Lipids solubilization

Quazepam (88) has a highly fluorinated sidechain so as to make this tranquilizer resistant to dealkylation. It also incorporates a lipid-solubilizing 2-thione moiety. The synthesis begins with bi aryl ketone derivative by ] -al kylation with 2,2,2-trifluoroethyltriclate to give 86. 

The adamantane moiety is of medicinal chemical interest because of its inertness, compactness relative to lipid solubilizing character, and symmetry. Considerable interest, therefore, was engendered by the finding that amantadine (78) was active for the chemoprophylaxis of influenza A in man. There are not many useful chemotherapeutic agents available for the treatment of communicable viral infections, so this finding led to considerable molecular manipulation. The recent abrupt end of the National Influenza Immunization program of 1976 prompted a new look at the nonvaccine means for prophylaxis or treatment of respiratory tract infections due to influenza A, especially in that the well-known antigenic shift or drift of the virus obviates usefulness of the vaccine but not amantadine. 

Surfactants act as solubilizers, stabilizers, emulsiLers, and wetting agents. They can also causi toxicity and disrupt normal membrane structure. Surfactant toxicity is directly related to its concentration. This should be considered by the pharmaceutical formulator so levels below the toxic concentration will be used for a particular application. Many of the toxic effects of the surfactants are related to their physicochemical properties and their interaction with biological membranes and other macromolecular assemblies. The observed protein binding and lipid solubilization is directly... 

Synthetic surfactants Laureth-9 sodium lauryl sulphate polysorbate 20 and 80 PEG-8 laurate sorbitan laurate glyceryl monolaurate saponins (e.g., Quillaja saponins) membrane interaction extraction of membrane proteins and lipids solubilization of peptides... 

The organic solvent was removed by rotary evaporation (40-45°C, 30-60 min). The plasmid DNA solution (1.5 mg/mL in Tris/EDTA buffer) was added to the dry lipid film and the lipids solubilized by vigorous agitation (see Note 3). 

This increase in pH also changes the physical behavior of the fatty acids they become partly ionized (pKa for long-chain fatty acids is approximately 6.4-6.6), migrate to the interface of the emulsified lipid particles, and mediate— together with bile salts, phospholipids, and cholesterol—lipid solubilization. However, in exocrine pancreatic insufficiency, a shortage of pancreatic bicarbonate secretion impairs this neutralization of pH. As a result, the postprandial... 

Recent physical-chemical observations on native mammalian systems reveal that the proposed mixed micellar mechanism of lipid solubilization and transport in both bile and in upper small intestinal contents is incomplete [1,260-263]. Bile is predominantly a mixed micellar solution but, particularly when supersaturated with Ch, also contains small liquid-crystalline vesicles which, as suggested from model systems [239], are another vehicle for Ch and L transport. In dog bile which is markedly unsaturated with Ch [258], these vesicles exist in dilute concentrations and may be markers of the detergent properties of BS on the cells lining the biliary tree and/or related to the mode of bile formation at the level of the canaliculus. In human hepatic bile, which is generally dilute and markedly supersaturated with Ch, these vesicles may be the predominant form of Ch and L solubilization and transport [261]. If hepatic bile is extremely dilute, it is theoretically possible that no BS-L-Ch micelles may be present [268] all of the lipid content may be aggregated... 

The formation of polymers leads to an increase in viscosity. The various lipids that can leach into the frying oil change the properties and the performance of the frying oil. Colored lipids solubilized in the oil contribute to the darkening. Phospholipids are emulsifiers. Traces of liposoluble metal compounds may act as prooxidants. Liposoluble vitamins and phenolic compounds are antioxidants. Volatile compounds (e.g., from fish or onions) contribute to off-flavors. 

Frequent skin contact with paints and coating materials can cause skin disorders, particularly on the hands, in painters and coaters. The lipid-solubilizing properties of the organic solvents may cause or at least promote contact eczema. In particular, paints based on reactive resins (e.g., epoxy and polyester resins) may cause allergic skin disorders. Skin-sensitizing substances include residual monomers and reactive diluents (e.g., acrylates and epoxides) and paint additives (e.g., acid anhydrides. 

In an effort to extend the concept of lipid solubilization to produce solid dosage forms, a solution of drug substance in molten lipid is either coated or dispersed on an inert carrier (Faham et al. 2000 Holm et al. 2007). Several technologies have been... 

Fitzpatrick et al [29] have concluded that NaDS binds to all components of erythrocyte membranes uniformly release of components approximately follows the order of their water solubility, lipid solubilization occurring around the CMC of NaDS. About all the lipid is dissolved at lOmM. Between 2 and 10 mM NaDS (see Fig. 10.4) lipids are solubilized and form mixed micelles capable of solubilizing cholesterol. The exact sequence of events and nature of the comicelles, etc., has still to be elucidated. The authors found the Triton X-100 behaviour difficult to interpret. Although its CMC is 1 mmol 1 Mt is possible... 

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