湿潤剤

関: humectant

WordNet

any substance that is added to another substance to keep it moist
a substance that exerts some force or effect
a businessman who buys or sells for another in exchange for a commission (同)factor, broker
any agent or representative of a federal agency or bureau (同)federal agent
a representative who acts on behalf of other persons or organizations
an active and efficient cause; capable of producing a certain effect; "their research uncovered new disease agents"
how long something has existed; "it was replaced because of its age"
a time of life (usually defined in years) at which some particular qualification or power arises; "she was now of school age"; "tall for his eld" (同)eld
begin to seem older; get older; "The death of his wife caused him to age fast"
make older; "The death of his child aged him tremendously"
the act of making something wet

PrepTutorEJDIC

『代理人』;周旋人 / 働き(作用)を起こすもの;作用物,薬剤 / (政府機関,特にFBI,CIAなどの)部員,機関員
〈U〉(一般に)『年齢』,寿命;〈C〉(個々の)『年齢』,年 / 〈U〉成年(おとなとしての資格・権利を得る年齢;通例18または21歳) / 〈U〉『老齢』;《集合的に》老人たち / 〈U〉(人生の)『一時期』;〈C〉世代(generation) / 〈U〉〈C〉《しばしばA-》(歴史上の)『時代』 / 〈C〉《話》長い間 / 年をとる,ふける;〈物が〉古くなる / 〈年〉'を'とらせる;〈物〉'を'古びさせる
(雨・波で)じづとりぬれること,びしょぬれ

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/10/26 08:08:08」(JST)

wiki en

[Wiki en表示]

Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants.

Schematic diagram of a micelle of oil in aqueous suspension, such as might occur in an emulsion of oil in water. In this example the surfactant molecules' oil-soluble tails project into the oil, while the water-soluble ends remain in contact with the water phase

1 Etymology and definition
2 Composition and structure
- 2.1 Structure of surfactant phases in water
- 2.2 Dynamics of surfactants at interfaces
3 Characterization of interfaces and surfactant layers
- 3.1 Detergents in biochemistry and biotechnology
4 Classification of surfactants
- 4.1 Anionic
  - 4.1.1 Sulfate, sulfonate, and phosphate esters
  - 4.1.2 Carboxylates
- 4.2 Cationic head groups
- 4.3 Zwitterionic surfactants
- 4.4 Nonionic surfactant
- 4.5 According to the composition of their counter-ion
5 Surfactants in pharmacy
6 Current market and forecast
7 Health and environmental controversy
8 Biosurfactants
9 Safety and environmental risks
- 9.1 Biosurfactants and Deepwater Horizon
10 Applications
11 See also
12 References
13 External links

Etymology and definition

The term surfactant is a blend of surface active agent.^[1]

In Index Medicus and the United States National Library of Medicine, surfactant is reserved for the meaning pulmonary surfactant. For the more general meaning, surface active agent/s is the heading.

Schematic diagram of a micelle – the lipophilic tails of the surfactant ions remain inside the oil because they interact more strongly with oil than with water. The polar "heads" of the surfactant molecules coating the micelle interact more strongly with water, so they form a hydrophilic outer layer that forms a barrier between micelles. This inhibits the oil droplets, the hydrophobic cores of micelles, from merging into fewer, larger droplets ("emulsion breaking") of the micelle. The compounds that coat a micelle are typically amphiphilic in nature, meaning that micelles may be stable either as droplets of aprotic solvents such as oil in water, or as protic solvents such as water in oil. When the droplet is aprotic it sometimes is known as a reverse micelle.

Composition and structure

Surfactants are usually organic compounds that are amphiphilic, meaning they contain both hydrophobic groups (their tails) and hydrophilic groups (their heads).^[2] Therefore, a surfactant contains both a water-insoluble (or oil-soluble) component and a water-soluble component. Surfactants will diffuse in water and adsorb at interfaces between air and water or at the interface between oil and water, in the case where water is mixed with oil. The water-insoluble hydrophobic group may extend out of the bulk water phase, into the air or into the oil phase, while the water-soluble head group remains in the water phase.

World production of surfactants is estimated at 15 Mton/y, of which about half are soaps. Other surfactants produced on a particularly large scale are linear alkylbenzenesulfonates (1700 kton/y), lignin sulfonates (600 kton/y), fatty alcohol ethoxylates (700 ktons/y), and alkylphenol ethoxylates (500 kton/y).^[3]

Sodium stearate, the most common component of most soap, which comprises about 50% of commercial surfactants.
4-(5-Dodecyl) benzenesulfonate, a linear dodecylbenzenesulfonate, one of the most common surfactants.

Structure of surfactant phases in water

In the bulk aqueous phase, surfactants form aggregates, such as micelles, where the hydrophobic tails form the core of the aggregate and the hydrophilic heads are in contact with the surrounding liquid. Other types of aggregates can also be formed, such as spherical or cylindrical micelles or lipid bilayers. The shape of the aggregates depends on the chemical structure of the surfactants, namely the balance in size between hydrophilic head and hydrophobic tail. A measure of this is the HLB, Hydrophilic-lipophilic balance. Surfactants reduce the surface tension of water by adsorbing at the liquid-air interface. The relation that links the surface tension and the surface excess is known as the Gibbs isotherm.

Dynamics of surfactants at interfaces

The dynamics of surfactant adsorption is of great importance for practical applications such as in foaming, emulsifying or coating processes, where bubbles or drops are rapidly generated and need to be stabilized. The dynamics of adsorption depend on the diffusion coefficient of the surfactant. As the interface is created, the adsorption is limited by the diffusion of the surfactant to the interface. In some cases, there can exist an energetic barrier to adsorption or desorption of the surfactant. If such a barrier limits the adsorption rate, the dynamics are said to be ‘kinetically limited'. Such energy barriers can be due to steric or electrostatic repulsions. The surface rheology of surfactant layers, including the elasticity and viscosity of the layer, play an important role in the stability of foams and emulsions.

Characterization of interfaces and surfactant layers

Interfacial and surface tension can be characterized by classical methods such as the -pendant or spinning drop method. Dynamic surface tensions, i.e. surface tension as a function of time, can be obtained by the maximum bubble pressure apparatus

The structure of surfactant layers can be studied by ellipsometry or X-Ray reflectivity.

Surface rheology can be characterized by the oscillating drop method or shear surface rheometers such as double-cone, double-ring or magnetic rod shear surface rheometer.

Detergents in biochemistry and biotechnology

In solution, detergents help solubilize a variety of chemical species by dissociating aggregates and unfolding proteins. Popular surfactants in the biochemistry laboratory are SDS and CTAB. Detergents are key reagents to extract protein by lysis of the cells and tissues: They disorganize the membrane's lipidic bilayer (SDS, Triton X-100, X-114, CHAPS, DOC, and NP-40), and solubilize proteins. Milder detergents such as octyl thioglucoside, octyl glucoside or dodecyl maltoside are used to solubilize membrane proteins such as enzymes and receptors without denaturing them. Non-solubilized material is harvested by centrifugation or other means. For electrophoresis, for example, proteins are classically treated with SDS to denature the native tertiary and quaternary structures, allowing the separation of proteins according to their molecular weight.

Detergents have also been used to decellularise organs. This process maintains a matrix of proteins that preserves the structure of the organ and often the microvascular network. The process has been successfully used to prepare organs such as the liver and heart for transplant in rats.^[4] Pulmonary surfactants are also naturally secreted by type II cells of the lung alveoli in mammals.

Classification of surfactants

The "tail" of most surfactants are fairly similar, consisting of a hydrocarbon chain, which can be branched, linear, or aromatic. Fluorosurfactants have fluorocarbon chains. Siloxane surfactants have siloxane chains.

Many important surfactants include a polyether chain terminating in a highly polar anionic group. The polyether groups often comprise ethoxylated (polyethylene oxide-like) sequences inserted to increase the hydrophilic character of a surfactant. Polypropylene oxides conversely, may be inserted to increase the lipophilic character of a surfactant.

Surfactant molecules have either one tail or two; those with two tails are said to be double-chained.

Surfactant classification according to the composition of their head: nonionic, anionic, cationic, amphoteric.

Most commonly, surfactants are classified according to polar head group. A non-ionic surfactant has no charged groups in its head. The head of an ionic surfactant carries a net positive, or negetive charge. If the charge is negative, the surfactant is more specifically called anionic; if the charge is positive, it is called cationic. If a surfactant contains a head with two oppositely charged groups, it is termed zwitterionic. Commonly encountered surfactants of each type include:

Anionic

Sulfate, sulfonate, and phosphate esters

Anionic surfactants contain anionic functional groups at their head, such as sulfate, sulfonate, phosphate, and carboxylates. Prominent alkyl sulfates include ammonium lauryl sulfate, sodium lauryl sulfate (SDS, sodium dodecyl sulfate, another name for the compound) and the related alkyl-ether sulfates sodium laureth sulfate, also known as sodium lauryl ether sulfate (SLES), and sodium myreth sulfate.

Docusates: dioctyl sodium sulfosuccinate, perfluorooctanesulfonate (PFOS), perfluorobutanesulfonate, linear alkylbenzene sulfonates (LABs).

These include alkyl-aryl ether phosphates and the alkyl ether phosphate

Carboxylates

These are the most common surfactants and comprise the alkyl carboxylates (soaps), such as sodium stearate. More specialized species include sodium lauroyl sarcosinate and carboxylate-based fluorosurfactants such as perfluorononanoate, perfluorooctanoate (PFOA or PFO).

Cationic head groups

pH-dependent primary, secondary, or tertiary amines: Primary and secondary amines become positively charged at pH < 10:"Bordwell pKa Table (Acidity in DMSO)". Retrieved 11 May 2014.
- Octenidine dihydrochloride;
Permanently charged quaternary ammonium cation:
- Alkyltrimethylammonium salts: cetyl trimethylammonium bromide (CTAB) a.k.a. hexadecyl trimethyl ammonium bromide, cetyl trimethylammonium chloride (CTAC)
- Cetylpyridinium chloride (CPC)
- Benzalkonium chloride (BAC)
- Benzethonium chloride (BZT)
- 5-Bromo-5-nitro-1,3-dioxane
- Dimethyldioctadecylammonium chloride
- Cetrimonium bromide
- Dioctadecyldimethylammonium bromide (DODAB)

Zwitterionic surfactants

Zwitterionic (amphoteric) surfactants have both cationic and anionic centers attached to the same molecule. The cationic part is based on primary, secondary, or tertiary amines or quaternary ammonium cations. The anionic part can be more variable and include sulfonates, as in the sultaines CHAPS (3-[(3-Cholamidopropyl)dimethylammonio]-1-propanesulfonate) and cocamidopropyl hydroxysultaine. Betaines such as cocamidopropyl betaine have a carboxylate with the ammonium. The most common biological zwitterionic surfactants have a phosphate anion with an amine or ammonium, such as the phospholipids phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelins.

Nonionic surfactant

Many long chain alcohols exhibit some surfactant properties. Prominent among these are the fatty alcohols, cetyl alcohol, stearyl alcohol, and cetostearyl alcohol (consisting predominantly of cetyl and stearyl alcohols), and oleyl alcohol.

Polyoxyethylene glycol alkyl ethers (Brij): CH₃–(CH₂)_10–16–(O-C₂H₄)_1–25–OH:
- Octaethylene glycol monododecyl ether
- Pentaethylene glycol monododecyl ether
Polyoxypropylene glycol alkyl ethers: CH₃–(CH₂)_10–16–(O-C₃H₆)_1–25–OH
Glucoside alkyl ethers: CH₃–(CH₂)_10–16–(O-Glucoside)_1–3–OH:
- Decyl glucoside,
- Lauryl glucoside
- Octyl glucoside
Polyoxyethylene glycol octylphenol ethers: C₈H₁₇–(C₆H₄)–(O-C₂H₄)_1–25–OH:
- Triton X-100
Polyoxyethylene glycol alkylphenol ethers: C₉H₁₉–(C₆H₄)–(O-C₂H₄)_1–25–OH:
- Nonoxynol-9
Glycerol alkyl esters:
- Glyceryl laurate
Polyoxyethylene glycol sorbitan alkyl esters: Polysorbate
Sorbitan alkyl esters: Spans
Cocamide MEA, cocamide DEA
Dodecyldimethylamine oxide
Block copolymers of polyethylene glycol and polypropylene glycol: Poloxamers
Polyethoxylated tallow amine (POEA).

According to the composition of their counter-ion

In the case of ionic surfactants, the counter-ion can be:

Monatomic / Inorganic:
- Cations: metals : alkali metal, alkaline earth metal, transition metal
- Anions: halides: chloride (Cl⁻), bromide (Br⁻), iodide (I⁻)
Polyatomic / Organic:
- Cations: ammonium, pyridinium, triethanolamine (TEA)
- Anions: tosyls, trifluoromethanesulfonates, methyl sulfate

Surfactants in pharmacy

A wetting agent is a surfactant that, when dissolved in water, lowers the advancing contact angle, aids in displacing an air phase at the surface, and replaces it with a liquid phase. Examples of application of wetting to pharmacy and medicine include the displacement of air from the surface of sulfur, charcoal, and other powders for the purpose of dispersing these drugs in liquid vehicles; the displacement of air from the matrix of cotton pads and bandages so that medicinal solutions can be absorbed for application to various body areas; the displacement of dirt and debris by the use of detergents in the washing of wounds; and the application of medicinal lotions and sprays to surface of skin and mucous membranes.

Current market and forecast

The annual global production of surfactants was 13 million tonnes in 2008.^[5]^[6] In 2014, the world market for surfactants reached a volume of more than 33 billion US-dollars. Market researchers expect annual revenues to increase by 2.5% per year to around 40.4 billion US-dollars until 2022. The commercially most significant type of surfactants is currently the anionic surfactant alkyl benzene sulfonate (LAS), which is widely used in cleaners and detergents.^[7]

Health and environmental controversy

Surfactants are routinely deposited in numerous ways on land and into water systems, whether as part of an intended process or as industrial and household waste. Some of them are known to be toxic to animals, ecosystems, and humans, and can increase the diffusion of other environmental contaminants.^[8]^[9]^[10] As a result, there are proposed or voluntary restrictions on the use of some surfactants. For example, PFOS is a persistent organic pollutant as judged by the Stockholm Convention. Additionally, PFOA has been subject to a voluntary agreement by the U.S. Environmental Protection Agency and eight chemical companies to reduce and eliminate emissions of the chemical and its precursors.^[11]

The two major surfactants used in the year 2000 were linear alkylbenzene sulfonates (LAS) and the alkyl phenol ethoxylates (APE). They break down in the aerobic conditions found in sewage treatment plants and in soil to the metabolite nonylphenol, which is thought to be an endocrine disruptor.^[12]^[13]

Ordinary dishwashing detergent, for example, will promote water penetration in soil, but the effect would last only a few days (many standard laundry detergent powders contain levels of chemicals such as alkali and chelating agents that can be damaging to plants and should not be applied to soils). Commercial soil wetting agents will continue to work for a considerable period, but they will eventually be degraded by soil micro-organisms. Some can, however, interfere with the life-cycles of some aquatic organisms, so care should be taken to prevent run-off of these products into streams, and excess product should not be washed down.^{[citation needed]}

Anionic surfactants can be found in soils as the result of sludge application, wastewater irrigation, and remediation processes. Relatively high concentrations of surfactants together with multimetals can represent an environmental risk. At low concentrations, surfactant application is unlikely to have a significant effect on trace metal mobility.^[14]^[15]

Biosurfactants

Biosurfactants are surface-active substances synthesised by living cells. Interest in microbial surfactants has been steadily increasing in recent years due to their diversity, environmentally friendly nature, possibility of large-scale production, selectivity, performance under extreme conditions, and potential applications in environmental protection.^[16]^[17] A few of the popular examples of microbial biosurfactants includes Emulsan produced by Acinetobacter calcoaceticus,^[18] Sophorolipids produced by several yeasts belonging to candida and the starmerella clade,^[19]^[20] and Rhamnolipid produced by Pseudomonas aeruginosa^[21] etc.

Biosurfactants enhance the emulsification of hydrocarbons, have the potential to solubilise hydrocarbon contaminants and increase their availability for microbial degradation. The use of chemicals for the treatment of a hydrocarbon polluted site may contaminate the environment with their by-products, whereas biological treatment may efficiently destroy pollutants, while being biodegradable themselves. Hence, biosurfactant-producing microorganisms may play an important role in the accelerated bioremediation of hydrocarbon-contaminated sites.^[22]^[23]^[24] These compounds can also be used in enhanced oil recovery and may be considered for other potential applications in environmental protection.^[24]^[25] Other applications include herbicides and pesticides formulations, detergents, healthcare and cosmetics, pulp and paper, coal, textiles, ceramic processing and food industries, uranium ore-processing, and mechanical dewatering of peat.^[16]^[17]^[26]

Several microorganisms are known to synthesise surface-active agents; most of them are bacteria and yeasts.^[27]^[28] When grown on hydrocarbon substrate as the carbon source, these microorganisms synthesise a wide range of chemicals with surface activity, such as glycolipid, phospholipid, and others.^[29]^[30] These chemicals are synthesised to emulsify the hydrocarbon substrate and facilitate its transport into the cells. In some bacterial species such as Pseudomonas aeruginosa, biosurfactants are also involved in a group motility behavior called swarming motility.

Safety and environmental risks

Most anionic and nonionic surfactants are nontoxic, having LD50 comparable to sodium chloride. The situation for cationic surfactants is more diverse. Dialkyldimethylammonium chlorides have very low LD50's (5 g/kg) but alkylbenzyldimethylammonium chloride has an LD50 of 0.35 g/kg. Prolonged exposure of skin to surfactants can cause chafing because surfactants (e.g., soap) disrupts the lipid coating that protects skin (and other) cells.^[3]

Biosurfactants and Deepwater Horizon

The use of biosurfactants as a way to remove petroleum from contaminated sites has been studied and found to be safe and effective in the removal of petroleum products from soil. Other studies found that surfactants are often more toxic than the oil that is being dispersed, and the combination of the oil and the surfactant can be more toxic than either alone. Biosurfactants were not used by BP after the Deepwater Horizon oil spill. However, unprecedented amounts of Corexit (active ingredient: Tween-80), were sprayed directly into the ocean at the leak and on the sea-water's surface, the theory being that the surfactants isolate droplets of oil, making it easier for petroleum-consuming microbes to digest the oil.

Applications

Surfactants play an important role as cleaning, wetting, dispersing, emulsifying, foaming and anti-foaming agents in many practical applications and products, including:

Detergents
Fabric softeners
Emulsions
Paints
Adhesives
Inks
Anti-fogs
Ski waxes, snowboard wax
Deinking of recycled papers, in flotation, washing and enzymatic processes
Laxatives
Agrochemical formulations
- Herbicides (some)
- Insecticides
Quantum dot in order to manipulate growth^[31] and assembly of the dots, reactions on their surface, electrical properties, etc., it is important to understand how surfactants arrange^[32] on the surface of the quantum dots
Biocides (sanitizers)
Cosmetics:
- Shampoos
- Hair conditioners (after shampoo)
- Toothpastes
Spermicides (nonoxynol-9)
Firefighting
Pipelines, liquid drag reducing agent
Alkali Surfactant Polymers (used to mobilize oil in oil wells)
Ferrofluids
Leak Detectors

References

^ Rosen MJ and Kunjappu JT (2012). Surfactants and Interfacial Phenomena (4th ed.). Hoboken, New Jersey: John Wiley & Sons. p. 1. ISBN 1-118-22902-9.
^ "Bubbles, Bubbles, Everywhere, But Not a Drop to Drink". The Lipid Chronicles. Retrieved 1 August 2012.
^ ^a ^b Kurt Kosswig "Surfactants" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, 2005, Weinheim. doi:10.1002/14356007.a25_747
^ Wein, Harrison (28 June 2010). "Progress Toward an Artificial Liver Transplant – NIH Research Matters". National Institutes of Health (NIH).
^ "Market Report: World Surfactant Market". Acmite Market Intelligence.
^ Reznik, Gabriel O.; Vishwanath, Prashanth; Pynn, Michelle A.; Sitnik, Joy M.; Todd, Jeffrey J.; Wu, Jun; Jiang, Yan; Keenan, Brendan G.; et al. (2010). "Use of sustainable chemistry to produce an acyl amino acid surfactant". Applied Microbiology and Biotechnology 86 (5): 1387–97. doi:10.1007/s00253-009-2431-8. PMID 20094712.
^ Market Study on Surfactants (2nd edition, April 2015), by Ceresana Research
^ Metcalfe, Tracy L.; Dillon, Peter J.; Metcalfe, Chris D. (2008). "DETECTING THE TRANSPORT OF TOXIC PESTICIDES FROM GOLF COURSES INTO WATERSHEDS IN THE PRECAMBRIAN SHIELD REGION OF ONTARIO, CANADA". Environmental Toxicology and Chemistry 27 (4): 811–8. doi:10.1897/07-216.1. PMID 18333674.
^ Emmanuel, E; Hanna, K; Bazin, C; Keck, G; Clement, B; Perrodin, Y (2005). "Fate of glutaraldehyde in hospital wastewater and combined effects of glutaraldehyde and surfactants on aquatic organisms". Environment International 31 (3): 399–406. doi:10.1016/j.envint.2004.08.011. PMID 15734192.
^ Murphy, M; Alkhalidi, M; Crocker, J; Lee, S; Oregan, P; Acott, P (2005). "Two formulations of the industrial surfactant, Toximul, differentially reduce mouse weight gain and hepatic glycogen in vivo during early development: effects of exposure to Influenza B Virus". Chemosphere 59 (2): 235–46. doi:10.1016/j.chemosphere.2004.11.084. PMID 15722095.
^ USEPA: "2010/15 PFOA Stewardship Program" Accessed October 26, 2008.
^ Mergel, Maria. "Nonylphenol and Nonylphenol Ethoxylates." Toxipedia.org. N.p., 1 Nov. 2011. Web. 27 Apr. 2014.
^ Scott, M; Jones, Malcolm N (2000). "The biodegradation of surfactants in the environment". Biochimica et Biophysica Acta (BBA) – Biomembranes 1508: 235–251. doi:10.1016/S0304-4157(00)00013-7.
^ Hernández-Soriano Mdel, C; Degryse, F; Smolders, E (2011). "Mechanisms of enhanced mobilisation of trace metals by anionic surfactants in soil". Environmental pollution (Barking, Essex : 1987) 159 (3): 809–16. doi:10.1016/j.envpol.2010.11.009. PMID 21163562.
^ Hernández-Soriano Mdel, C; Peña, A; Dolores Mingorance, M (2010). "Release of metals from metal-amended soil treated with a sulfosuccinamate surfactant: effects of surfactant concentration, soil/solution ratio, and pH". Journal of environmental quality 39 (4): 1298–305. doi:10.2134/jeq2009.0242. PMID 20830918.
^ ^a ^b Banat, I. M., Makkar, R. S., Cameotra, S. S. (2000). "Potential commercial applications of microbial surfactants". Appl. Microbiol. Biotechnol. 53 (5): 495–508. doi:10.1007/s002530051648. PMID 10855707.
^ ^a ^b Rahman, K. S. M., Thahira-Rahman, J., McClean, S., Marchant, R., Banat, I.M (2002). "Rhamnolipid biosurfactants production by strains of Pseudomonas aeruginosa using low cost raw materials". Biotechnol Prog. 18 (6): 1277–1281. doi:10.1021/bp020071x. PMID 12467462.
^ Shoham, Y; Rosenberg, M; Rosenberg, E (1983). "Bacterial degradation of emulsan". Appl. Environ. Microbiol 46 (3): 573–579. PMID 6688940.
^ Kurtzman, C. P.; Price, N. P.; Ray, K. J.; Kuo, T. M. (2010). "Production of sophorolipid biosurfactants by multiple strains of the Starmerella (Candida) bombicola yeast clade". FEMS Microbiol Lett 311 (2): 140–146. doi:10.1111/j.1574-6968.2010.02082.x.
^ Parekh, V. J.; Pandit, A. B. (2011). "Optimization of fermentative production of sophorolipid biosurfactant by starmerella bombicola NRRL Y-17069 using response surface methodology". International Journal of Pharmacy and Biological Sciences 1 (3): 103–116.
^ Ito, S; Honda, H; Tomita, F; Suzuki, T (Dec 1971). "Rhamnolipids produced by Pseudomonas aeruginosa grown on n-paraffin (mixture of C 12 , C 13 and C 14 fractions)". J Antibiot (Tokyo) 24 (12): 855–859. doi:10.7164/antibiotics.24.855.
^ Rosenberg, E., Ron, E. Z (1999). "High and low molecular mass microbial surfactants". Appl. Microbiol. Biotechnol. 52 (2): 154–162. doi:10.1007/s002530051502. PMID 10499255.
^ Del ‘Arco, J. P., De Franca, F. P (2001). "Influence of oil contamination levels on hydrocarbon biodegradation in sandy sediments". Environ. Pollut. 110: 515–519.
^ ^a ^b Rahman, K. S. M., Banat, I.M., Thahira-Rahman, J., Thayumanavan, T., Lakshmanaperumalsamy, P (2002). "Bioremediation of gasoline contaminated soil by a bacterial consortium amended with poultry litter, coir pith and rhamnolipid biosurfactant". Bioresource Technol. 81: 25–32. doi:10.1016/S0960-8524(01)00105-5.
^ Shulga, A., Karpenko, E., Vildanova-Martsishin, R., Turovsky, A., Soltys, M (1999). "Biosurfactant enhanced remediation of oil-contaminated environments". Adsorpt. Sci. Technol. 18: 171–176. doi:10.1260/0263617001493369.
^ Ron, E. Z., Rosenberg, E (2001). "Natural roles of biosurfactants". Environ. Microbiol. 3 (4): 229–236. doi:10.1046/j.1462-2920.2001.00190.x. PMID 11359508.
^ Banat, I. M (1995). "Biosurfactants production and possible uses in microbial enhanced oil recovery and oil pollution remediation: a review". Bioresource Technol. 51: 1–12. doi:10.1016/0960-8524(94)00101-6.
^ Kim, S.E., Lim, E. J., Lee, S.O., Lee , J. D., Lee, T.H (2000). "Purification and characterisation of biosurfactants from Nocardia sp. L-417". Biotechnol. Appl. Biochem. 31 (3): 249–253. doi:10.1042/BA19990111.
^ Muriel, J.M., Bruque, J.M., Olias, J.M., Sanchez, A. J (1996). "Production of biosurfactants by Cladosporium resinae". Biotechnol. Lett. 18 (3): 235–240. doi:10.1007/BF00142937.
^ Desai, J.D., Banat, I.M (1997). "Microbial production of surfactants and their commercial potential". Microbiol. Mol. Biol. Rev. 61 (1): 47–64. PMC 232600. PMID 9106364.
^ Murray, C. B.; Kagan, C. R.; Bawendi, M. G. (2000). "Synthesis and Characterization of Monodisperse Nanocrystals and Close-Packed Nanocrystal Assemblies". Annual Review of Materials Research 30 (1): 545–610. Bibcode:2000AnRMS..30..545M. doi:10.1146/annurev.matsci.30.1.545.
^ Zherebetskyy D, Scheele M, Zhang Y, Bronstein N, Thompson C, Britt D, Salmeron M, Alivisatos P, Wang LW. (2014). "Hydroxylation of the surface of PbS nanocrystals passivated with oleic acid". Science 344 (6190): 1380–1384. doi:10.1126/science.1252727.

External links

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. コンタクトレンズの概要 overview of contact lenses
2. 手術室で使用される局所止血剤および組織接着剤の概要 overview of topical hemostatic agents and tissues adhesives used in the operating room
3. 前立腺癌の危険因子 risk factors for prostate cancer
4. 第二世代（非定型）抗精神病薬中毒 second generation atypical antipsychotic medication poisoning
5. 第一世代（定型）抗精神病剤中毒 first generation typical antipsychotic medication poisoning

English Journal

Glycolipid biosurfactants: Potential related biomedical and biotechnological applications.

Inès M1, Dhouha G2.
Carbohydrate research.Carbohydr Res.2015 Oct 30;416:59-69. doi: 10.1016/j.carres.2015.07.016. Epub 2015 Jul 31.
Glycolipids, consisting of a carbohydrate moiety linked to fatty acids, are microbial surface active compounds produced by various microorganisms. They are characterized by highly structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface r
PMID 26359535

Formation, characterization and stability of oil nanodroplets on immersed substrates.

Xu H1, Zhang X2.
Advances in colloid and interface science.Adv Colloid Interface Sci.2015 Oct;224:17-32. doi: 10.1016/j.cis.2015.07.004. Epub 2015 Jul 19.
Nanoscale oil droplets locating at solid-liquid interfaces significantly impact the interfacial properties, which are concerned in both industry applications and fundamental studies. This review article presents an overview of the current progress in nanodroplet research. We will start from the char
PMID 26233493

Optimizing a wet granulation process to obtain high-dose sustained-release tablets with Compritol 888 ATO.

Rosiaux Y1, Girard JM1, Desvignes F1, Miolane C1, Marchaud D1.
Drug development and industrial pharmacy.Drug Dev Ind Pharm.2015 Oct;41(10):1738-44. doi: 10.3109/03639045.2014.1002410. Epub 2015 Feb 5.
CONTEXT: Niacin (vitamin B3) is a micronized active pharmaceutical ingredient (API) with poor flow properties making the production of high-dose sustained-release tablets by direct compression a challenge.OBJECTIVE: We evaluated various wet granulation processes as a simple and efficient approach to
PMID 25652358