Questions tagged [fluorescence]
For questions relating to the radiation emitted by substances as a result of incident radiation.
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How the optical fibre pH microsensors work?
Just browsed through the chemical sensor products of the company, called PreSens (https://www.presens.de/products/ph/sensors) in order to look for a precise method to measure pH change in a ...
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Spectroscopic methods for quantifying peptides/proteins with or without Tryptophan or Tyrosine content
I have several peptides (20-50 amino acids long) which I want to quantify the solubility/concentration in a solvent at certain temperature and pH.
These peptides may or may not contain Tryptophan or ...
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DNA staining agent with good absorbance at 532 nm
I need to stain some double-stranded DNA with an intercalating fluorescent dye. For imaging, I am using a microscope setup equiped with a 532 nm green laser.
What is the staining agent of choice to ...
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Fluorophores with high quantum yield and low lifetime
Does anyone know of any fluorophore or family of fluorophores with a relatively high fluorescence quantum yield (larger than 0.1) and a short lifetime (below hundreds of picoseconds)?
I have been ...
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How does molecular structure contribute in the property of fluorescence?
Fluorescence is the property which is exhibited when electrons emit wavelength of light lower than the one they absorbed so does that mean we can make every molecule to become fluorescent? I wanted to ...
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Dark smudge at the TLC solvent front
I have recently started using TLC in my graduate work to test for the cleavage of a cyclic oligo-adenylate in an enzymatic reaction. The sample I'm spotting on my plate is in an aqueous solution ...
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Wave Dispersive X-ray Fluoresence and Bragg's Law
Thermo Fisher website explains that "WDXRF uses crystals to disperse the fluorescence spectrum into individual wavelengths of each element, providing high resolution and low background spectra ...
user119534
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Why does isolated chlorophyl emits red light?
If we observe isolated chlorophyl solution with UV light, chlorophyl is seen as red. Explanation suggests that when a specific atom of chlorophyl absorbs UV light, the atom gets excited and in a short ...
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Fluorescence: what mechanism regulates the rate of discharge of energy?
The other day, I noticed a strip of fluorescent tape when the lights in the room were turned off.
The energy was discharged as a continued, faint glow, rather than one burst or flash of light.
How so? ...
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Why wouldn't a standard addition fluorometric method return the same starting concentration of a solution used to make the standards?
I am trying out a new standard addition method and having some very basic problems. I am hoping someone could point me in the right direction.
I am using a fluorometric method to quantify ammonium in ...
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What causes horizontal lines on an excitation-emission matrix in fluorometry?
I am doing excitation-emission matrices to test for CDOM, and we just got some brand new quarts cuvettes. When I hold them in front of a light, they're totally clear and clean.
I ran a sample, and in ...
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Fluorochrome (fluorescein) emission decay when linked to macromolecule
I measure the intensity and polarization of light emitted from a blood sample that contains excited fluorescein (experiment known as fluorescence polarization assay). The excitation is done, as usual, ...
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How can I save an EEM file on a Fluoromax4?
I'm trying to run excitation-emission matrices on some water samples, but I'm running into some software issues that the manuals aren't helpful for. In order to use R studio to extract my data, I need ...
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How can I set up and process my excitation-emission matrices properly?
I'm running EEMS on some water samples on a Horiba Fluoromax 4 spectrofluorometer. Method below.
$\pu{240-580nm}$ emission, $\pu{5nm}$ interval, $\pu{1nm}$ width.
$\pu{240-480nm}$ excitation, $\pu{...
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What is the amount of UV light required to make fluorophores glow and what is the minimum amount of electricity needed to achieve this?
So I have heard that fluorophores glow under UV light, so I was wondering what is the minimum amount of UV light needed to make the fluorophores glow and what would be the minimum amount of ...
