- Effect of hofmeister series anions on the thermotropic phase behavior of bioactive O -acylcholines
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O-Acylcholines (OACs), which are true cationic lipids due to the quaternary ammonium functionality in the headgroup, exhibit interesting biological activities and medicinal properties. In the present study, a homologous series of OACs with even chain lengths (n = 12-20) have been synthesized, and their thermotropic and chaotropic phase transitions have been characterized. The role of various anions (Cl-, Br-, I-, NO 3-, SO42-, ClO3 -, ClO4-) on the phase behavior of O-stearoylcholine was investigated by calorimetric, spectroscopic, and turbidimetric approaches. The results obtained revealed that in aqueous dispersion O-stearoylcholine undergoes a cooperative phase transition from a gel phase to a micellar structure and that the transition temperature increases when the counterions are changed in the Hofmeister series. Single-crystal X-ray diffraction studies showed that O-stearoylcholine iodide forms an interdigitated bilayer structure, with the polymethylene chain adopting an all-trans conformation. The Hofmeister effect and phase behavior were explained using the concepts of matching water affinities, water penetration into the bilayer, and electrostatic repulsion. It was also observed that one counterion per molecule is sufficient to strongly modulate the phase properties of the lipid/surfactant.
- Tarafdar, Pradip K.,Reddy, S. Thirupathi,Swamy, Musti J.
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p. 9900 - 9909
(2013/09/23)
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- Sustained release pharmaceutical compositions
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The present invention relates to a pharmaceutical composition comprising a salt of quaternary ammonium of an acid drug in the form of a suspension or an emulsion, suitable for parenteral administration and providing a sustained release of the drug. In one preferred embodiment, the present invention is directed to a long term sustained release composition for parenteral administration, comprising a salt of heparin or low molecular weight heparin in an emulsion with a salt of acylcholine, for the prevention and treatment of venous thrombosis and pulmonary embolism.
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Page/Page column 6
(2008/06/13)
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- Softener composition
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A softener composition that can impart a high softening effect to clothes irrespective of the state of rinsing water, which contains (a) a compound of formula (1) below, (b) a compound of formula (3) below, and (c) a specific anionic surfactant, wherein the mole ratios between the components (a), (b) and (c) satisfy the following relationship: [(a)+(b)]/(c)=9/1 to 4/6; and wherein R1 represents a C13-36 alkyl group or the like, R10 and R12 respectively represent a C8-36 alkyl group or the like, R2, R11 and R13 respectively represent a C1-6 alkylene group, R3, R4, and R14 respectively represent a C1-3 alkyl group or the like, A, D and E respectively represent —COO—, —CONH— or the like, and “a”, “c” and “d” respectively denote 0 or 1.
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Page/Page column 6-7
(2008/06/13)
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