles can give useful information on the particle structure. We used various methods to breakdown both a recombinant enveloped virus and virus-like particles (VLPs) from two non-enveloped viruses and analysed the resulting subunits by fluorescence correlation spectroscopy (FCS). Analysis of the enveloped baculovirus, Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV), displaying the green fluorescent protein (GFP) fused to its envelope protein gp64 was performed in the presence and absence of 5 mM SDS and 25 mM DTT. Without treatment, the viral particle showed a diffusion time of 3.3 ms. In the presence of SDS…