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Chemoluminescence (sometimes "chemiluminescence") is the emission of light (luminescence) as the result of a chemical reaction. Most simply, given reactants A and B, with an excited intermediate ◊, we have, Three types of lightsticks in five colours File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
Three types of lightsticks in five colours File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
Three types of lightsticks in five colours A lightstick, also called a glowstick, is a transparent plastic tube which contains chemical fluids held apart in two compartments. ...
Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of wavelengths that are studied in the field of optics. ...
Luminescence is light not generated by high temperatures alone. ...
In chemistry, the reactants are the substances that exist at the start of a chemical reaction. ...
In chemistry a reactive intermediate is a short-lived high energy highly reactive molecule. ...
[A] + [B] → [◊] → [Products] + light Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of wavelengths that are studied in the field of optics. ...
The decay of the excited state[◊] to a lower energy level is responsible for the emission of light. In theory, one photon of light should be given off for each molecule of reactant, or Avogadro's number of photons per mole. In actual practice, non-enzymatic reactions seldom exceed 1% QC, quantum efficiency. A graph showing variation of quantum efficiency with wavelength of the CCD chips in the Hubble Space Telescopes Wide Field and Planetary Camera 2. ...
For example, if [A] is luminol and [B] is hydrogen peroxide in the presence of a suitable catalyst we have,
luminol + H2O2 → 3-APA[◊] → 3-APA + light
Where 3-APA is 3-aminophthalate. And 3-APA[◊] is the excited state florescing as it decays to a lower energy level.
A standard example of chemoluminescence in the laboratory setting is found in the luminol test, where evidence of blood is taken when the sample glows upon contact with iron. Synthesis of Luminol. ...
Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ...
Luminescence is light not generated by high temperatures alone. ...
General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ...
When chemoluminescence takes place in living organisms, the phenomenon is called bioluminescence. Bioluminescence is the production and emission of light by a living organism as the result of a chemical reaction during which chemical energy is converted to light energy. ...
A lightstick emits light by chemoluminescence. Three types of lightsticks in five colours A lightstick, also called a glowstick, is a transparent plastic tube which contains chemical fluids held apart in two compartments. ...
Liquid-phase reactions
Luminol in an alkaline solution with hydrogen peroxide in the presence of iron or copper[1], or an auxiliary oxidant[2], produces chemoluminescence. The luminol reaction is image from Penn state haloween chemistry show [1] This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ...
image from Penn state haloween chemistry show [1] This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ...
Synthesis of Luminol. ...
Flash point Non-flammable. ...
luminol + H2O2 → 3-APA[◊] → 3-APA + light
The quantum efficiency, QC is 1%. For the laboratory experiment see references [1],[2].
Cyalume, as used in a lightstick, emits light by chemoluminescence of a fluorescent dye activated by cyalume reacting with hydrogen peroxide in the most efficient non-enzymatic reaction known.[3] Three types of lightsticks in five colours A lightstick, also called a glowstick, is a transparent plastic tube which contains chemical fluids held apart in two compartments. ...
Flash point Non-flammable. ...
cyalume + H2O2 + dye → phenol + 2CO2 + dye[◊]
When the activated fluorescent dye decays to a lower energy level, light is given off. The color depends upon the dye. For a list of dyes see reference [4].
There are a number of other chemiluminescence reactions. Some of them are briefly described here.
Ru(bipy)32+ is a ruthenium(II) complex which undergoes oxidation to ruthenium(III) if certain oxidizing agents are introduced. If ruthenium(III) complex is then reduced in alkaline medium, emission of light occurs. General Name, Symbol, Number ruthenium, Ru, 44 Chemical series transition metals Group, Period, Block 8, 5, d Appearance silvery white metallic Atomic mass 101. ...
First, there is a reaction:
2Ru(bipy)32+ + PbO2 + 4H+ → 2Ru(bipy)33+ + Pb2+ + 2H2O
Here, Ru(III) is obtained. Further reaction includes use of solution of sodium tetrahydroborate(III), NaBH4 in alkaline medium. When the solution is added, Ru(III) is reduced to Ru(II) and we get orange light.
TMAE (chemically tetrakis(dimethylamino) ethylene) can be oxidized by air. When that happens, emission of clear blue green light occurs.
Oxalyl chloride (C2O2Cl2) produces light when oxidized - but only in the presence of a sensitiser. That can be any compound with rigid system of aromatic rings or a compound, which includes enough double or triple bonds in its structure to store electrochemical energy through means of vibration. The excited molecule (in this case, oxalyl chloride) transfers its electrochemical energy in certain phase of chemical reaction to sensitiser, thus making the sensitiser excited and capable of light emission. Good examples are rodamine 6 G, fluorescein, violanthrone and similar compounds. Anyway, if oxalyl chloride is treated with H2O2 in non-aqueous media (e.g. CH2Cl2) in the presence of sensitiser, emission of light is obtained. The colour, intensity and duration of light emission depend on the sensitiser used. Rodamin 6 G gives bright orange light with moderate duration of emission. Sensitiser in chemoluminescence is a compound, capable of light emission after it has received energy from a molecule, which became excited previously in the chemical reaction. ...
This page is a list of sources of light. ...
fluorescein isothiocyanate Fluorescein is a fluorophore commonly used in microscopy, in a type of dye laser as the gain medium, and in forensics and serology to detect latent blood stains. ...
Pyrogallol (chemically 1,2,3-trihydroxibenzene) is also capable of light emission under right circumstances. If an aqueous solution of pyrogallol, NaOH and K2CO3 is mixed with formaldehyde, short-lived red emission occurs. Pyrogallol Pyrogallol or benzene-1,2,3-triol is a white crystalline powder and a powerful reducing agent. ...
The chemical compound formaldehyde (also known as methanal), is a gas with a strong pungent smell. ...
Pure oxygen (O2) can also emit light. If solutions of 30% hydrogen peroxide and 5% alkaline sodium chlorate(I) (NaClO) are mixed, red light is emitted. It is barely visible, though - for this reason, in such experiment sensitiser is often included to boost light emission in terms of brightness and intensity. Again, both colour and intensity of light depend on sensitiser used. Sodium hypochlorite is a chemical compound with the formula NaOCl. ...
Lucigenin oxidation is also very well known among chemiluminescence reactions. If an aqueous lucigenin solution is mixed with highly alkaline aqueous solution containing ethanol or acetone and hydrogen peroxide, very bright green emission is produced that decays to greenish blue and finally blue emission. The duration of the emission can be up to a couple of minutes under the right circumstances. Lucigenin Lucigenine is a aromatic compound, mainly used in areas which include chemoluminescence. ...
Ethanol, also known as ethyl alcohol or grain alcohol, is a flammable, colorless chemical compound, one of the alcohols that is most often found in alcoholic beverages. ...
R-phrases , , , S-phrases , , , Flash point -20 °C Autoignition temperature 465 °C RTECS number AL31500000 Supplementary data page Structure & properties n, εr, etc. ...
Flash point Non-flammable. ...
For more information about how to perform experiments mentioned, see the reference [5].
Gas-phase reactions One of the oldest known chemoluminescent reactions is that of elemental white phosphorus oxidizing in moist air, producing a green glow. This is actually a gas-phase reaction of phosphorus vapor, above the solid, with oxygen producing excited states (PO)2 and HPO.[3] This article is about the chemical element. ...
Another gas phase reaction is the basis of nitric oxide detection in commercial analytic instruments applied to environmental air quality testing. Ozone is combined with nitric oxide to form nitrogen dioxide in an activated state. The chemical compound nitric oxide is a gas with chemical formula NO. It is an important signaling molecule in the body of mammals including humans, one of the few gaseous signaling molecules known. ...
For other uses, see Ozone (disambiguation). ...
NO+O3 → NO2[◊]+ O2
The activated NO2[◊] luminesces broadband visible to infrared light as it reverts to a lower energy state. A photomultiplier and associated electronics counts the photons which are proportional to the amount of NO present. Photomultipliers, or photomultiplier tubes (PMT) are extremely sensitive detectors of light in the ultraviolet, visible and near infrared. ...
To determine the amount of nitrogen dioxide, NO2, in a sample (containing no NO) it must first be converted to nitric oxide, NO, by passing the sample through a converter before the above ozone activation reaction is applied. The ozone reaction produces a photon count proportional to NO which is proportional to NO2 before it was converted to NO. [1] R-phrases , S-phrases , , , , , Supplementary data page Structure and properties n, εr, etc. ...
In the case of a mixed sample containing both NO and NO2, the above reaction yields the amount of NO and NO2 combined in the air sample, assuming that the sample is passed though the converter.
If the mixed sample is not passed through the converter, the ozone reaction produces activated NO2[◊] only in proportion to the NO in the sample. The NO2 in the sample is not activated by the ozone reaction. Though unactivated NO2 is present with the acitvated NO2[◊], photons are only emitted by the activated species which is proportional to original NO.
Final step, subtract NO from (NO + NO2) to yield NO2
Bioluminescence - Main article: Bioluminescence
Chemoluminescence takes place in numerous living organisms, the American firefly being a widely studied case of bioluminescence. Bioluminescence is the production and emission of light by a living organism as the result of a chemical reaction during which chemical energy is converted to light energy. ...
The firefly reaction has the highest known quantum efficiency, QC of 88%, for chemoluminescence reactions. ATP (adenosine tri-phosphate), the ubiquitous biological energy source, reacts with luciferin with the aid of the enzyme luciferase to yield an intermediate complex. This complex combines with oxygen to produce a highly fluorescent compound. A graph showing variation of quantum efficiency with wavelength of the CCD chips in the Hubble Space Telescopes Wide Field and Planetary Camera 2. ...
Adenosine 5-triphosphate (ATP) is a multifunctional nucleotide primarily known in biochemistry as the molecular currency of intracellular energy transfer. ...
Luciferin is a generic name for light-emitting pigments found in organisms capable of bioluminescence, like fireflies, deep-sea fish and microbes. ...
Luciferase is a generic name for enzymes commonly used in nature for bioluminescence. ...
ECL Enzymatic Chemiluminescence (ECL) is a common technique for a variety of detection assays in biology. a horseradish peroxidase molecule (HRP) is tethered to the molecule of interest (usually by immunoglobulin staining). This then locally catalyzes the conversion of the ECL reagent into a sensitized reagent, which on further oxidation by hydrogen peroxide, produces a triplet (excited) carbonyl which emits light when it decays to the singlet carbonyl.
The mechanism of action for a typical ECL reagent:
 Mechanism for ECL File links The following pages link to this file: Chemoluminescence ...
Applications of chemoluminescence - gas analysis: for determining small amounts of impurities or poisons in air. Other compounds can also be determined by this method (ozone, N-oxides, S-compounds). Typical example is NO determination with detection limits down to 1 ppb
- analysis of inorganic species in liquid phase
- analysis of organic species: useful with enzymes, where the substrate isn't directly involved in chemiluminescence reaction, but the product is
For other uses, see Ozone (disambiguation). ...
Ribbon diagram of the enzyme TIM. TIM is catalytically perfect, meaning its conversion rate is limited, or nearly limited to its substrate diffusion rate. ...
See also This page is a list of sources of light. ...
External links and references - ^ a b "Luminol chemistry laboratory demonstration." URL accessed on 2006-03-29.
- ^ a b "Investigating luminol." (PDF) Salters Advanced Chemistry. URL accessed on 2006-03-29.
- ^ a b Rauhut, Michael M. (1985), Chemiluminescence. In Grayson, Martin (Ed) (1985). Kirk-Othmer Concise Encyclopedia of Chemical Technology (3rd ed), pp 247 John Wiley and Sons. ISBN 0-471-51700-3
- ^ Helmenstine, Anne Marie (Aug 10, 2004). Light stick chemistry, retrieved Sept. 22, 2004.
- ^ Bassam Z. Shakhashiri: Chemical Demonstrations, Volume 1, University of Wisconsin 1983.
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