Fluorescent minerals

Fluorescence is a luminescence that is mostly found as an optical phenomenon in cold bodies, in which the molecular absorption of a photon triggers the emission of another photon with a longer wavelength. Luminescence is also the title of an album by singer Anggun. Luminescence is Light not generated by high temperatures alone An optical phenomenon is any observable event which results from the interaction of Light and Matter. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. The energy difference between the absorbed and emitted photons ends up as molecular vibrations or heat. The kinetic energy of an object is the extra Energy which it possesses due to its motion In Physics, heat, symbolized by Q, is Energy transferred from one body or system to another due to a difference in Temperature Usually the absorbed photon is in the ultraviolet range, and the emitted light is in the visible range, but this depends on the absorbance curve and Stokes shift of the particular fluorophore. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 Stokes shift is the difference (in Wavelength or Frequency units between positions of the band maxima of the absorption and emission A fluorophore, in analogy to a Chromophore, is a component of a molecule which causes a molecule to be Fluorescent. Fluorescence is named after the mineral fluorite, composed of calcium fluoride, which often exhibits this phenomenon. A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific Fluorite (also called fluorspar) is a Mineral composed of Calcium fluoride, Ca[[Fluorine F2]] Calcium fluoride (CaF2 is an insoluble Ionic compound of Calcium and Fluorine.

Equations

Photochemistry

Fluorescence occurs when a molecule , atom or nanostructure relaxes to its ground state after being electrically excited. A nanostructure is an object of intermediate size between Molecular and Microscopic ( micrometer -sized Structures In describing nanostructures In Quantum mechanics, a stationary state is an Eigenstate of a Hamiltonian, or in other words a state of definite energy

Excitation:

Fluorescence (emission): , here hν is a generic term for photon energy where: h = Planck's constant and ν = frequency of light. The Planck constant (denoted h\ is a Physical constant used to describe the sizes of quanta. Frequency is a measure of the number of occurrences of a repeating event per unit Time. (The specific frequencies of exciting and emitted light are dependent on the particular system. )

State S₀ is called the ground state of the fluorophore (fluorescent molecule) and S₁ is its first (electronically) excited state. A fluorophore, in analogy to a Chromophore, is a component of a molecule which causes a molecule to be Fluorescent.

A molecule in its excited state, S₁, can relax by various competing pathways. It can undergo 'non-radiative relaxation' in which the excitation energy is dissipated as heat (vibrations) to the solvent. Excited organic molecules can also relax via conversion to a triplet state which may subsequently relax via phosphorescence or by a secondary non-radiative relaxation step. In Physics, '''spin''' is the Angular momentum intrinsic to a body as opposed to Orbital angular momentum, which is the motion of its Center of mass Phosphorescence is a specific type of Photoluminescence related to fluorescence.

Relaxation of an S₁ state can also occur through interaction with a second molecule through fluorescence quenching. Quenching refers to any process which decreases the Fluorescence intensity of a given substance Molecular oxygen (O₂) is an extremely efficient quencher of fluorescence because of its unusual triplet ground state. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the

Molecules that are excited through light absorption or via a different process (e. g. as the product of a reaction) can transfer energy to a second 'sensitized' molecule, which is converted to its excited state and can then fluoresce. This process is used in lightsticks. A glow stick is a single-use translucent Plastic tube containing isolated substances which when combined are capable of producing Light through a Chemical reaction

Quantum yield

The fluorescence quantum yield gives the efficiency of the fluorescence process. The quantum yield of a Radiation -induced process is the number of times that a defined event occurs per Photon absorbed by the system It is defined as the ratio of the number of photons emitted to the number of photons absorbed.

The maximum fluorescence quantum yield is 1. 0 (100%); every photon absorbed results in a photon emitted. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena Compounds with quantum yields of 0. 10 are still considered quite fluorescent. Another way to define the quantum yield of fluorescence, is by the rates excited state decay:

where k_f is the rate of spontaneous emission of radiation and

∑	ki
i

is the sum of all rates of excited state decay. Spontaneous emission is the process by which a light source such as an Atom, Molecule, Nanocrystal or nucleus in an Excited state Other rates of excited state decay are caused by mechanisms other than photon emission and are therefore often called "non-radiative rates", which can include: dynamic collisional quenching, near-field dipole-dipole interaction (or resonance energy transfer), internal conversion and intersystem crossing. Förster resonance energy transfer (abbreviated FRET) also known as Fluoresence resonance energy transfer or resonance energy transfer ( RET Intersystem crossing is a photophysical process An isoenergetic non-radiative transition between two Electronic states having different multiplicities. Thus, if the rate of any pathway changes, this will affect both the excited state lifetime and the fluorescence quantum yield.

Fluorescence quantum yield are measured by comparison to a standard with known quantology; the quinine salt, quinine sulfate, in a sulfuric acid solution is a common fluorescence standard. Quinine (ˈkwaɪnaɪn kwɪˈniːn ˈkwiːniːn is a natural white Crystalline Alkaloid having Antipyretic (fever-reducing antimalarial,

Lifetime

The fluorescence lifetime refers to the average time the molecule stays in its excited state before emitting a photon. Fluorescence typically follows first-order kinetics:

where is the concentration of excited state molecules at time t, is the initial concentration and Γ is the decay rate or the inverse of the fluorescence lifetime. This is an instance of exponential decay. A quantity is said to be subject to exponential decay if it decreases at a rate proportional to its value Various radiative and non-radiative processes can de-populate the excited state. In such case the total decay rate is the sum over all rates:

Γ_tot = Γ_rad + Γ_nrad

where Γ_tot is the total decay rate, Γ_rad the radiative decay rate and Γ_nrad the non-radiative decay rate. It is similar to a first-order chemical reaction in which the first-order rate constant is the sum of all of the rates (a parallel kinetic model). If the rate of spontaneous emission, or any of the other rates are fast, the lifetime is short. For commonly used fluorescent compounds typical excited state decay times for fluorescent compounds that emit photons with energies from the UV to near infrared are within the range of 0. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of 5 to 20 nanoseconds. The second ( SI symbol s) sometimes abbreviated sec, is the name of a unit of Time, and is the International System of Units The fluorescence lifetime is an important parameter for practical applications of fluorescence such as fluorescence resonance energy transfer. Förster resonance energy transfer (abbreviated FRET) also known as Fluoresence resonance energy transfer or resonance energy transfer ( RET

Rules

There are several rules that deal with fluorescence. A rule of thumb is a principle with broad application that is not intended to be strictly accurate or reliable for every situation The Kasha – Vavilov rule dictates that the quantum yield of luminescence is independent of the wavelength of exciting radiation.

This is not always true and is violated severely in many simple molecules. A somewhat more reliable statement, although still with exceptions, would be that the fluorescence spectrum shows very little dependence on the wavelength of exciting radiation.

The Jablonski diagram describes most of the relaxation mechanism for excited state molecules. Jablonski diagram, named after the Polish physicist Aleksander Jabłoński, is a diagram that illustrates the Electronic states of a Molecule and the transitions

Applications

There are many natural and synthetic compounds that exhibit fluorescence, and they have a number of applications. Some deep-sea animals, such as the Greeneye, use fluorescence. Greeneyes are deep-sea Aulopiform marine Fishes in the small family Chlorophthalmidae.

Lighting

The common fluorescent tube relies on fluorescence. A fluorescent lamp or fluorescent tube is a Gas-discharge lamp that uses Electricity to excite mercury Vapor. Inside the glass tube is a partial vacuum and a small amount of mercury. Glass in the common sense refers to a Hard, Brittle, transparent Solid, such as that used for Windows many Mercury (ˈmɜrkjʊri also called quicksilver or hydrargyrum, is a Chemical element with the symbol Hg ( Latinized hydrargyrum An electric discharge in the tube causes the mercury atoms to emit light. The emitted light is in the ultraviolet (UV) range, is invisible, and is harmful to most living organisms. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays The tube is lined with a coating of a fluorescent material, called the phosphor, which absorbs the ultraviolet and re-emits visible light. A phosphor is a substance that exhibits the phenomenon of Phosphorescence (sustained glowing after exposure to energized particles such as Electrons Fluorescent lighting is very energy efficient compared to incandescent technology, but the spectra produced may cause certain colours to appear unnatural. Lighting includes both artificial Light sources such as lamps and natural illumination of interiors from Daylight. Incandescence is the emission of Light (visible Electromagnetic radiation) from a hot body due to its temperature

In the mid 1990s, white light-emitting diodes (LEDs) became available, which work through a similar process. Typically, the actual light-emitting semiconductor produces light in the blue part of the spectrum, which strikes a phosphor compound deposited on the chip; the phosphor fluoresces from the green to red part of the spectrum. A semiconductor' is a Solid material that has Electrical conductivity in between a conductor and an insulator; it can vary over that The combination of the blue light that goes through the phosphor and the light emitted by the phosphor produce a net emission of white light.

The modern mercury vapor streetlight is said to have been evolved from the fluorescent lamp. A street light, lamppost, street lamp, light standard or lamp standard, is a raised source of Light on the edge of a Road

Glow sticks oxidise phenyl oxalate ester in order to produce light. A glow stick is a single-use translucent Plastic tube containing isolated substances which when combined are capable of producing Light through a Chemical reaction Diphenyl oxalate (trademark name Cyalume) is a solid Ester whose Oxidation products are responsible for the Chemiluminescence in a

Compact fluorescent lighting (CFL) is the same as any typical fluorescent lamp with advantages. It is self-ballasted and used to replace incandescents in most applications. They produce a quarter of the heat per lumen as incandescent bulbs and last about five times as long. Incandescence is the emission of Light (visible Electromagnetic radiation) from a hot body due to its temperature These bulbs contain mercury and must be handled and disposed with care. The disadvantages to the self-ballasting properties of compact fluorescent is that they may not fit properly in all light fixtures. All fluorescent lights have a significant delay in turning on compared to incandescents, a disadvantage in some applications. Additionally, the technology which allows them to be 'plug-and-play' also significantly reduces their life-span and reliability in dimming applications.

Analytical chemistry

Fluorescence in several wavelengths can be detected by an array detector, to detect compounds from HPLC flow. High-performance liquid chromatography (or High pressure liquid chromatography, HPLC) is a form of Column chromatography used frequently in Biochemistry Also, TLC plates can be visualized if the compounds or a coloring reagent is fluorescent. Thin layer chromatography (TLC is a Chromatography technique used to separate mixtures Fluorescence is most effective when there is a larger ratio of atoms at lower levels in a Boltzmann distribution because then there is more of a chance those atoms will be excited then release a photon and can be analyzed. WikipediaWikiProject Probability#Standards for a discussion of standards used for probability distribution articles such as this one

Fingerprints can be visualized with fluorescent compounds such as ninhydrin. A fingerprint is an impression of the friction ridges of all or any part of the finger Ninhydrin (triketohydrindene hydrate is a chemical used to detect Ammonia or primary and secondary Amines When reacting with these free amines a deep blue or

Biochemistry and medicine

Biological molecules can be tagged with a fluorescent chemical group (fluorophore) by a simple chemical reaction, and the fluorescence of the tag enables sensitive and quantitative detection of the molecule. A fluorophore, in analogy to a Chromophore, is a component of a molecule which causes a molecule to be Fluorescent. Examples:

• Fluorescence microscopy of tissues, cells or subcellular structures is accomplished by labeling an antibody with a fluorophore and allowing the antibody to find its target antigen within the sample. A fluorescence microscope (colloquially synonymous with epifluorescent microscope) is a light Microscope used to study properties of organic or inorganic substances Labeling multiple antibodies with different fluorophores allows visualization of multiple targets within a single image.
• Automated sequencing of DNA by the chain termination method; each of four different chain terminating bases has its own specific fluorescent tag. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known The term DNA sequencing encompasses biochemical methods for determining the order of the Nucleotide bases Adenine, Guanine, Cytosine As the labeled DNA molecules are separated, the fluorescent label is excited by a UV source, and the identity of the base terminating the molecule is identified by the wavelength of the emitted light.

Ethidium bromide stained agarose gel. Agarose Gel electrophoresis is a method used in Biochemistry and Molecular biology to separate DNA, or RNA molecules by size Ethidium bromide fluoresces orange when intercalating DNA and when exposed to UV light. In Chemistry, intercalation is the reversible inclusion of a Molecule (or group between two other molecules (or groups Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays

• DNA detection: the compound ethidium bromide, when free to change its conformation in solution, has very little fluorescence. Ethidium bromide (sometimes abbreviated as "EtBr", the abbreviation also confusingly used for Bromoethane) is an intercalating agent Ethidium bromide's fluorescence is greatly enhanced when it binds to DNA, so this compound is very useful in visualising the location of DNA fragments in agarose gel electrophoresis. Agarose Gel electrophoresis is a method used in Biochemistry and Molecular biology to separate DNA, or RNA molecules by size Ethidium bromide can be toxic - a safer alternative is the dye SYBR Green. SYBR Green I ( SG) is an asymmetrical Cyanine dye used as a Nucleic acid Stain in Molecular biology.
• The DNA microarray
• Immunology: An antibody has a fluorescent chemical group attached, and the sites (e. For terminology see glossary below A DNA microarray is a High-throughput technology used in Molecular biology and in g. , on a microscopic specimen) where the antibody has bound can be seen, and even quantified, by the fluorescence.
• FACS (fluorescent-activated cell sorting)
• Fluorescence has been used to study the structure and conformations of DNA and proteins with techniques such as Fluorescence resonance energy transfer, which measures distance at the angstrom level. Flow cytometry is a technique for counting examining and sorting microscopic particles suspended in a stream of fluid Förster resonance energy transfer (abbreviated FRET) also known as Fluoresence resonance energy transfer or resonance energy transfer ( RET This is especially important in complexes of multiple biomolecules.
• Aequorin, from the jellyfish Aequorea victoria, produces a blue glow in the presence of Ca²⁺ ions (by a chemical reaction). Aequorin is a photoprotein isolated from Luminescent Jellyfish (like various Aequorea species e Aequorea victoria, also called the crystal jelly, is a Bioluminescent Jellyfish that is found off the west coast of North America It has been used to image calcium flow in cells in real time. The success with aequorin spurred further investigation of A. victoria and led to the discovery of Green Fluorescent Protein (GFP), which has become an extremely important research tool. The green fluorescent protein ( GFP) is composed of 238 Amino acids (26 GFP and related proteins are used as reporters for any number of biological events including such things as sub-cellular localization. Levels of gene expression are sometimes measured by linking a gene for GFP production to another gene.

Also, many biological molecules have an intrinsic fluorescence that can sometimes be used without the need to attach a chemical tag. Sometimes this intrinsic fluorescence changes when the molecule is in a specific environment, so the distribution or binding of the molecule can be measured. Bilirubin, for instance, is highly fluorescent when bound to a specific site on serum albumin. Bilirubin (formerly referred to as hematoidin) is the yellow breakdown product of normal Heme Catabolism. Zinc protoporphyrin, formed in developing red blood cells instead of hemoglobin when iron is unavailable or lead is present, has a bright fluorescence and can be used to detect these problems. Zinc protoporphyrin is a compound found in Red blood cells when Heme production is inhibited by Lead.

As of 2006, the number of fluorescence applications is growing in the biomedical biological and related sciences. Methods of analysis in these fields are also growing, albeit with increasingly unfortunate nomenclature in the form of acronyms such as: FLIM, FLI, FLIP, CALI, FLIE, FRET, FRAP, FCS, PFRAP, smFRET, FIONA, FRIPS, SHREK, SHRIMP, TIRF. Fluorescence lifetime imaging or FLIM is a powerful tool for producing an image based on the differences in the exponential decay rate of the Fluorescence from a fluorescent Fluorescence Loss in Photobleaching, or FLIP, is a technique in Fluorescence microscopy which can be used to examine the movement or diffusion of molecules inside Förster resonance energy transfer (abbreviated FRET) also known as Fluoresence resonance energy transfer or resonance energy transfer ( RET right|thumb|320px|Principle of FRAP Fluorescence recovery after Photobleaching (FRAP denotes an optical technique capable of quantifying the two dimensional lateral Fluorescence correlation spectroscopy ( FCS) is a common technique used by physicists chemists and biologists to experimentally characterize the dynamics of fluorescent species Most of these techniques rely on fluorescence microscopes. These microscopes use high intensity light sources, usually mercury or xenon lamps, LEDs, or lasers, to excite fluorescence in the samples under observation. Optical filters then separate excitation light from emitted fluorescence, to be detected by eye, or with a (CCD) camera or other light detectors (photomultiplier tubes, spectrographs, etc). Much research is underway to improve the capabilities of such microscopes, the fluorescent probes used, and the applications they are applied to. Of particular note are confocal microscopes, which use a pinhole to achieve optical sectioning – affording a quantitative, 3D view of the sample.

Gemology, mineralogy, geology and forensics

Gemstones, minerals, fibers and many other materials which may be encountered in forensics or with a relationship to various collectibles may have a distinctive fluorescence or may fluoresce differently under short-wave ultraviolet, long-wave ultra violet, or X-rays. A gemstone or gem, also called a precious or semi-precious stone, is a piece of attractive Mineral, which &mdash when cut and polished &mdash A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific Fiber or fibre is a class of Materials that are continuous filaments or are in discrete elongated pieces similar to lengths of thread. For the record label see Collectables Records For the Ashanti album see Collectables by Ashanti A collectable X-radiation (composed of X-rays) is a form of Electromagnetic radiation.

Many types of calcite and amber will fluoresce under shortwave UV. Calcite is a carbonate mineral and the most stable polymorph of Calcium carbonate ( Ca[[carbon C]] O 3 Rubies, emeralds, and the Hope Diamond exhibit red fluorescence under short-wave UV light; diamonds also emit light under X ray radiation. A Ruby is a pink to blood-red Gemstone, a variety of the Mineral Corundum ( Aluminium oxide) Emeralds are a variety of the Mineral Beryl (Be3Al2(SiO36 colored Green by trace amounts French Blue redirects here For the color see Blue. The Hope Diamond is a large 45 X-radiation (composed of X-rays) is a form of Electromagnetic radiation.

Crude oil (petroleum) fluoresces in a range of colors, from dull brown for heavy oils and tars through to bright yellowish and bluish white for very light oils and condensates. Petroleum ( L petroleum, from Greek πετρέλαιον, lit This phenomenon is used in oil exploration drilling to identify very small amounts of oil in drill cuttings and core sample. Hydrocarbon exploration (or oil and gas exploration) is the search by petroleum Geologists for Hydrocarbon deposits beneath the Earth's surface

Organic liquids

Organic liquids such as mixtures of anthracene in benzene or toluene, or stilbene in the same solvents, fluoresce with ultraviolet or gamma ray irradiation. Anthracene is a solid Polycyclic aromatic hydrocarbon consisting of three fused Benzene rings derived from Coal-tar. Benzene, or benzol, is an organic Chemical compound and a known Carcinogen with the molecular formula C 6 H 6 Toluene, also known as methylbenzene or phenylmethane, is a clear water -insoluble liquid with the typical smell of Paint thinners redolent of Stilbene may refer to (E-Stilbene (Z-Stilbene A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions Irradiation is the process by which an item is exposed to Radiation. The decay times of this fluorescence is of the order of nanoseconds since the duration of the light depends on the lifetime of the excited states of the fluorescent material, in this case anthracene or stilbene.

See also

• Absorption-re-emission atomic line filters use the phenomenon of fluorescence to filter light extremely effectively. An atomic line filter (ALF is an advanced optical Band-pass filter used in the Physical sciences for filtering Electromagnetic radiation
• Black light
• Blacklight paint
• Fluorescence correlation spectroscopy
• Fluorescence in plants: natural and modified
• Fluorescence spectroscopy
• Fluorescent multilayer card
• Fluorescent Multilayer Disc
• Fluorescent lamp
• Fluorometer
• High-visibility clothing
• Laser-induced fluorescence
• List of light sources
• Phosphorescence
• X-ray fluorescence

References

External links

• [1] Fluorescence Applications & Instruments Slideshows | HORIBA Jobin Yvon
• Interactive Fluorescence Dye and Filter Database Carl Zeiss Interactive Fluorescence Dye and Filter Database. A Black light or UV Light is a lamp emitting Electromagnetic radiation that is almost exclusively in the soft near ultraviolet range and emits "Dayglo" redirects here For other meanings see Dayglo (disambiguation. Fluorescence correlation spectroscopy ( FCS) is a common technique used by physicists chemists and biologists to experimentally characterize the dynamics of fluorescent species All Plants, Algae, and Cyanobacteria are naturally Fluorescent, since Chlorophyll a is fluorescent Fluorescence spectroscopy aka fluorometry or spectrofluorometry is a type of Electromagnetic spectroscopy which analyzes Fluorescence from a sample Using the same 3D optical data storage technology as the Fluorescent multilayer disc, the fluorescent multilayer card was a memory device proposed by Consallation3D Fluorescent Multilayer Disc ( FMD) was an Optical disc format developed by Constellation 3D that uses fluorescent, rather than reflective A fluorescent lamp or fluorescent tube is a Gas-discharge lamp that uses Electricity to excite mercury Vapor. A fluorometer or fluorimeter is a device used to measure parameters of Fluorescence: its intensity and Wavelength distribution of Emission spectrum High-visibility clothing, a type of Personal protective equipment (PPE is any Clothing worn that has highly reflective properties or a color that is easily For other uses see LIF. Laser-induced fluorescence (LIF is a spectroscopic method used for studying structure of molecules detection This is a list of sources of Light, including both natural and artificial sources and both processes and devices. Phosphorescence is a specific type of Photoluminescence related to fluorescence. X-ray fluorescence (XRF is the emission of characteristic "secondary" (or fluorescent X-rays from a material that has been excited by bombarding with high-energy
• ISS Fluorescence Lifetime Standards Tables
• ISS Fluorescence Probes Data Tables
• The Fluorescence Foundation
• Fluorophores.org The database of fluorescent dyes
• Jablonski diagram
• Fluorescence on Scienceworld
• Basic Concepts in Fluorescence
• Scorpion detection using UV LEDs
• Immunofluorescence Protocol
• An example of use of fluorescence in generating cellular images
• More examples how the fluorescence can be used
• Fluorescence in digital Photography
• The Influence of Fluorescence in the World of Art
• Fluorescence control by Photonic Crystals - ICMM
• The Fluorescent Mineral Society
• Laboratory for Fluorescence Dynamics
• Exitation and emmision spectra of various fluorescent dyes