|Other names||Fluorescein, resorcinolphthalein, C. I. 45350, solvent yellow 94, D & C yellow no. 7, angiofluor, Japan yellow 201, soap yellow, Pyoverdin|
|Molar mass||332. CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to PubChem is a Database of chemical Molecules The system is maintained by the National Center for Biotechnology Information (NCBI a component The EINECS number (for European Inventory of Existing Chemical Substances) is a registry number given to each Chemical substance commercially available in the Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 306 g/mol|
314 - 316 °C
|Solubility in water||Slightly|
|Except where noted otherwise, data are given for|
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references
Fluorescein is a fluorophore commonly used in microscopy, in a type of dye laser as the gain medium, in forensics and serology to detect latent blood stains, and in dye tracing. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Water is a common Chemical substance that is essential for the survival of all known forms of Life. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly A fluorophore, in analogy to a Chromophore, is a component of a molecule which causes a molecule to be Fluorescent. Microscopy is the technical field of using microscopes to view samples or objects A dye laser is a Laser which uses an organic Dye as the Lasing medium, usually as a Liquid Solution. The active laser medium or gain medium is the source of optical Gain within a Laser. Serology is the scientific study of blood serum. In practice the term usually refers to the Diagnostic identification of antibodies in the serum Dye tracing is tracking and tracing various Flows using Dye added to the Liquid in question Fluorescein has an absorption maximum at 494 nm and emission maximum of 521 nm (in water). In Physics, absorption of electromagnetic radiation is the process by which the Energy of a Photon is taken up by matter typically the electrons of an Fluorescence is a Luminescence that is mostly found as an Also, fluorescein has an isosbestic point (equal absorption for all pH values) at 460 nm. In Spectroscopy, an isosbestic point is a specific Wavelength at which two (or more chemical species have the same Molar absorptivity (&epsilon pH is the measure of the acidity or alkalinity of a Solution. Fluorescein is also known as a color additive (D&C Yellow no. The United States Federal Food Drug and Cosmetic Act (abbreviated as FFDCA FDCA or FD&C is a set of laws passed by Congress in 1938 giving authority to the 7). The disodium salt form of fluorescein is known as D&C Yellow no. The United States Federal Food Drug and Cosmetic Act (abbreviated as FFDCA FDCA or FD&C is a set of laws passed by Congress in 1938 giving authority to the 8.
The fluorescence of this molecule is very high, and excitation occurs at 494 nm and emission at 521. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays A nanometre ( American spelling: nanometer, symbol nm) ( Greek: νάνος nanos dwarf; μετρώ metrό count) is a
Fluorescein has a pKa of 6. 4 and its ionization equilibrium leads to pH dependent absorption and emission over the range of 5 to 9. In Physics, absorption of electromagnetic radiation is the process by which the Energy of a Photon is taken up by matter typically the electrons of an Fluorescence is a Luminescence that is mostly found as an Also, the fluorescence lifetimes of the protonated and deprotonated forms of fluorescein are approximately 3 and 4 ns, which allows for pH determination from non-intensity based measurements. The lifetimes can be recovered using time-correlated single photon counting or phase-modulation fluorimetry.
There are many fluorescein derivatives, for example fluorescein isothiocyanate, often abbreviated as FITC. Fluorescein isothiocyanate (FITC is a derivative of Fluorescein used in wide-ranging applications including Flow cytometry. FITC is the original fluorescein molecule functionalized with an isothiocyanate group (-N=C=S), replacing a hydrogen atom on the bottom ring of the structure. Isothiocyanate is the Chemical group - N = C = S, formed by substituting Sulfur for Oxygen in the Isocyanate Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 This derivative is reactive towards amine groups on proteins inside cells. Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. A succinimidyl-ester functional group attached to the fluorescein core, creating NHS-fluorescein, forms another common amine reactive derivative.
Other derivatives of fluorescein include Oregon Green, Tokyo Green, SNAFL, and carboxynaphthofluorescein. These derivatives, along with newer fluors such as Alexa 488 and DyLight 488, have been tailored for various chemical and biological applications where higher photostability, different spectral characteristics, or different attachment groups are needed. History The Alexa Fluor dyes were named after Alex Haugland son of the founders of Molecular Probes Richard and Rosaria Haugland Photobleaching is the photochemical destruction of a Fluorophore.
Fluorescein can be prepared from phthalic anhydride and resorcinol in the presence of zinc chloride via the Friedel-Crafts reaction. Phthalic anhydride is the Organic compound with the formula C6H4(CO2O Resorcinol (or resorcin) is a Chemical compound from the dihydroxy Phenols it is the 13- Isomer of Benzenediol. Zinc chloride is the name of Chemical compound with the formula Zn[[chlorine Cl]]2 and its hydrates The Friedel-Crafts reactions are a set of reactions developed by Charles Friedel and James Crafts in 1877.
A second method to prepare fluorescein uses methanesulfonic acid as a Lewis acid and as the catalyst. Methanesulfonic acid is a colorless liquid with the chemical formula CH4O3S This route has a high yield under milder conditions.  
One of its more recognizable uses was in the Chicago River, where fluorescein was the first substance used to dye the river green on St. Patrick's Day in 1962. The Chicago River is 156 miles (251 km long and flows through downtown Chicago. Saint Patrick's Day (Lá ’le Pádraig or Lá Fhéile Pádraig) colloquially St In 1966 environmentalists forced a change to a vegetable based dye to protect the thousands of goldfish that populate the river.
Other uses of fluorescein include using it as a water-soluble dye added to rainwater in environmental testing simulations to aid in locating and analyzing any water leaks, and in Australia and New Zealand as a methylated spirit dye. Rain is Liquid precipitation. On Earth it is the condensation of atmospheric Water vapor into drops heavy enough to fall often making it to Denatured alcohol is Ethanol which has been rendered toxic or otherwise undrinkable and in some cases dyed
In cellular biology, the isothiocyanate derivative of fluorescein is often used to label and track cells in fluorescence microscopy applications (for example, flow cytometry). Isothiocyanate is the Chemical group - N = C = S, formed by substituting Sulfur for Oxygen in the Isocyanate The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called A fluorescence microscope (colloquially synonymous with epifluorescent microscope) is a light Microscope used to study properties of organic or inorganic substances Flow cytometry is a technique for counting examining and sorting microscopic particles suspended in a stream of fluid Additional biologically active molecules (such as antibodies) may also be attached to fluorescein, allowing biologists to target the fluorophore to specific proteins or structures within cells. Antibodies (also known as immunoglobulins, abbreviated Ig) are Gamma globulin Proteins that are found in Blood or other Bodily This application is common in yeast display. Yeast display (or yeast surface display) is a technique used in the field of Protein engineering.
Fluorescein can also be conjugated to nucleoside triphosphates and incorporated into a probe for in situ hybridisation. Nucleoside triphosphate (NTP is a Nucleoside with three Phosphates Natural nucleoside triphosphates include Adenosine triphosphate (ATP Guanosine In Molecular biology, a hybridization probe is a fragment of DNA or RNA of variable length (usually 100-1000 bases long which is used to detect in DNA In situ hybridization (ISH is a type of hybridization that uses a labeled Complementary DNA or RNA strand (i Fluorescein-labelled probes can be imaged using FISH, or targeted by antibodies using immunohistochemistry. FISH ( Fluorescent In situ hybridization) is a cytogenetic technique that can be used to detect and localize the presence or absence Antibodies (also known as immunoglobulins, abbreviated Ig) are Gamma globulin Proteins that are found in Blood or other Bodily Immunohistochemistry or IHC refers to the process of localizing proteins in cells of a tissue section exploiting the principle of antibodies binding specifically The latter is a common alternative to digoxigenin, and the two are used together for labelling two genes in one sample . Digoxigenin (DIG is a Steroid found exclusively in the flowers and leaves of the plants Digitalis purpurea and Digitalis lanata
Fluorescein sodium is used extensively as a diagnostic tool in the field of ophthalmology, and increasingly during surgery for brain tumors. Ophthalmology is the branch of Medicine which deals with the diseases and surgery of the visual pathways including the Eye, Brain A brain tumor is any intracranial Tumor created by abnormal and uncontrolled cell division, normally either in the Brain itself ( Neurons
In ophthalmology, fluorescein is applied topically in the form of an eye drop, given orally, or injected intravenously to produce a fluorescein angiogram.
In the process of removing foreign bodies from the eye, fluorescein-containing paper strips are employed by the practitioner to check the effectiveness of his operative procedure. Fluorescein Angiography, or fluorescent angiography, is a technique for examining the circulation of the Retina using the Dye tracing Typically, metal foreign bodies will leave a "rust ring" and this must be removed from the surface of the eye. These procedures refer solely to bodies which contact the cornea.
A type of curette called a "spud" is used to scrape the surface of the cornea until it is clean. Of course penetrating injuries do not fall into this kind of procedure which is typically employed in the practitioner's office. An ultraviolet source is used to fluoresce the dye, which is later lavaged from the eye after successful completion of the procedure.
A similar process is used to examine an eye which has sustained a "brushing" injury where a foreign object is not seen to enter the cornea, but rather cause an abrasion on the cornea. These usually heal completely in one or more days depending upon the severity of the abrasion.
It is apparent that the dye property of fluorescein is an important tool in a practitioner's office. It may be called into frequent use if the physician serves where industries employ any kind of grinding or similar operations which generate the kinds of missiles found to cause these injuries of the eye.
So it can be seen that topical fluorescein is a useful tool in the diagnosis of corneal abrasions, corneal ulcers, herpetic corneal infections, and dry eye. For corneal abrasions in dogs and cats see Corneal ulcer. Corneal abrasion is a medical condition involving the loss of the surface Epithelial See Corneal ulcers in animals for information about the condition in animals The Herpesviridae are a large family of DNA viruses that cause diseases in animals including humans Keratoconjunctivitis sicca (KCS, also called Keratitis sicca, sicca syndrome, Fluorescein angiography is used to diagnose and categorize macular degeneration, diabetic retinopathy, inflammatory intraocular conditions, and intraocular tumors. Fluorescein Angiography, or fluorescent angiography, is a technique for examining the circulation of the Retina using the Dye tracing Macular degeneration is a medical condition usually of older adults which results in a loss of vision in the center of the visual field (the Macula) because Diabetic retinopathy is Retinopathy (damage to the Retina) caused by complications of Diabetes mellitus, which can eventually lead to Blindness See also Cancer A tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells (termed neoplastic
Topical, oral, and intravenous use of fluorescein can cause adverse reactions including nausea, vomiting, hives, acute hypotension, anaphylaxis and related anaphylactoid reaction, cardiac arrest, and sudden death. In Medicine, an adverse effect is a harmful and undesired effect resulting from a medication or other intervention such as Chemotherapy or Surgery. Nausea ( Latin: Nausea, Greek:, " Sea-sickness " also called wamble) is the sensation of unease and discomfort Vomiting (also called throwing up, emesis) is the forceful expulsion of the contents of one's Stomach through the Mouth and sometimes the In Medicine, an acute disease is a disease with either or both of a rapid onset a short course (as opposed to a chronic course In Physiology and Medicine, hypotension refers to an abnormally low Blood pressure. Anaphylaxis is an acute systemic (multi-system and severe Type I Hypersensitivity allergic reaction in humans and other Mammals Anaphylaxis is an acute systemic (multi-system and severe Type I Hypersensitivity allergic reaction in humans and other Mammals A cardiac arrest, also known as cardiorespiratory arrest, cardiopulmonary arrest or circulatory arrest, is the abrupt cessation of normal circulation of  Intravenous use has the most reported adverse reactions, including sudden death, but this may reflect greater use rather than greater risk. Both oral and topical uses have been reported to cause anaphylaxis, including one case of anaphylaxis with cardiac arrest (resuscitated) following topical use in an eye drop.  Reported rates of adverse reactions vary from 1% to 6% The higher rates may reflect study populations that include a higher percentage of persons with prior adverse reactions. The risk of an adverse reaction is 25 times higher if the person has had a prior adverse reaction.  The risk can be reduced with prior (prophylactic) use of antihistamines and prompt emergency management of any ensuing anaphylaxis. Prophylaxis ( Greek "προφυλάσσω" to guard or prevent beforehand) is any medical or Public health procedure whose purpose A histamine antagonist is an agent which serves to inhibit the release or action of Histamine.  A simple prick test may help to identify persons at greatest risk of adverse reaction. 
The most common adverse reaction is nausea, due to a difference in the pH from the body and the pH of the sodium fluorescein dye. The nausea usually is transient and subsides quickly. Hives can range from a minor annoyance to severe. A single dose of antihistamine may give complete relief. Anaphylactic shock and subsequent cardiac arrest and sudden death are very rare but because they occur within minutes, a health care provider who uses fluorescein should be prepared to perform emergency resuscitation.