It is difficult to obtain precise quantitative measurements from fluorescent images captured from widefield microscopes. We wished to ascertain if reliable quantitative measurements of both biological and nonbiological specimens were possible using a widefield microscope equipped with a structured illumination system and image analysis software. In a nonbiological specimen, images were obtained...

Monitoring neuronal electrical activity using fluorescent protein-based voltage sensors has been limited by small response magnitudes and slow kinetics of existing probes. Here we report the development of a fluorescent protein voltage sensor, named ArcLight, and derivative probes that exhibit large changes in fluorescence intensity in response to voltage changes. ArcLight consists of the volta...

PURPOSE In vaccine efficacy evaluation, visualization of pathogens in whole organism at each time point would be able to reduce the consuming animals and provide the in vivo information within consistent background with identical organism. MATERIALS AND METHODS Using IVIS spectrum whole live-animal imaging system, fluorescent intensity was optimized and visualized proportionately by concentra...

A fluorescent probe, DPPEC (1,2-dipalmitoylglycerophosphorylethanolamine labeled with coumarin) was developed for detecting hydroxyl radical (*OH) in lipid membranes. The coumarin moiety contributes to the fluorescent detection of *OH and the phospholipids moiety gives a driving force to localize the probe in lipid membranes. DPPEC in liposomal membranes rapidly reacted with *OH and increased t...

Advances in microarray technologies have made it possible to comprehensively measure gene expression profiles. However, in these experiments, the efficiency of fluorescent dyes are different between different experiments, and adjustments of these expression values are mandatory before the analysis, It is referred to as normalization. Although the most popular method is total intensity normaliza...

An improved method for separation and fluorescent analysis of coproporphyrin and uroporphyrin in urine was presented by Sobel, Cano, and Thiers [Clin. Chem. 20, 1397 (1974)]. Accurate determination of porphyrin concentrations by this method is impeded by the fluorescent background in urine samples, which varies from one specimen to another. By use of a straightforward procedure, zinc may be inc...

Optical imaging is a modality that is cost-effective, rapid, easy to use, and can be readily applied to studying disease processes and biology in vivo. For this study, we used a green fluorescent protein (GFP)- and luciferase-expressing mouse tumor model to compare and contrast the quantitative and qualitative capabilities of a fluorescent reporter gene (GFP) and a bioluminescent reporter gene ...

The fluorescent intensity of Cy3 and Cy5 dyes is strongly dependent on the nucleobase sequence of the labeled oligonucleotides. Sequence-dependent fluorescence may significantly influence the data obtained from many common experimental methods based on fluorescence detection of nucleic acids, such as sequencing, PCR, FRET, and FISH. To quantify sequence dependent fluorescence, we have measured ...

After the discovery of riboflavin, and its identification as vitaminr B,, assay methods based on the measurement of its fluorescence intensity were described (v. Euler & Adler, 1934; Cohen, 1934; Josephy, 1934). Similar methods of assay were developed for vitamin B1 after Jansen (1936) had shown that thiochrome, the fluorescent oxidation product of thiamin, could be used as the basis for the fl...