A hydrophile , from the Greek language Greek hydros water and philia love, is a molecule or other molecular entity that is attracted to, and tends to be dissolved by water. A hydrophilic molecule or portion of a molecule is one that has a tendency to interact with or be dissolved by water and other polar substances. ref definition of http goldbook.iupac.org H02906.html hydrophilic and http goldbook.iupac.org HT06963.html hydrophilicity from IUPAC. Compendium of Chemical Terminology, 2nd ed. the Gold Book . Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford 1997 . XML on line corrected version http goldbook.iupac.org 2006 created by M. Nic, J. Jirat, B. Kosata updates compiled by A. Jenkins. ISBN 0 9678550 9 8. doi 10.1351 goldbook. ref ref http www.merriam webster.com dictionary hydrophilic Merriam Webster dictionary ref This is Thermodynamics thermodynamic ally favorable, and makes these molecules soluble not only in water, but also in other Solvent Solvent classifications polar solvents . There are hydrophilic and hydrophobic parts of the cell membrane . A hydrophilic molecule or portion of a molecule is one that is typically charge polarized and capable of hydrogen bond ing, enabling it to dissolve more readily in water than in oil or other hydrophobic solvents. Hydrophilic and hydrophobic molecules are also known as polar molecules and nonpolar molecule s, respectively. Some hydrophilic substances do not dissolve. This type of mixture is called a colloid . Soap , which is amphipathic , has a hydrophilic head and a hydrophobic tail, allowing it to dissolve in both waters and oils. An approximate rule of thumb for hydrophilicity of organic compounds is that solubility of a molecule in water is more than 1 Concentration Mass percentage fraction mass if there is at least one neutral hydrophile group per 5 carbons, or at least one electrically charged hydrophile group per 7 carbons. ref name Pedersen Medical Chemistry Compendium ... more details
In chemistry, protonation is the addition of a proton H sup sup to an atom , molecule , or ion . Protonation is the reverse of deprotonation . Protonation is possibly the most fundamental chemical reaction and is a step in many stoichiometry stoichiometric and catalysis catalytic processes . Some ions and molecules can undergo more than one protonation and are labeled polybasic. This is true of many biological macromolecule s. Upon protonating a substrate, the mass and the charge of the species each increase by one unit. Protonating or deprotonating a molecule or ion alters many chemical properties beyond the change in the charge and mass hydrophile hydrophilicity , reduction potential , Ultraviolet visible spectroscopy optical properties , among others. Protonation is also an essential step in certain analytical procedures such as electrospray mass spectrometry . Protonation and deprotonation occur in most acid base reaction s they are the core of most acid base reaction theories. A Br nsted Lowry acid base theory Bronsted Lowry acid is defined as a chemical substance that protonates another substance. Rates of protonation and deprotonation Protonations are often rapid, in part because of the high mobility of protons in water. The reaction rate rate of protonation is related to the acidity of the protonated species. Weak acids deprotonate more slowly than strong acids. The rates of protonation and deprotonation can be especially slow when protonation induces significant structural changes. Reversibility and catalysis Usually, protonations are reversible and the conjugate base is unchanged by being protonated. In some cases, however, protonation causes isomerization. Cis alkene s can be converted to trans alkenes using a catalytic amount of protonating agent. Many enzymes, such as the serine hydrolase s operate by mechanisms that involve reversible protonations of substrates. See also Deprotonation References reflist Unreferenced date January 2009 Category Chemical ... more details
lowercase Fluids Home is a computer simulation of two phase flow behavior in microgravity and microfluidics ref cite web url http news.uns.purdue.edu html4ever 2004 040107.Ladisch.chip.html title Purdue engineers develop quick, inexpensive method to prototype microchips publisher News.uns.purdue.edu date 2004 01 07 accessdate 2011 02 20 ref problems at Purdue University , using the Surface Evolver program. About The project s purpose is to develop better methods for the management of liquid rocket propellant s in microgravity, ref cite web url http news.uns.purdue.edu x 2007b 070905CollicottSatellites.html title Engineers rescue aging satellites, saving millions publisher News.uns.purdue.edu date 2007 09 05 accessdate 2011 02 20 ref ref cite web url http news.uns.purdue.edu insidepurdue 2009 090716 ResearchCollicott.html title Research focuses on fuel injection in rockets publisher News.uns.purdue.edu date 2009 07 16 accessdate 2011 02 20 ref and to investigate two phase flow in microelectromechanical systems , taking into account factors like surface tension . Systems can then be designed that use electrowetting , channel geometry , and Hydrophobe hydrophobic or Hydrophile hydrophilic coating s to allow the smooth passage of fluids. Such systems would include compact medical device s, biosensor s, ref cite web url http news.uns.purdue.edu x 2009a 090421WereleyChips.html title Innovation could make lab on a chip devices easier to use, cheaper to make publisher News.uns.purdue.edu date 2009 04 21 accessdate 2011 02 20 ref and fuel cell s, to name a few. Computing platform It uses the Berkeley Open Infrastructure for Network Computing BOINC distributed computing platform. Application notes There is no screen saver. Work unit Central processing unit CPU times are generally less than 20 hours. Work units average in size around 500 Kilobyte kB . You have to run many work units to get levels of credit comparable to SETI Home or Climateprediction.net distributed programs. ... more details
Poloxamer 407 is a hydrophile hydrophilic non ion ic surfactant of the more general class of copolymers known as poloxamer s. Poloxamer 407 is a triblock copolymer consisting of a central hydrophobic block of polypropylene glycol flanked by two hydrophilic blocks of polyethylene glycol . The approximate lengths of the two PEG blocks is 101 repeat units while the approximate length of the propylene gycol block is 56 repeat units. This particular compound is also known by the BASF trade name Pluronic F127. Uses of poloxamer 407 Most of the common uses of poloxamer 407 are related to its surfactant properties. For example, it is widely used in cosmetics for dissolving oily ingredients in water. It can also be found in multi purpose contact lens cleaning solutions, where its purpose there is to help remove lipid films from the lens. It can also be found in some mouthwashes. Reports of adverse effects It was reported in The Australian newspaper 18 November 2006 that this common ingredient in toothpaste and mouthwash can cause high cholesterol ref http www.theaustralian.com.au news health science dental hygiene gives you a brush with cholesterol story e6frg8y6 1111112544182 ref . A team from the Centre for Ageing and the ANZAC Research Institute in Sydney found that when P407 was given to mice, it coated cells in the liver that control cholesterol levels, leading to a 10 fold increase in levels. The amounts given were not reported in the article. Cited References Reflist External links http www.pharma solutions.basf.com xfeizn55oc4xx1rwwu13fh3v product detail.aspx?PrID Lutrol F 127&GrpID 49 BASF page on Lutrol F 127 Dead link date September 2009 http www.tomsofmaine.com products ingredient detail.aspx?id 14&name Poloxamer 20407 Ingredient Fact Sheet Poloxamer 335 and 407 from Tom s of Maine http chemsub.online.fr name Poloxamer 407.html ChemSub Online Poloxamer 407 Chemistry stub Category Non ionic surfactants ... more details
chembox ImageFile Butanetriol.png ImageSize IUPACName Butane 1,2,4 triol OtherNames 1,2,4 Butanetriol br 1,2,4 Trihydroxybutane br Triol 124 br 2 Deoxyerthritol Section1 Chembox Identifiers Abbreviations ChemSpiderID 17287 SMILES1 OCCC O CO InChIKey ARXKVVRQIIOZGF UHFFFAOYAQ StdInChI 1S C4H10O3 c5 2 1 4 7 3 6 h4 7H,1 3H2 StdInChIKey ARXKVVRQIIOZGF UHFFFAOYSA N CASNo 3068 00 6 EINECS 221 323 5 PubChem SMILES OCC O CCO InChI 1 C4H10O3 c5 2 1 4 7 3 6 h4 7H,1 3H2 RTECS EK7176000 MeSHName ChEBI KEGG ATCCode prefix ATCCode suffix ATC Supplemental Section2 Chembox Properties C 4 H 10 O 3 Appearance Density 1.19 MeltingPt Melting notes BoilingPt 190 191 C Boiling notes 18 torr Solubility SolubleOther Solvent pKa pKb Section7 Chembox Hazards ExternalMSDS EUClass EUIndex MainHazards NFPA H 2 NFPA F 1 NFPA R 0 NFPA O RPhrases R36 SPhrases S24 25 RSPhrases FlashPt 112 C Autoignition ExploLimits PEL 1,2,4 Butanetriol is a clear or slightly yellow, odorless, hygroscopic , flammable, viscosity viscous liquid. It is an alcohol with three Hydrophile hydrophilic alcohol ic hydroxyl group s. It is similar to glycerol and erythritol . It is Chirality chemistry chiral , with two possible enantiomer s. 1,2,4 Butanetriol is used in the manufacture of 1,2,4 Butanetriol trinitrate butanetriol trinitrate BTTN , an important military propellant . 1,2,4 Butanetriol is also used as a precursor for two cholesterol lowering drugs, Crestor and Zetia which are derives from D 3,4 dihydroxybutanoic acid, by using 3 hydroxy gamma butyrolactone as a chiral synthon cite journal last1 Niu first1 W year 2003 title Microbial synthesis of the energetic material precursor 1,2,4 butanetriol journal Am. Chem. Soc. year 2003 volume 125 issue 43 pages 12998 12999 url http pubs.acs.org doi abs 10.1021 ja036391 2B cite web url http www.frostchemlab.com biosynthetic pathways.htm title Biosynthetic Pathways accessdate 24 November 2010 . It is as one of the monomers for manufacture of some polyester s and as a ... more details
and retain water. An ultradeformable and highly hydrophile hydrophilic vesicle always seeks to avoid ... usage in drug delivery consequently relies on the carrier s ability to widen and overcome the hydrophile ... more details
Refimprove date March 2009 File PinkBathrobe.JPG thumb right A pink bathrobe consensus agree with this img A bathrobe , dressing gown or housecoat is a robe . A bathrobe is usually made from towelling or other absorbent fabric, and may be donned while wet, serving both as a towel and an informal garment . A dressing gown for men or a housecoat for women is a loose, open fronted gown closed with a fabric belt that is put on over nightwear on rising from bed, or, less commonly today, worn over some day clothes when partially dressed or undressed in the morning or evening for example, over a man s shirt and trousers without jacket and tie . The regular wearing of a dressing gown by men about the house is derived from the 18th century wearing of the banyan clothing banyan in orientalism orientalist imitation. ref In 1888, Coffignon describes it an Armenian clothing which started to be worn under Louis XV , costume arm nien qui commen a tre port sous le r gne de Louis XV Les coulisses de la mode. Paris vivant , p.123. A la librairie illustr e ref The Japanese clothing Japanese yukata is an unlined, cotton kimono worn as a bathrobe or as summer outdoor clothing. Several styles of bathrobes are marketed to consumers, categorised by textile material and type of weave. Styles of fabrics Bathrobes are generally made of four different fabrics. ref http www.bathrobes.net ?p 23 ref Cotton Cotton is a natural fibre consisting primarily of cellulose and is one of the most commonly used fibres in textile manufacturing. Due to the hydrophile hydrophilic nature of cellulose, cotton absorb water easily and are frequently used by the beach, pool, or following a shower. Cotton robes are especially suited to use in hot climates because cotton tends to absorb perspiration . Silk Another common fabric used in robes is silk . Silk is a fine lustrous fibre composed mainly of fibroin and produced by the secretions of certain insect larvae normally silkworms forming strong, elastic, fibrou ... more details
Image Frap diagram.svg right thumb 320px Principle of FRAP A The bilayer is uniformly labeled with a fluorescent tag B This label is selectively photobleached by a small 30 micrometre fast light pulse C The intensity within this bleached area is monitored as the bleached dye diffuses out and new dye diffuses in D Eventually uniform intensity is restored Fluorescence recovery after photobleaching FRAP denotes an optical technique capable of quantifying the two dimensional lateral diffusion of a molecularly thin film containing fluorescently labeled probes, or to examine single cells. This technique is very useful in biological studies of cell membrane diffusion and protein binding. In addition, surface deposition of a fluorescing phospholipid bilayer or monolayer allows the characterization of hydrophile hydrophilic or hydrophobe hydrophobic surfaces in terms of surface structure and free energy. Similar, though less well known, techniques have been developed to investigate the 3 dimensional diffusion and binding molecular binding of molecules inside the cell they are also referred to as FRAP. Experimental Setup The basic apparatus comprises an optical microscope , a List of light sources light source and some fluorescent probe. Fluorescence Fluorescent emission is contingent upon absorption of a specific optical wavelength or color which restricts the choice of lamps. Most commonly, a broad spectrum mercury element mercury or xenon source is used in conjunction with a color filter. The technique begins by saving a background image of the sample before photobleaching. Next, the light source is focused onto a small patch of the viewable area either by switching to a higher magnification microscope objective or with laser light of the appropriate wavelength. The fluorophores in this region receive high intensity illumination which causes their fluorescence lifetime to quickly elapse limited to roughly 10 sup 5 sup photons before extinction . Now the image in the micros ... more details
Micellar electrokinetic chromatography MEKC , is a chromatography technique, used in analytical chemistry . It is a modification of capillary electrophoresis CE , where the samples are separated by differential partitioning between micelles pseudo stationary phase and a surrounding aqueous buffer solution mobile phase . ref Terabe, S. Otsuka, K. Ichikawa, K. Tsuchiya, A. Ando, T. Anal. Chem . 1984 , 56 , 111. ref The basic set up and detection methods used for MEKC are the same as those used in CE. The difference is that the solution contains a surfactant at a concentration that is greater than the critical micelle concentration CMC . Above this concentration, surfactant monomers are in chemical equilibrium equilibrium with micelles. In most applications, MEKC is performed in open capillaries under alkaline conditions to generate a strong electro osmosis electroosmotic flow . Sodium dodecyl sulfate SDS is the most commonly used surfactant in MEKC applications. The anionic character of the sulfate groups of SDS cause the surfactant and micelles to have electrophoresis electrophoretic mobility that is counter to the direction of the strong electroosmotic flow . As a result, the surfactant monomers and micelles migrate quite slowly, though their net movement is still toward the cathode . ref Baker, D.R. Capillary Electrophoresis John Wiley & Sons, Inc. New York, 1995 . ref During a MEKC separation, analyte s distribute themselves between the hydrophobe hydrophobic interior of the micelle and hydrophile hydrophilic buffer solution as shown in figure 1 . Image MEKC.gif frame Figure 1 Depiction of the distribution of analytes A based on their hydrophobicity. Analytes that are soluble insoluble in the interior of micelles should migrate at the electroosmotic flow velocity, math u o math , and be detected at the retention time of the buffer, math t M math . Analytes that solubilize completely within the micelles analytes that are highly hydrophobic should migrate at the mic ... more details
Second messengers are molecules that relay signals from receptors on the cell surface to target molecules inside the cell, in the cytoplasm or nucleus. They relay the signals of hormones like epinephrine adrenalin , growth factors, and others, and cause some kind of change in the activity of the cell. They greatly amplify the strength of the signal. ref name Kimball cite web author Kimball, J title Second messengers url http users.rcn.com jkimball.ma.ultranet BiologyPages S Second messengers.html ref ref MeshName Second Messenger Systems ref Secondary messengers are a component of signal transduction cascades. Earl Wilbur Sutherland, Jr. , discovered second messengers, for which he won the 1971 Nobel Prize in Physiology or Medicine. Sutherland saw that epinephrine would stimulate the liver to convert glycogen to glucose sugar in liver cells, but epinephrine alone would not convert glycogen to glucose. He found that epinephrine had to trigger a second messenger, cyclic AMP , for the liver to convert glycogen to glucose. ref name Campbell cite book author Reece, Jane Campbell, Neil title Biology publisher Benjamin Cummings location San Francisco year 2002 pages isbn 0 8053 6624 5 oclc doi accessdate ref Secondary messenger systems can be synthesized and activated by enzymes, like the cyclases that synthesize cyclic nucleotides, or by opening of ion channels to allow influx of metal ions, like Ca sup 2 sup signaling. These small molecules bind and activate protein kinases, ion channels, and other proteins, thus continuing the signaling cascade. Types of secondary messenger molecules There are three basic types of secondary messenger molecules hydrophobe Hydrophobic molecules water insoluble molecules, like diglyceride diacylglycerol , and phosphatidylinositol s, which are membrane associated and diffuse from the plasma membrane into the intermembrane space where they can reach and regulate membrane associated effector protein s hydrophile Hydrophilic molecules water so ... more details
chembox verifiedrevid 413501846 ImageFile Methyl cellulose.png ImageSize 200px IUPACName OtherNames Cellulose, methyl ether methylated cellulose methylcellulose E461 Section1 Chembox Identifiers CASNo 9004 67 5 PubChem SMILES Section2 Chembox Properties Formula variable MolarMass variable Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Methyl cellulose or methylcellulose is a chemical compound derived from cellulose . It is a hydrophile hydrophilic white powder in pure form and dissolves in cold but not in hot water, forming a clear viscous solution or gel. It is sold under a variety of trade names and is used as a thickener and emulsifier in various food and cosmetic products, and also as a treatment of constipation . Like cellulose, it is not digestible, not toxic, and not allergenic . Chemistry Methyl cellulose does not occur naturally and is synthetically produced by heating cellulose with caustic solution e.g. a solution of sodium hydroxide and treating it with methyl chloride . In the substitution reaction that follows, the hydroxyl residues OH functional groups are replaced by methoxide OCH sub 3 sub groups . Different kinds of methyl cellulose can be prepared depending on the number of hydroxyl groups substituted. Cellulose is a polymer consisting of numerous linked glucose molecules, each of which exposes three hydroxyl groups. The Degree of Substitution DS of a given form of methyl cellulose is defined as the average number of substituted hydroxyl groups per glucose. The theoretical maximum is thus a DS of 3.0, however more typical values are 1.3 2.6. Different methyl cellulose preparations can also differ in the average length of their polymer backbones. Solubility and temperature Methyl cellulose has a lower critical solution temperature LCST between 40 C and 50 C. At temperatures below the LCST, it is readily solubility soluble in water above the LCST, it is not soluble, which has a paradoxical ... more details
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