Diffusion is often an important rate-determining step in chemical reactions or biological processes and plays a role in a wide range of intracellular events. Viscosity is one of the key parameters affecting the diffusion of molecules and proteins, and changes in viscosity have been linked to disease and malfunction at the cellular level. While methods to measure the bulk viscosity are well deve...

background: in algeria, the data on infertility and its various causes are rare. recently, the introduction of assisted reproduction has allowed expecting that 300000 couples, which represent 7% of couples of reproductive age, face difficulty conceiving a child. knowing that most idiopathic cases are likely to be due to chromosomal abnormalities, we aimed to investigate genetic defects by karyo...

BACKGROUND X-ray computed tomography (CT) imaging can be used to reveal the three-dimensional structure of deep tissue with high spatial resolution. However, it cannot reveal molecular or cellular changes, and has great limitations in terms of specificity and sensitivity. Fluorescence imaging technology is one of the main methods used for the study of molecular events in vivo and has important ...

Articles you may be interested in Polar solvation dynamics of coumarin 153 by ultrafast time-resolved fluorescence Dynamical theory of time-resolved fluorescence with pulse excitation Molecular dynamics modeling of timeresolved fluorescence shifts in liquid solution The results of time-resolved Stokes shift measurements are compared to a molecular theory of ionic solvation dynamics recently sol...

Molecular nanoribbons are a class of atomically-precise nanomaterials for broad range applications. An iterative approach that allows doubling the length longest pyrene-pyrazinoquinoxaline molecular is described. The largest nanoribbon obtained through this approach—with 60 linearly-fused ring backbone (14.9 nm) and 324-atoms core (C276N48)—shows an extremely high molar absorptivity (values up ...

BACKGROUND Molecular sensing/imaging utilizing fluorophores has been one of the most frequently used techniques in biomedical research. As for any molecular imaging techniques, fluorescence mediated sensing always seeks for greater specificity and sensitivity. Since fluorophores emit fluorescence while their electron energy state changes, manipulating the local electromagnetic field around the ...

We perform time-resolved fluorescence spectroscopy on clusters of plasmonic nanoantennas covered with a dye-polymer mixture. Dimer antenna structures were fabricated consisting of two interacting gold nanorods with varying lengths and interparticle separation. By combining four individual antennas into a cluster within a diffraction limited spot size, we can couple out half of the dye molecule ...

Fluorescence correlation spectroscopy (FCS) is a method based on the correlation analysis of the temporal behaviour of fluorescence intensity fluctuations. It is commonly used to determine diffusion coefficients and concentrations of samples in the (sub)nano-molar concentration regime. Another quantity made accessible by FCS is the mean number of detected fluorescence photons per molecule and t...

In this work, we modify the multisite Stern-Volmer (MSV) equation for fitting fluorescence titration curves. Under the condition of a static quenching mechanism, the MSV postulates an underlying 1:1 fulvic acid (FA)/copper coordination ratio at multisites. Approximates of six fitting parameters characterize the stability constants (K1 and K2) of FA ligands with Cu2+, micromolar ligand site conc...

Molecular packing arrangements play a key role in dominating the photophysical properties of luminophores in aggregated state but fine control of the molecular packing is a great challenge. This article describes a unique cyano substituted styrene pyridinium with interesting solid-state fluorescence that can be finely tuned by simple change of counteranions. The dilute solutions of the organic ...