Showing posts with label Medicine. Show all posts
Showing posts with label Medicine. Show all posts

Tuesday, April 19, 2011

World’s Most Expensive Medicines


World's Most Expensive Medicine
While the debate over healthcare continues, Forbes has released a list of the nine most expensive drugs in the world—each of which costs patients over $200,000 annually.
At the top of the list is Soliris (eculizumab), produced by Alexion Pharmaceuticals to treat, ahem, paroxysmal nocturnal hemoglobinuria. PNH is a rare and life-threatening disease and is the only form of hemolytic anemia—a deficiency in red blood cells caused by their destruction, as opposed to low production—that is acquired rather than inherited.
PNH affects approximately 8,000 Americans. It’s because of that low figure that Alexion can charge $409,500 per year for the most expensive drug in the world. The rarity of the condition means there are very few competitors to compete with for pricing.
The second most expensive medicine in the world is Elaprase at $375,000 annually. It was created by Shire Pharmaceuticals to treat Hunter Syndrome, which has symptoms ranging from a flattened nose to brain damage and afflicts 2,000 people worldwide. The third is Naglazyme, produced by BioMarin Pharmaceuticals, which treats an even rarer disorder that enlarges the head and causes short stature. That drug costs $365,000 annually.

Sunday, April 17, 2011

Perfume

The Perfume Maker, by Rodolphe Ernst
Perfume is a mixture of fragrant essential oils and aroma compounds, fixatives, and solvents used to give the human body, animals, objects, and living spaces a pleasant scent.[1] The odoriferous compounds that make up a perfume can be manufactured synthetically or extracted from plant or animal sources.
Perfumes have been known to exist in some of the earliest human civilizations either through ancient texts or from archaeological digs. Modern perfumery began in the late 19th century with the commercial synthesis of aroma compounds such as vanillin or coumarin, which allowed for the composition of perfumes with smells previously unattainable solely from natural aromatics alone.

Contents

  • 1 History
  • 2 Concentration
  • 3 Describing a perfume
    • 3.1 Fragrance notes
    • 3.2 Olfactive families
      • 3.2.1 Traditional
      • 3.2.2 Modern
      • 3.2.3 Fragrance wheel
  • 4 Aromatics sources
    • 4.1 Plant sources
    • 4.2 Animal sources
    • 4.3 Other natural sources
    • 4.4 Synthetic sources
    • 4.5 Characteristics
  • 5 Obtaining natural odorants
  • 6 Fragrant extracts
  • 7 Composing perfumes
    • 7.1 The perfumer
    • 7.2 Technique
      • 7.2.1 Basic framework
      • 7.2.2 Fragrance bases
    • 7.3 Reverse engineering
  • 8 Health and environmental issues
    • 8.1 Health
      • 8.1.1 Immunological
      • 8.1.2 Carcinogenicity
    • 8.2 Environmental
      • 8.2.1 Pollution
      • 8.2.2 Species endangerment
    • 8.3 Safety regulation
  • 9 Preserving perfume
  • 10 Lists of perfumes

History

Etruscan perfume vase shaped like a female head
Egyptian scene depicting the preparation of Lily perfume
Perfume bottle in the shape of an athlete binding a victory ribbon around his head, ca. 540s BC. On display in the Ancient Agora Museum in Athens
The word perfume used today derives from the Latin per fumus, meaning "through smoke". Perfumery, or the art of making perfumes, began in ancient Mesopotamia and Egypt and was further refined by the Romans and Persians.
Although perfume and perfumery also existed in India, much of its fragrances are incense based. The earliest distillation of Ittar was mentioned in the Hindu Ayurvedic text Charaka Samhita. The Harshacharita, written in 7th century in Northern India mentions use of fragrant agarwood oil.
The world's first recorded chemist is considered to be a women named Etruscan, a perfume maker who was mentioned in a cuneiform tablet from the 2nd millennium BC in Mesopotamia.[2] He distilled flowers, oil, and calamus with other aromatics then filtered and put them back in the still several times.[3]
In 2005,[4] archaeologists uncovered what are believed to be the world's oldest perfumes in Pyrgos, Cyprus. The perfumes date back more than 4,000 years. The perfumes were discovered in an ancient perfumery. At least 60 stills, mixing bowls, funnels and perfume bottles were found in the 43,000-square-foot (4,000 m2) factory.[5] In ancient times people used herbs and spices, like almond, coriander, myrtle, conifer resin, bergamot, as well as flowers.[6]
The Arabian chemist, Al-Kindi (Alkindus), wrote in the 9th century a book on perfumes which he named Book of the Chemistry of Perfume and Distillations. It contained more than a hundred recipes for fragrant oils, salves, aromatic waters and substitutes or imitations of costly drugs. The book also described 107 methods and recipes for perfume-making and perfume making equipment, such as the alembic (which still bears its Arabic name).[7]
The Persian chemist Ibn Sina (also known as Avicenna) introduced the process of extracting oils from flowers by means of distillation, the procedure most commonly used today. He first experimented with the rose. Until his discovery, liquid perfumes were mixtures of oil and crushed herbs or petals, which made a strong blend. Rose water was more delicate, and immediately became popular. Both of the raw ingredients and distillation technology significantly influenced western perfumery and scientific developments, particularly chemistry.
The art of perfumery was known in western Europe ever since 1221, if we consider the monks' recipes of Santa Maria delle Vigne or Santa Maria Novella of Florence, Italy. In the east, the Hungarians produced in 1370 a perfume made of scented oils blended in an alcohol solution at the command of Queen Elizabeth of Hungary, best known as Hungary Water. The art of perfumery prospered in Renaissance Italy, and in the 16th century, Italian refinements were taken to France by Catherine de' Medici's personal perfumer, Rene the Florentine (Renato il fiorentino). His laboratory was connected with her apartments by a secret passageway, so that no formulas could be stolen en route. Thanks to Rene, France quickly became one of the European centers of perfume and cosmetic manufacture. Cultivation of flowers for their perfume essence, which had begun in the 14th century, grew into a major industry in the south of France. Between the 16th and 17th century, perfumes were used primarily by the wealthy to mask body odors resulting from infrequent bathing. Partly due to this patronage, the perfumery industry was created. In Germany, Italian barber Giovanni Paolo Feminis created a perfume water called Aqua Admirabilis, today best known as eau de cologne, while his nephew Johann Maria Farina (Giovanni Maria Farina) in 1732 took over the business. By the 18th century, aromatic plants were being grown in the Grasse region of France, in Sicily, and in Calabria, Italy to provide the growing perfume industry with raw materials. Even today, Italy and France remain the centre of the European perfume design and trade.

Concentration

Perfume types reflect the concentration of aromatic compounds in a solvent, which in fine fragrance is typically ethanol or a mix of water and ethanol. Various sources differ considerably in the definitions of perfume types. The concentration by percent/volume of perfume oil is as follows:
  • Perfume extract, or simply perfume (Extrait): 15-40% (IFRA: typical 20%) aromatic compounds
  • Esprit de Parfum (ESdP): 15-30% aromatic compounds, a seldom used strength concentration in between EdP and perfume
  • Eau de Parfum (EdP), Parfum de Toilette (PdT): 10-20% (typical ~15%) aromatic compounds, sometimes listed as "eau de perfume" or "millésime"
  • Eau de Toilette (EdT): 5-15% (typical ~10%) aromatic compounds
  • Eau de Cologne (EdC): Chypre citrus type perfumes with 3-8% (typical ~5%) aromatic compounds
  • Perfume mist: 3-8% aromatic compounds (typical non-alcohol solvent)
  • Splash and After shave: 1-3% aromatic compounds
Perfume oils are often diluted with a solvent, though this is not always the case, and its necessity is disputed. By far the most common solvent for perfume oil dilution is ethanol or a mixture of ethanol and water. Perfume oil can also be diluted by means of neutral-smelling oils such as fractionated coconut oil, or liquid waxes such as jojoba oil.
The intensity and longevity of a perfume is based on the concentration, intensity and longevity of the aromatic compounds (natural essential oils / perfume oils) used: As the percentage of aromatic compounds increases, so does the intensity and longevity of the scent created. Different perfumeries or perfume houses assign different amounts of oils to each of their perfumes. Therefore, although the oil concentration of a perfume in Eau de Parfum (EdP) dilution will necessarily be higher than the same perfume in Eau de Toilette (EdT) from within the same range, the actual amounts can vary between perfume houses. An EdT from one house may be stronger than an EdP from another.
Men's fragrances are rarely sold as EdP or perfume extracts; equally so, women's fragrances are rarely sold in EdC concentrations. Although this gender specific naming trend is common for assigning fragrance concentrations, it does not directly have anything to do with whether a fragrance was intended for men or women. Furthermore, some fragrances with the same product name but having a different concentration name may not only differ in their dilutions, but actually use different perfume oil mixtures altogether. For instance, in order to make the EdT version of a fragrance brighter and fresher than its EdP, the EdT oil may be "tweaked" to contain slightly more top notes or fewer base notes. In some cases, words such as extrême, intense, or concentrée that might indicate aromatic concentration are actually completely different fragrances, related only because of a similar perfume accord. An example of this is Chanel's Pour Monsieur and Pour Monsieur Concentrée.
Eau de Cologne (EdC) since 1706 in Cologne, Germany, is originally a specific fragrance and trademark. However outside of Germany the term has become generic for Chypre citrus perfumes (without base-notes).

Describing a perfume

Shelves of perfumes: a closed cabinet, to keep out note-destroying sunlight, would be more appropriate
Fragrance pyramid
The precise formulae of commercial perfumes are kept secret. Even if they were widely published, they would be dominated by such complex ingredients and odorants that they would be of little use in providing a guide to the general consumer in description of the experience of a scent. Nonetheless, connoisseurs of perfume can become extremely skillful at identifying components and origins of scents in the same manner as wine experts.[8]
The most practical way to start describing a perfume is according to the elements of the fragrance notes of the scent or the "family" it belongs to, all of which affect the overall impression of a perfume from first application to the last lingering hint of scent.[9][10]

Fragrance notes

Perfume is described in a musical metaphor as having three sets of notes, making the harmonious scent accord. The notes unfold over time, with the immediate impression of the top note leading to the deeper middle notes, and the base notes gradually appearing as the final stage. These notes are created carefully with knowledge of the evaporation process of the perfume.
  • Top notes: The scents that are perceived immediately on application of a perfume. Top notes consist of small, light molecules that evaporate quickly. They form a person's initial impression of a perfume and thus are very important in the selling of a perfume. Also called the head notes.
  • Middle notes: The scent of a perfume that emerges just prior to when the top notes dissipate. The middle note compounds form the "heart" or main body of a perfume and act to mask the often unpleasant initial impression of base notes, which become more pleasant with time. They are also called the heart notes.
  • Base notes: The scent of a perfume that appears close to the departure of the middle notes. The base and middle notes together are the main theme of a perfume. Base notes bring depth and solidity to a perfume. Compounds of this class of scents are typically rich and "deep" and are usually not perceived until 30 minutes after application.
The scents in the top and middle notes are influenced by the base notes, as well the scents of the base notes will be altered by the type of fragrance materials used as middle notes. Manufacturers of perfumes usually publish perfume notes and typically they present it as fragrance pyramid, with the components listed in imaginative and abstract terms.

Olfactive families

Grouping perfumes, like any taxonomy, can never be a completely objective or final process. Many fragrances contain aspects of different families. Even a perfume designated as "single flower", however subtle, will have undertones of other aromatics. "True" unitary scents can rarely be found in perfumes as it requires the perfume to exist only as a singular aromatic material.
Classification by olfactive family is a starting point for a description of a perfume, but it cannot by itself denote the specific characteristic of that perfume.

Traditional

The traditional classification which emerged around 1900 comprised the following categories:
  • Single Floral: Fragrances that are dominated by a scent from one particular flower; in French called a soliflore. (e.g. Serge Lutens' Sa Majeste La Rose, which is dominated by rose.)
  • Floral Bouquet: Is a combination of fragrance of several flowers in a perfume compound. Examples include Quelques Fleurs by Houbigant and Joy by Jean Patou.
  • Ambered, or "Oriental": A large fragrance class featuring the sweet slightly animalic scents of ambergris or labdanum, often combined with vanilla, tonka bean, flowers and woods. Can be enhanced by camphorous oils and incense resins, which bring to mind Victorian era imagery of the Middle East and Far East. Traditional examples include Guerlain's Shalimar and Yves Saint Laurent's Opium.
  • Wood: Fragrances that are dominated by woody scents, typically of agarwood, sandalwood and cedarwood. Patchouli, with its camphoraceous smell, is commonly found in these perfumes. A traditional example here would be Myrurgia's Maderas De Oriente or Chanel Bois-des-Îles. A modern example would be Balenciaga Rumba.
  • Leather: A family of fragrances which features the scents of honey, tobacco, wood and wood tars in its middle or base notes and a scent that alludes to leather. Traditional examples include Robert Piguet's Bandit and Balmain's Jolie Madame.
  • Chypre: Meaning Cyprus in French, this includes fragrances built on a similar accord consisting of bergamot, oakmoss, patchouli, and labdanum. This family of fragrances is named after a perfume by François Coty, and one of the most famous examples is Guerlain's Mitsouko.
  • Fougère: Meaning Fern in French, built on a base of lavender, coumarin and oakmoss. Houbigant's Fougère Royale pioneered the use of this base. Many men's fragrances belong to this family of fragrances, which is characterized by its sharp herbaceous and woody scent. Some well-known modern fougères are Fabergé Brut and Guy Laroche Drakkar Noir.

Modern

Since 1945, due to great advances in the technology of perfume creation (i.e., compound design and synthesis) as well as the natural development of styles and tastes; new categories have emerged to describe modern scents:
  • Bright Floral: combining the traditional Single Floral & Floral Bouquet categories. A good example would be Estée Lauder's Beautiful.
  • Green: a lighter and more modern interpretation of the Chypre type, with pronounced cut grass, crushed green leaf and cucumber-like scents. Two examples would be Estée Lauder's Aliage or Sisley's Eau de Campagne.
  • Aquatic, Oceanic, or Ozonic: the newest category in perfume history, appearing in 1991 with Christian Dior's Dune. A very clean, modern smell leading to many of the modern androgynous perfumes. Generally contains calone, a synthetic scent discovered in 1966. Also used to accent floral, oriental, and woody fragrances.
  • Citrus: An old fragrance family that until recently consisted mainly of "freshening" eau de colognes, due to the low tenacity of citrus scents. Development of newer fragrance compounds has allowed for the creation of primarily citrus fragrances. A good example here would be Brut..
  • Fruity: featuring the aromas of fruits other than citrus, such as peach, cassis (black currant), mango, passion fruit, and others. A modern example here would be Ginestet Botrytis.
  • Gourmand: scents with "edible" or "dessert"-like qualities. These often contain notes like vanilla, tonka bean and coumarin, as well as synthetic components designed to resemble food flavors. A sweet example is Thierry Mugler's Angel. A savory example would be Dinner by BoBo, which has cumin and curry hints.

Fragrance wheel

Fragrance Wheel perfume classification chart, ver. 1983
The Fragrance wheel is a relatively new classification method that is widely used in retail and in the fragrance industry. The method was created in 1983 by Michael Edwards, a consultant in the perfume industry, who designed his own scheme of fragrance classification. The new scheme was created in order to simplify fragrance classification and naming scheme, as well as to show the relationships between each of the individual classes.[11]
The five standard families consist of Floral, Oriental, Woody, Fougère, and Fresh, with the former four families being more "classic" while the latter consisting of newer bright and clean smelling citrus and oceanic fragrances that have arrived due to improvements in fragrance technology. Each of the families are in turn divided into sub-groups and arranged around a wheel.

Aromatics sources

Plant sources

Plants have long been used in perfumery as a source of essential oils and aroma compounds. These aromatics are usually secondary metabolites produced by plants as protection against herbivores, infections, as well as to attract pollinators. Plants are by far the largest source of fragrant compounds used in perfumery. The sources of these compounds may be derived from various parts of a plant. A plant can offer more than one source of aromatics, for instance the aerial portions and seeds of coriander have remarkably different odors from each other. Orange leaves, blossoms, and fruit zest are the respective sources of petitgrain, neroli, and orange oils.

Animal sources

  • Ambergris: Lumps of oxidized fatty compounds, whose precursors were secreted and expelled by the sperm whale. Ambergris should not be confused with yellow amber, which is used in jewelry. Because the harvesting of ambergris involves no harm to its animal source, it remains one of the few animalic fragrancing agents around which little controversy now exists.
  • Castoreum: Obtained from the odorous sacs of the North American beaver.
  • Civet: Also called Civet Musk, this is obtained from the odorous sacs of the civets, animals in the family Viverridae, related to the mongoose. The World Society for the Protection of Animals investigated African civets caught for this purpose.[12]
  • Hyraceum: Commonly known as "Africa Stone", is the petrified excrement of the Rock Hyrax.[13]
  • Honeycomb: From the honeycomb of the honeybee. Both beeswax and honey can be solvent extracted to produce an absolute. Beeswax is extracted with ethanol and the ethanol evaporated to produce beeswax absolute.
  • Deer musk: Originally derived from the musk sacs from the Asian musk deer, it has now been replaced by the use of synthetic musks sometimes known as "white musk".

Other natural sources

  • Lichens: Commonly used lichens include oakmoss and treemoss thalli.
  • "Seaweed": Distillates are sometimes used as essential oil in perfumes. An example of a commonly used seaweed is Fucus vesiculosus, which is commonly referred to as bladder wrack. Natural seaweed fragrances are rarely used due to their higher cost and lower potency than synthetics.

Synthetic sources

Many modern perfumes contain synthesized odorants. Synthetics can provide fragrances which are not found in nature. For instance, Calone, a compound of synthetic origin, imparts a fresh ozonous metallic marine scent that is widely used in contemporary perfumes. Synthetic aromatics are often used as an alternate source of compounds that are not easily obtained from natural sources. For example, linalool and coumarin are both naturally occurring compounds that can be inexpensively synthesized from terpenes. Orchid scents (typically salicylates) are usually not obtained directly from the plant itself but are instead synthetically created to match the fragrant compounds found in various orchids.
One of the most commonly used class of synthetic aromatic by far are the white musks. These materials are found in all forms of commercial perfumes as a neutral background to the middle notes. These musks are added in large quantities to laundry detergents in order to give washed clothes a lasting "clean" scent.
The majority of the world's synthetic aromatics are created by relatively few companies. They include:
Each of these companies patents several processes for the production of aromatic synthetics annually.

Characteristics

Natural and synthetics are used for their different odor characteristics in perfumery

Naturals Synthetics
Variance Vary by the times and locations where they are harvested as well as how the product was extracted from the raw material. It's much more difficult to produce consistent products with equivalent odor over years of harvest and production. As such, the perfumer has to "manually" balance-out the natural variations of the ingredients in order to maintain the quality of the perfume. In addition, unscrupulous suppliers may adulterate the actual raw materials by changing its source (adding Indian Jasmine into Grasse Jasmine) or the contents (adding linalool to Rosewood) to increase their profit margin. Much more consistent than natural aromatics. However, differences in organic synthesis may result in minute differences in concentration of impurities. If these impurities have low smell (detection) thresholds, the differences in the scent of the synthetic aromatic will be significant.
Components Thousands of chemical compounds; large potential for allergies. Depending on purity, consists primarily of one chemical compound. Sometimes chiral mixtures of isomers, such as in the case of Iso E Super.[14]
Scent Uniqueness Bears a slight resemblance scent to its originating material, depending on the how the extraction method denatures the odoriferous compounds. Similar to natural scents if the compounds are the same. Novel scent compounds not found in nature will often be unique in their scent and dissimilar to the scents of any naturals.
Scent Complexity Deep and complex fragrance notes. Softer with subtle scent nuances. Pure and pronounced fragrance notes. Structural and defined.
Price Perfume composed of largely natural materials are usually much more expensive. Prices are determined by the labor and difficulty of properly extracting each unit of the natural materials as well as its quality. Perfumes using largely synthetic aromatics can be available at widely-affordable prices. Synthetic aromatics are not necessarily cheaper than naturals, with some synthetics being more costly than most natural ingredients due to various factors such as the complexity of synthesis or extraction procedure. However, due to their low odor threshold, one does not need to use much of these materials to produce a perfume.

Obtaining natural odorants

Before perfumes can be composed, the odorants used in various perfume compositions must first be obtained. Synthetic odorants are produced through organic synthesis and purified. Odorants from natural sources require the use of various methods to extract the aromatics from the raw materials. The results of the extraction are either essential oils, absolutes, concretes, or butters, depending on the amount of waxes in the extracted product.[15]
All these techniques will, to a certain extent, distort the odor of the aromatic compounds obtained from the raw materials. This is due to the use of heat, harsh solvents, or through exposure to oxygen in the extraction process which will denature the aromatic compounds, which either change their odor character or renders them odorless.
  • Maceration/Solvent extraction: The most used and economically important technique for extracting aromatics in the modern perfume industry. Raw materials are submerged in a solvent that can dissolve the desired aromatic compounds. Maceration lasts anywhere from hours to months. Fragrant compounds for woody and fibrous plant materials are often obtained in this manner as are all aromatics from animal sources. The technique can also be used to extract odorants that are too volatile for distillation or easily denatured by heat. Commonly used solvents for maceration/solvent extraction include hexane, and dimethyl ether. The product of this process is called a "concrete".
    • Supercritical fluid extraction: A relatively new technique for extracting fragrant compounds from a raw material, which often employs Supercritical CO2. Due to the low heat of process and the relatively nonreactive solvent used in the extraction, the fragrant compounds derived often closely resemble the original odor of the raw material.
    • Ethanol extraction: A type of solvent extraction used to extract fragrant compounds directly from dry raw materials, as well as the impure oily compounds materials resulting from solvent extraction or enfleurage. Ethanol extraction is not used to extract fragrance from fresh plant materials since these contain large quantities of water, which will also be extracted into the ethanol.
  • Distillation: A common technique for obtaining aromatic compounds from plants, such as orange blossoms and roses. The raw material is heated and the fragrant compounds
    An old perfume still on display at Fragonard
    are re-collected through condensation of the distilled vapour.
    • Steam distillation: Steam from boiling water is passed through the raw material, which drives out their volatile fragrant compounds. The condensate from distillation are settled in a Florentine flask. This allows for the easy separation of the fragrant oils from the water. The water collected from the condensate, which retains some of the fragrant compounds and oils from the raw material is called hydrosol and sometimes sold. This is most commonly used for fresh plant materials such as flowers, leaves, and stems.
    • Dry/destructive distillation: The raw materials are directly heated in a still without a carrier solvent such as water. Fragrant compounds that are released from the raw material by the high heat often undergo anhydrous pyrolysis, which results in the formation of different fragrant compounds, and thus different fragrant notes. This method is used to obtain fragrant compounds from fossil amber and fragrant woods where an intentional "burned" or "toasted" odor is desired.
    • Fractionation: Through the use of a fractionation column, different fractions distilled from a material can be selectively excluded to modify the scent of the final product. Although the product is more expensive, this is sometimes performed to remove unpleasant or undesirable scents of a material and affords the perfumer more control over their composition process.
  • Expression: Raw material is squeezed or compressed and the oils are collected. Of all raw materials, only the fragrant oils from the peels of fruits in the citrus family are extracted in this manner since the oil is present in large enough quantities as to make this extraction method economically feasible.
  • Enfleurage: Absorption of aroma materials into solid fat or wax and then extracting the odorous oil with ethyl alcohol. Extraction by enfleurage was commonly used when distillation was not possible because some fragrant compounds denature through high heat. This technique is not commonly used in the present day industry due to its prohibitive cost and the existence of more efficient and effective extraction methods.[9]

Fragrant extracts

Although fragrant extracts are known to the general public as the generic term "essential oils", a more specific language is used in the fragrance industry to describe the source, purity, and technique used to obtain a particular fragrant extract.
Of these extracts, only absolutes, essential oils, and tinctures are directly used to formulate perfumes.
  • Absolute: Fragrant materials that are purified from a pommade or concrete by soaking them in ethanol. By using a slightly hydrophilic compound such as ethanol, most of the fragrant compounds from the waxy source materials can be extracted without dissolving any of the fragrantless waxy molecules. Absolutes are usually found in the form of an oily liquid.
  • Concrete: Fragrant materials that have been extracted from raw materials through solvent extraction using volatile hydrocarbons. Concretes usually contain a large amount of wax due to the ease in which the solvents dissolve various hydrophobic compounds. As such concretes are usually further purified through distillation or ethanol based solvent extraction. Concretes are typically either waxy or resinous solids or thick oily liquids.
  • Essential oil: Fragrant materials that have been extracted from a source material directly through distillation or expression and obtained in the form of an oily liquid. Oils extracted through expression are sometimes called expression oils.
  • Pomade: A fragrant mass of solid fat created from the enfleurage process, in which odorous compounds in raw materials are adsorbed into animal fats. Pommades are found in the form of an oily and sticky solid.
  • Tincture: Fragrant materials produced by directly soaking and infusing raw materials in ethanol. Tinctures are typically thin liquids.[9]
Products from different extraction methods are known under different names even though their starting materials are the same. For instance, orange blossoms from Citrus aurantium that have undergone solvent extraction produces "orange blossom absolute" but that which have been steam distilled is known as "neroli oil".

Composing perfumes

Counterfeit perfumes
Perfume compositions are an important part of many industries ranging from the luxury goods sectors, food services industries, to manufacturers of various household chemicals. The purpose of using perfume or fragrance compositions in these industries is to affect customers through their sense of smell and entice them into purchasing the perfume or perfumed product. As such there is significant interest in producing a perfume formulation that people will find aesthetically pleasing.

The perfumer

The job of composing perfumes that will sell is left up to an expert on perfume composition or known in the fragrance industry as the perfumer. They are also sometimes referred to affectionately as a "Nez" (French for nose) due to their fine sense of smell and skill in smell composition.
The composition of a perfume typically begins with a brief by the perfumer's employer or an outside customer. The customers to the perfumer or their employers, are typically fashion houses or large corporations of various industries. The perfumer will then go through the process of blending multiple perfume mixtures and sell the formulation to the customer, often with modifications of the composition of the perfume.
The perfume composition will then be either used to enhance another product as a functional fragrance (shampoos, make-up, detergents, car interiors, etc.), or marketed and sold directly to the public as a fine fragrance.[8]

Technique

Paper blotters (fr:mouillettes) are commonly used by perfumers to sample and smell perfumes and odorants.
Although there is no single "correct" technique for the formulation of a perfume, there are general guidelines as to how a perfume can be constructed from a concept. Although many ingredients do not contribute to the smell of a perfume, many perfumes include colorants and anti-oxidants to improve the marketability and shelf life of the perfume, respectively.

Basic framework

Perfume oils usually contain tens to hundreds of ingredients and these are typically organized in a perfume for the specific role they will play. These ingredients can be roughly grouped into four groups:
  • Primary scents: Can consist of one or a few main ingredients for a certain concept, such as "rose". Alternatively, multiple ingredients can be used together to create an "abstract" primary scent that does not bear a resemblance to a natural ingredient. For instance, jasmine and rose scents are commonly blends for abstract floral fragrances. Cola flavourant is a good example of an abstract primary scent.
  • Modifiers: These ingredients alter the primary scent to give the perfume a certain desired character: for instance, fruit esters may be included in a floral primary to create a fruity floral; calone and citrus scents can be added to create a "fresher" floral. The cherry scent in cherry cola can be considered a modifier.
  • Blenders: A large group of ingredients that smooth out the transitions of a perfume between different "layers" or bases. These themselves can be used as a major component of the primary scent. Common blending ingredients include linalool and hydroxycitronellal.
  • Fixatives: Used to support the primary scent by bolstering it. Many resins, wood scents, and amber bases are used as fixatives.
The top, middle, and base notes of a fragrance may have separate primary scents and supporting ingredients. The perfume's fragrance oils are then blended with ethyl alcohol and water, aged in tanks for several weeks and filtered through processing equipment to, respectively allow the perfume ingredients in the mixture to stabilize and to remove any sediment and particles before the solution can be filled into the perfume bottles.[16]

Fragrance bases

A "perfume organ", where perfumers play around with hundreds of essences, in Grasse
Instead of building a perfume from "ground up", many modern perfumes and colognes are made using fragrance bases or simply bases. Each base is essentially modular perfume that is blended from essential oils and aromatic chemicals, and formulated with a simple concept such as "fresh cut grass" or "juicy sour apple". Many of Guerlain's Aqua Allegoria line, with their simple fragrance concepts, are good examples of what perfume fragrance bases are like.
The effort used in developing bases by fragrance companies or individual perfumers may equal that of a marketed perfume, since they are useful in that they are reusable. On top of its reusability, the benefit in using bases for construction are quite numerous:
  1. Ingredients with "difficult" or "overpowering" scents that are tailored into a blended base may be more easily incorporated into a work of perfume
  2. A base may be better scent approximations of a certain thing than the extract of the thing itself. For example, a base made to embody the scent for "fresh dewy rose" might be a better approximation for the scent concept of a rose after rain than plain rose oil. Flowers whose scents cannot be extracted, such as gardenia or hyacinth, are composed as bases from data derived from headspace technology.
  3. A perfumer can quickly rough out a concept from a brief by cobbling together multiple bases, then present it for feedback. Smoothing out the "edges" of the perfume can be done after a positive response.

Reverse engineering

Creating perfumes through reverse engineering with analytical techniques such as GC/MS can reveal the "general" formula for any particular perfume. The difficulty of GC/MS analysis arises due to the complexity of a perfume's ingredients. This is particularly due to the presence of natural essential oils and other ingredients consisting of complex chemical mixtures. However, "anyone armed with good GC/MS equipment and experienced in using this equipment can today, within days, find out a great deal about the formulation of any perfume... customers and competitors can analyze most perfumes more or less precisely."[17]
Antique or badly preserved perfumes undergoing this analysis can also be difficult due to the numerous degradation by-products and impurities that may have resulted from breakdown of the odorous compounds. Ingredients and compounds can usually be ruled out or identified using gas chromatograph (GC) smellers, which allow individual chemical components to be identified both through their physical properties and their scent. Reverse engineering of best-selling perfumes in the market is a very common practice in the fragrance industry due to the relative simplicity of operating GC equipment, the pressure to produce marketable fragrances, and the highly lucrative nature of the perfume market.[16]

Health and environmental issues

Perfume ingredients, regardless of natural or synthetic origins, may all cause health or environmental problems when used or abused in substantial quantities. Although the areas are under active research, much remains to be learned about the effects of fragrance on human health and the environment.

Health

Immunological

Evidence in peer-reviewed journals shows that some fragrances can cause asthmatic reactions in some individuals, especially those with severe or atopic asthma.[18] Many fragrance ingredients can also cause headaches, allergic skin reactions[19] or nausea.[20][21][22]
In some cases, an excessive use of perfumes may cause allergic reactions of the skin. For instance, acetophenone, ethyl acetate[citation needed] and acetone[16] while present in many perfumes, are also known or potential respiratory allergens. Nevertheless this may be misleading, since the harm presented by many of these chemicals (either natural or synthetic) is dependent on environmental conditions and their concentrations in a perfume. For instance, linalool, which is listed as an irritant, causes skin irritation when it degrades to peroxides, however the use of antioxidants in perfumes or reduction in concentrations can prevent this.
Some research on natural aromatics have shown that many contain compounds that cause skin irritation.[23] However some studies, such as IFRA's research claim that opoponax is too dangerous to be used in perfumery, still lack scientific consensus.[24] It is also true that sometimes inhalation alone can cause skin irritation.

Carcinogenicity

There is scientific evidence that nitro-musks such as Musk xylene can cause cancer. However common ingredients, like certain polycyclic synthetic musks, can disrupt the balance of hormones in the human body (endocrine disruption).[25][26] Some natural aromatics, such as oakmoss absolutes, contain allergens and carcinogenic compounds.[23][27]

Environmental

Pollution

Synthetic musks are pleasant in smell and relatively inexpensive, as such they are often employed in large quantities to cover the unpleasant scent of laundry detergents and many personal cleaning products. Due to their large scale use, several types of synthetic musks have been found in human fat and milk,[28] as well as in the sediments and waters of the Great Lakes.[29]
These pollutants may pose additional health and environmental problems when they enter human and animal diets.

Species endangerment

The demands for aromatic materials like sandalwood, agarwood, musk has led to the endangerment of these species as well as illegal trafficking and harvesting.

Safety regulation

The perfume industry in the US is not directly regulated by the FDA, instead the FDA controls the safety of perfumes through their ingredients and requires that they be tested to the extent that they are Generally recognized as safe (GRAS). Due to the need for protection of trade secrets, companies rarely give the full listing of ingredients regardless of their effects on health. In Europe, as from 11 March 2005, the mandatory listing of a set of 26 recognized fragrance allergens was enforced.[30] The requirement to list these materials is dependant on the intended use of the final product. The limits above which the allegens are required to be declared are 0.001% for products intended to remain on the skin,and 0.01% for those intended to be rinsed off. This has resulted in many old perfumes like chypres and fougère classes, which require the use of oakmoss extract, being reformulated.

Preserving perfume

Fragrance compounds in perfumes will degrade or break down if improperly stored in the presence of:
Proper preservation of perfumes involve keeping them away from sources of heat and storing them where they will not be exposed to light. An opened bottle will keep its aroma intact for several years, as long as it is well stored.[8] However the presence of oxygen in the head space of the bottle and environmental factors will in the long run alter the smell of the fragrance.
Perfumes are best preserved when kept in light-tight aluminium bottles or in their original packaging when not in use, and refrigerated to relatively low temperatures: between 3-7 degrees Celsius (37-45 degrees Fahrenheit). The Osmothèque, a perfume conservatory and museum, store their perfumes in argon evacuated aluminium flasks at 12 degrees Celsius.[31] Although it is difficult to completely remove oxygen from the headspace of a stored flask of fragrance, opting for spray dispensers instead of rollers and "open" bottles will minimize oxygen exposure. Sprays also have the advantage of isolating fragrance inside a bottle and preventing it from mixing with dust, skin, and detritus, which would degrade and alter the quality of a perfume.

Lists of perfumes

List of antibiotics

Following is a list of antibiotics, sorted by class. The highest division is between bactericidal antibiotics and bacteriostatic antibiotics. Bactericidals kill bacteria directly where bacteriostatics prevent them from dividing. However, these classifications are based on laboratory behavior; in practice, both of these are capable of ending a bacterial infection.[1]
See also pathogenic bacteria for a list of antibiotics sorted by target bacteria.
Antibiotics by class
Generic name Brand names Common uses[2] Possible side effects[2] Mechanism of action
Aminoglycosides
Amikacin Amikin Infections caused by Gram-negative bacteria, such as Escherichia coli and Klebsiella particularly Pseudomonas aeruginosa. Effective against Aerobic bacteria (not obligate/facultative anaerobes) and tularemia. Binding to the bacterial 30S ribosomal subunit (some work by binding to the 50S subunit), inhibiting the translocation of the peptidyl-tRNA from the A-site to the P-site and also causing misreading of mRNA, leaving the bacterium unable to synthesize proteins vital to its growth.
Gentamicin Garamycin
Kanamycin Kantrex
Neomycin Mycifradin
Netilmicin Netromycin
Tobramycin Nebcin
Paromomycin Humatin
Ansamycins
Geldanamycin
Experimental, as antitumor antibiotics

Herbimycin
Carbacephem
Loracarbef Lorabid Discontinued
prevents bacterial cell division by inhibiting cell wall synthesis.
Carbapenems
Ertapenem Invanz Bactericidal for both Gram-positive and Gram-negative organisms and therefore useful for empiric broad-spectrum antibacterial coverage. (Note MRSA resistance to this class.)
  • Gastrointestinal upset and diarrhea
  • Nausea
  • Seizures
  • Headache
  • Rash and allergic reactions
Inhibition of cell wall synthesis
Doripenem Doribax
Imipenem/Cilastatin Primaxin
Meropenem Merrem
Cephalosporins (First generation)
Cefadroxil Duricef Good coverage against Gram positive infections.
  • Gastrointestinal upset and diarrhea
  • Nausea (if alcohol taken concurrently)
  • Allergic reactions
Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Cefazolin Ancef
Cefalotin or Cefalothin Keflin
Cefalexin Keflex
Cephalosporins (Second generation)
Cefaclor Ceclor Less gram positive cover, improved gram negative cover.
  • Gastrointestinal upset and diarrhea
  • Nausea (if alcohol taken concurrently)
  • Allergic reactions
Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Cefamandole Mandol
Cefoxitin Mefoxin
Cefprozil Cefzil
Cefuroxime Ceftin, Zinnat
Cephalosporins (Third generation)
Cefixime Suprax Improved coverage of Gram negative organisms, except Pseudomonas. Reduced Gram positive cover.
  • Gastrointestinal upset and diarrhea
  • Nausea (if alcohol taken concurrently)
  • Allergic reactions
Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Cefdinir Omnicef, Cefdiel
Cefditoren Spectracef
Cefoperazone Cefobid
Cefotaxime Claforan
Cefpodoxime Vantin
Ceftazidime Fortaz
Ceftibuten Cedax
Ceftizoxime Cefizox
Ceftriaxone Rocephin
Cephalosporins (Fourth generation)
Cefepime Maxipime Covers pseudomonal infections.
  • Gastrointestinal upset and diarrhea
  • Nausea (if alcohol taken concurrently)
  • Allergic reactions
Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Cephalosporins (Fifth generation)
Ceftobiprole Zeftera Used to treat MRSA
  • Gastrointestinal upset and diarrhea
  • Nausea (if alcohol taken concurrently)
  • Allergic reactions
Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Glycopeptides
Teicoplanin Targocid

inhibiting peptidoglycan synthesis
Vancomycin Vancocin
Telavancin Vibativ
Lincosamides
Clindamycin Cleocin Serious staph-, pneumo-, and streptococcal infections in penicillin-allergic patients, also anaerobic infections; clindamycin topically for acne Possible C. difficile-related pseudomembranous enterocolitis Bind to 50S subunit of bacterial RNA thereby inhibiting protein synthesis
Lincomycin Lincocin
Lipopeptide
Daptomycin Cubicin Gram-positive organisms
Bind to the membrane and cause rapid depolarization, resulting in a loss of membrane potential leading to inhibition of protein, DNA and RNA synthesis
Macrolides
Azithromycin Zithromax, Sumamed, Zitrocin Streptococcal infections, syphilis, upper respiratory tract infections, lower respiratory tract infections, mycoplasmal infections, Lyme disease
  • Nausea, vomiting, and diarrhea (especially at higher doses)
  • Jaundice
inhibition of bacterial protein biosynthesis by binding reversibly to the subunit 50S of the bacterial ribosome, thereby inhibiting translocation of peptidyl tRNA.
Clarithromycin Biaxin
Dirithromycin Dynabac
Erythromycin Erythocin, Erythroped
Roxithromycin
Troleandomycin TAO
Telithromycin Ketek Pneumonia Visual Disturbance, Liver Toxicity.[3]
Spectinomycin Trobicin Gonorrhea
Monobactams
Aztreonam Azactam

Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Nitrofurans
Furazolidone Furoxone Bacterial or protozoal diarrhea or enteritis

Nitrofurantoin Macrodantin, Macrobid Urinary tract infections

Penicillins
Amoxicillin Novamox, Amoxil Wide range of infections; penicillin used for streptococcal infections, syphilis, and Lyme disease Same mode of action as other beta-lactam antibiotics: disrupt the synthesis of the peptidoglycan layer of bacterial cell walls.
Ampicillin Principen
Azlocillin
Carbenicillin Geocillin
Cloxacillin Tegopen
Dicloxacillin Dynapen
Flucloxacillin Floxapen
Mezlocillin Mezlin
Methicillin Staphcillin
Nafcillin Unipen
Oxacillin Prostaphlin
Penicillin G Pentids
Penicillin V Pen-Vee-K
Piperacillin Pipracil
Temocillin Negaban
Ticarcillin Ticar
Penicillin combinations
Amoxicillin/clavulanate Augmentin

The second component prevents bacterial resistance to the first component
Ampicillin/sulbactam Unasyn
Piperacillin/tazobactam Zosyn
Ticarcillin/clavulanate Timentin
Polypeptides
Bacitracin
Eye, ear or bladder infections; usually applied directly to the eye or inhaled into the lungs; rarely given by injection Kidney and nerve damage (when given by injection) Inhibits isoprenyl pyrophosphate, a molecule that carries the building blocks of the peptidoglycan bacterial cell wall outside of the inner membrane [4]
Colistin Coly-Mycin-S Interact with the gram negative bacterial outer membrane and cytoplasmic membrane. It displaces bacterial counter ions, which destabilizes the outer membrane. They act like a detergent against the cytoplasmic membrane, which alters its permeability. Polymyxin B and E are bactericidal even in an isosmotic solution.
Polymyxin B
Quinolones
Ciprofloxacin Cipro, Ciproxin, Ciprobay Urinary tract infections, bacterial prostatitis, community-acquired pneumonia, bacterial diarrhea, mycoplasmal infections, gonorrhea Nausea (rare), irreversible damage to central nervous system (uncommon), tendinosis (rare) inhibit the bacterial DNA gyrase or the topoisomerase IV enzyme, thereby inhibiting DNA replication and transcription.
Enoxacin Penetrex
Gatifloxacin Tequin
Levofloxacin Levaquin
Lomefloxacin Maxaquin
Moxifloxacin Avelox
Nalidixic acid NegGram
Norfloxacin Noroxin
Ofloxacin Floxin, Ocuflox
Trovafloxacin Trovan Withdrawn
Grepafloxacin Raxar Withdrawn
Sparfloxacin Zagam Withdrawn
Temafloxacin Omniflox Withdrawn
Sulfonamides
Mafenide Sulfamylon Urinary tract infections (except sulfacetamide, used for eye infections, and mafenide and silver sulfadiazine, used topically for burns) Folate synthesis inhibition. They are competitive inhibitors of the enzyme dihydropteroate synthetase, DHPS. DHPS catalyses the conversion of PABA (para-aminobenzoate) to dihydropteroate, a key step in folate synthesis. Folate is necessary for the cell to synthesize nucleic acids (nucleic acids are essential building blocks of DNA and RNA), and in its absence cells will be unable to divide.
Sulfonamidochrysoidine (archaic) Prontosil
Sulfacetamide Sulamyd, Bleph-10
Sulfadiazine Micro-Sulfon
Silver sulfadiazine Silvadene
Sulfamethizole Thiosulfil Forte
Sulfamethoxazole Gantanol
Sulfanilimide (archaic)
Sulfasalazine Azulfidine
Sulfisoxazole Gantrisin
Trimethoprim Proloprim, Trimpex
Trimethoprim-Sulfamethoxazole (Co-trimoxazole) (TMP-SMX) Bactrim, Septra
Tetracyclines
Demeclocycline Declomycin Syphilis, chlamydial infections, Lyme disease, mycoplasmal infections, acne rickettsial infections, *malaria *Note: Malaria is caused by a protist and not a bacterium.
  • Gastrointestinal upset
  • Sensitivity to sunlight
  • Potential toxicity to mother and fetus during pregnancy
  • Enamel hypoplasia (staining of teeth; potentially permanent)
  • transient depression of bone growth
inhibiting the binding of aminoacyl-tRNA to the mRNA-ribosome complex. They do so mainly by binding to the 30S ribosomal subunit in the mRNA translation complex.
Doxycycline Vibramycin
Minocycline Minocin
Oxytetracycline Terramycin
Tetracycline Sumycin, Achromycin V, Steclin
Drugs against mycobacteria
Clofazimine Lamprene Antileprotic

Dapsone Avlosulfon Antileprotic

Capreomycin Capastat Antituberculosis

Cycloserine Seromycin Antituberculosis, urinary tract infections

Ethambutol Myambutol Antituberculosis

Ethionamide Trecator Antituberculosis
Inhibits peptide synthesis
Isoniazid I.N.H. Antituberculosis

Pyrazinamide Aldinamide Antituberculosis

Rifampicin (Rifampin in US) Rifadin, Rimactane mostly Gram-positive and mycobacteria Reddish-orange sweat, tears, and urine Binds to the β subunit of RNA polymerase to inhibit transcription
Rifabutin Mycobutin Mycobacterium avium complex rash, discolored urine, GI symptoms
Rifapentine Priftin Antituberculosis

Streptomycin
Antituberculosis Neurotoxicity, ototoxicity As other aminoglycosides
Others
Arsphenamine Salvarsan Spirochaetal infections (obsolete)

Chloramphenicol Chloromycetin meningitis, MRSA, topical use, or for low cost internal treatment. Historic: typhus, cholera. gram negative, gram positive, anaerobes Rarely: aplastic anemia. Inhibits bacterial protein synthesis by binding to the 50S subunit of the ribosome
Fosfomycin Monurol Acute cystitis in women
Inactivates enolpyruvyl transferase, thereby blocking cell wall synthesis
Fusidic acid Fucidin


Linezolid Zyvox VRSA

Metronidazole Flagyl Infections caused by anaerobic bacteria; also amoebiasis, trichomoniasis, Giardiasis Discolored urine, headache, metallic taste, nausea ; alcohol is contraindicated Produces toxic free radicals which disrupt DNA and proteins. This non-specific mechanism is responsible for its activity against a variety of bacteria, amoebae, and protozoa.
Mupirocin Bactroban Ointment for impetigo, cream for infected cuts

Platensimycin



Quinupristin/Dalfopristin Synercid


Rifaximin Xifaxan Traveler's diarrhea caused by E. coli

Thiamphenicol
Gram-negative, Gram-positive, anaerobes. widely used in veterinary medicine. Lacks known anemic side-effects. A chloramphenicol analog. May inhibit bacterial protein synthesis by binding to the 50S subunit of the ribosome
Tigecycline Tigacyl


Tinidazole Tindamax Fasigyn protozoan infections upset stomach, bitter taste, and itchiness
Generic Name Brand Names Common Uses[2] Possible Side Effects[2] Mechanism of action

Twitter Delicious Facebook Digg Stumbleupon Favorites More