Fluorescence recovery after photobleaching (FRAP) is a standard method used to study the dynamics of lipids and proteins in artificial and cellular membrane systems. The advent of confocal microscopy two decades ago has made quantitative FRAP easily available to most laboratories. Usually, a single bleaching pattern/area is used and the corresponding recovery time is assumed to directly provide...

Chromatin looseness, which can be analyzed by fluorescence recovery after photobleaching (FRAP) using eGFP-tagged core histone proteins, is an important index of the differentiation potential of blastomere cells and embryonic stem cells. Whether chromatin looseness is a reliable index of the developmental potential of embryos during ontogenesis is not known. As a necessary first step toward ans...

P2X1 receptors for ATP contribute to signalling in a variety of cell types and following stimulation undergo rapid desensitisation (within 1 s), and require approximately 5 min to recover. In HEK293 cells P2X1 receptors C-terminally tagged with enhanced green fluorescent protein (P2X1-eGFP) were predominantly expressed at the cell surface. Following > 90% photo-bleaching of P2X1-eGFP within a 6...

A simple, automated test measuring the ferric reducing ability of plasma, the FRAP assay, is presented as a novel method for assessing "antioxidant power." Ferric to ferrous ion reduction at low pH causes a colored ferrous-tripyridyltriazine complex to form. FRAP values are obtained by comparing the absorbance change at 593 nm in test reaction mixtures with those containing ferrous ions in know...

Fluorescence Recovery after Photobleaching (FRAP) is a technique widely used in cell biology to observe the dynamics of biological systems, including the diffusion of membrane components. More information is needed on the dynamics of photosynthetic membranes in order to help to understand processes such as photosynthetic electron transport, regulation of light-harvesting, and biogenesis and tur...

Binding can now be quantified in live cells, but the accuracy of such measurements remains uncertain. To address this uncertainty, we compare fluorescence recovery after photobleaching (FRAP) and fluorescence correlation spectroscopy (FCS) measurements of the binding kinetics of a transcription factor, the glucocorticoid receptor, in the nuclei of live cells. We find that the binding residence ...

Oxidant/antioxidant imbalance has been reported in some infectious diseases, including community-acquired pneumonia (CAP). The aim was to assess the antioxidant status in adults with CAP and its relationship with clinical severity at admission. Fifty-nine patients with CAP were enrolled and categorized at admission by the FINE score, from July 2010 to October 2012. In the same period 61 control...

Three assays were compared for the determination of total antioxidant capacity in human serum: the oxygen radical absorbance capacity (ORAC) assay, the Randox Trolox-equivalent antioxidant capacity (Randox-TEAC) assay, and the ferric reducing ability (FRAP) assay. There was a weak but significant linear correlation between serum ORAC and serum FRAP. There was no correlation either between serum...