Molecules/Elements/Particles

 

Tuesday
Aug232011

Morphine

"Morphine, C17H19NO3, is the most abundant of opium’s 24 alkaloids, accounting for 9 to 14% of opium-extract by mass. Named after the Roman god of dreams, Morpheus, who also became the god of slumber, the drug morphine, appropriately enough, numbs pain, alters mood and induces sleep. Less popular and less mentioned effects include nausea, vomiting and decreased gastrointestinal motility. (It’s a great constipator, and in Guerin’s painting, Isis is perhaps bringing Morpheus a laxative.) Morphine and its related synthetic derivatives, known as opioids, are so far unbeatable at dulling chronic or so-called “slow” pain, but unfortunately they are all physically addictive."

Monday
Aug222011

Vanillin

"Vanillin is a single molecule, 4-hydroxy-3-methoxybenzaldehyde (much easier to call it Vanillin), whose structure is shown in the image on the right. It's a white crystalline solid, which melts at 81°C. Vanilla planifola is an orchid which produces seed pods from which vanilla extracts are obtained; these extracts contain nearly 200 different molecules, of which vanillin is the most important, and most abundant, making up 98% of the eventual vanilla extract. Vanillin itself was first isolated from vanilla pods by Nicholas-Theodore Gobley in 1858 (though he thought that its formula was C10H6O2, not C8H8O2). The biosynthetic pathway starts with phenylalanine."

Sunday
Aug212011

EDTA--EthyleneDiamineTetraAcetic Acid

"Ethylenediaminetetraacetic acid, widely abbreviated as EDTA (for other names, see Table), is a polyamino carboxylic acid and a colourless, water-soluble solid. Its conjugate base is named ethylenediaminetetraacetate. It is widely used to dissolve limescale. Its usefulness arises because of its role as a hexadentate ("six-toothed") ligand and chelating agent, i.e. its ability to "sequester" metal ions such as Ca2+ and Fe3+. After being bound by EDTA, metal ions remain in solution but exhibit diminished reactivity. EDTA is produced as several salts, notably disodium EDTA and calcium disodium EDTA."

Saturday
Aug202011

Sodium Lauryl Sulfate

"It is the main component of most soap-based products, and if you were to look in your bathroom you're guaranteed to find at least one product containing it, for example, your shampoo or toothpaste [2]. In industry it will be found in engine degreasers or carpet cleaners, for example. It's inexpensive and an excellent foaming agent. It has a high pH as it is an alkali substance and has the appearance of a white powder."

"Sodium lauryl sulfate is a surfactant, which means a molecule that has ampiphilic properties. This means the sulfate head group (shown by the pink shading in the diagram below) is hydrophilic and water soluble, while the 12-carbon-long chain is hydrophobic and water insoluble. It is an anionic surfactant as defined by the sulfate head group, since it has a negative charge. The head group must be sufficiently soluble in water to be classed as a surfactant [2,3]."

Friday
Aug192011

Aspartame

"Aspartame is an artificial, non-saccharide sweetener used as a sugar substitute in some foods and beverages. In the European Union, it is codified as E951. Aspartame is a methyl ester of the aspartic acid/phenylalanine dipeptide. It was first sold under the brand name NutraSweet; since 2009 it also has been sold under the brand name AminoSweet. It was first synthesized in 1965 and the patent expired in 1992."

Thursday
Aug182011

Folic Acid

"Folic acid (vitamin B9) is important in a number of human metabolic pathways as well as being needed for nucleic acid synthesis, growth and the healthy development of a foetus [1]. Folic acid can be absorbed from the diet, with the highest levels of folic acid being found in foods such as meat extracts (e.g. Bovril), yeast extracts (e.g. Marmite), liver, asparagus, brussel sprouts, spinach, as well as being available as supplements [1]. Recently cereals and bread have been fortified with folic acid to try and eliminate folic acid deficiency especially in pregnant women."

Wednesday
Aug172011

Sulfanilamide

"Sulfanilamide (also spelled sulphanilamide) is a sulfonamide antibacterial. Chemically, it is a molecule containing the sulfonamide functional group attached to an aniline. As a sulfonamide antibiotic, it functions by competitively inhibiting (i.e., by acting as a substrate analogue) enzymatic reactions involving para-aminobenzoic acid (PABA).[1] PABA is needed in enzymatic reactions that produce folic acid which acts as a coenzyme in the synthesis of purine, pyrimidine and other amino acids."

Tuesday
Aug162011

Methane

"It's meth-ane, not 'me'-thane. It is the smallest hydrocarbon and the lightest stable organic molecule. A methane molecule has a regular tetrahedral structure (Td symmetry), its H-C-H angles are all 109½°"

"Methane is a colorless, odorless gas with a wide distribution in nature. It is the principal component of natural gas, a mixture containing about 75% CH4, 15% ethane (C2H6), and 5% other hydrocarbons, such as propane (C3H8) and butane (C4H10). The "firedamp" of coal mines is chiefly methane. Anaerobic bacterial decomposition of plant and animal matter, such as occurs under water, produces marsh gas, which is also methane."

Monday
Aug152011

Heavy Water, D2O

"Francis Aston (photo, right) found evidence for the existence of isotopes in 1913, and he published his findings in 1920. Aston was awarded the Nobel prize for Chemistry in 1922. Soon after, Rutherford suggested the existence of a heavier isotope of hydrogen, which we now call deuterium. It was first detected in 1931 by Harold Clayton Urey (see photo, below), who found that he could enrich liquid hydrogen somewhat by fractional distillation, and confirmed the cause of weak lines in the atomic spectrum of samples of hydrogen as due to the presence of small amounts of deuterium. Using electrolysis, Urey succeeded in enriching samples of water in the heavier isotope. The next step was to isolate pure heavy water. Along with his student Ronald T. MacDonald, the great American chemist Gilbert Newton Lewis (1875-1946) set to the task, using both electrolysis and fractional distillation under reduced pressure (employing a 72-feet-high distillation column). Armed with his supply of deuterium oxide, Lewis set out to investigate its properties - not just the obvious ones, like melting and boiling points - but also whether it would support life (a white mouse drank it and came back for more)."

Sunday
Aug142011

Kevlar

"Kevlar is well known as the material from which bullet-proof vests and body armour is made. But it can be used in many more applications, such as bicycle tyres, yacht sails, ropes, and brakepads. It can do this because, despite it being a fibre, it has an extremely high stength-to-weight ratio, often qiuoted as being 5 times stronger than an equal weight of steel. It is actually a trademark of the chemical company DuPont, who first synthesised it in 1965."