Lipophilicity, hydrophobic organic compounds

Lipophilic (lipid loving) Such organic compounds tend to be of low polarity and are hydrophobic. 

Mannhold, R., Rekker, R. F., Dross, K., Bijloo, G., De Vries, G. The lipophilic behaviour of organic compounds 1. An updating of the hydrophobic fragmental... 

Microbes were frequently found to synthesise surface-active molecules in order to mobilise hydrophobic organic substrates. These biosurfactants, which are either excreted by the producing organisms or remain bound to their cell surfaces, are composed of a hydrophilic part making them soluble in water and a lipophilic part making them accumulate at interfaces. With respect to their physical effects, one can distinguish two types of biosurfactants firstly, molecules that drastically reduce the surface and interfacial tensions of gas-liquid, liquid-liquid and liquid-solid systems, and, secondly, compounds that stabilise emulsions of nonaqueous phase liquids in water, often also referred to as bioemulsifiers. The former molecules are typically low-molar-mass... 

The hydrophobicity of an organic molecule is quantified by means of its partition coefficient between octanol and water (Kow)- Kow is equal to the ratio of compound concentrations at saturation in n-octanol and in water at equilibrium and at a specific temperature. n-Octanol possesses structural properties analogous to lipidic tissues of organisms, and so Kow allows evaluation of the lipophilic character of the contaminant and thus of its capacity to be accumulated in the lipidic tissues of living organisms. The Kow value of hydrophobic organic pollutants (HOPs) is higher than 100. They are nonpolar molecules with a low water solubility. Their weak solubility and their hydrophobicity... 

Furthermore, an empirical hydrophobicity parameter derived from measurements of the distribution of a solute between two immiscible liquids should be mentioned cf. Section 2.2.7 dealing with hydrophobic interactions. The hydrophobic or lipophilic character of organic compounds plays an important role in their abihty to interfere with biochemical systems. Therefore, systematic efforts have been made to obtain numerically defined constants to assess the hydrophobic character of organic compounds. A hydrophobicity parameter which has proven quite valuable in the fields of toxicology, pharmacology, and environmental science is the Hansch-Leo 1-octanollwater partition coefficient TiTo/w or Pq/w as defined in Eq. (7-12),... 

It is also noteworthy that micelle-forming surfactants may solubilize organic compounds sometimes in a very low concentration of the surfactant (still above the CMC). This embedding depends on the charge of surfactant and the charge of reactant. Only hydrophobic reactants may permeate into the hydrophobic core. Important for good solubilization properties is the hydrophile-lipophile balance (HLB) of the surfactant because sufficient water-solubility is required [12] (cf. Sec-... 

Dioxins are a family of the most toxic chlorinated organic compounds known to science, numbering around 75 dioxins and 135 related furans. These can cause cancer and are ECD for humans, even at very low exposure levels, since minute amounts, can bio-accumulate due to their ease of solubility in body fat (dioxins are hydrophobic, water-hating and lipophilic, fat-loving ). Number and position of chlorine atoms in the molecule has a considerable effect on toxicity, and 17 dioxins are classed as highly toxic. These include polychlorinated dioxins (PCDD) and dibenzofurans (PCDF) which are by-products of the chlorine bleaching of paper, the burning of chlorinated hydrocarbons (such as pentachlorophenol, PCB, and PVC) and the incineration of municipal/medical... 

Generally, a continuous phase that is a nonsolvent for the microencapsulated bioactive compound is favorable. For lipophilic compounds, aqueous solutions may be comfortably chosen while the use of hydrophobic, organic liquids is preferred as coutinuous phase for the encapsulation of hydrophilic compounds. The ideal rate of solvent removal depends on a variety of factors like the type of matrix material, drug and solvent as weU as the desired release profile of the microspheres. 

Vitamins are organic compounds that have biochemical and physiological proprieties. Because of these qualities, they have been the subject of numerous scientific investigations. Vitamins are classified according to their solu-biUty in water and in fats. Lipophilic (hydrophobic) vitamins are vitamins A, D, E, and K. Chromatography is useful in the identification and determination of vitamins in pharmaceutical preparations, the identification and determination of vitamins and related substances in natural materials and foodstuffs, and the chemical and biochemical determination of vitamins and their metabolites in fats and tissues. 

Calixcrown compounds appear to be a new promising family of carriers for the selective removal of caesium from high salinity and acidity media such as MLW through an SLM. By choosing a highly hydrophobic organic diluent, o-NPOE, and a lipophilic crown-6-calix[4]arene derivative in the 1,3-altemate conformation suitable for caesium complexation over that of sodium, very selective and stable SLMs can be obtained (over a period of 50 days). 

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