Liposomes prepared dynamically by interactions between bile salt and phospholipid molecules.

K Son; H Alkan

doi:10.1016/0005-2736(89)90039-4

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PubMed · 2730906

Liposomes prepared dynamically by interactions between bile salt and phospholipid molecules.

K Son·H Alkan

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Abstract

Quasi-elastic light scattering (QELS) studies showed that vesicles can spontaneously form from sodium glycocholate-egg phosphatidylcholine mixed micelles upon dilution with physiological saline buffer (pH 7.5). A water-soluble drug, cytosine arabinoside, did not affect the transition pattern. Transitions were also obtained when dilutions were performed using diluted serum solutions (5% and 10% serum in buffer). However, if intermicellar bile salt monomer concentration (imc) was kept constant in diluent media, the transition was completely suppressed. Approximately 10% of the cytosine arabinoside was trapped inside vesicles which were formed in buffer, although this value decreased to approx. 2.5% when diluted serum was used. These results suggest that the mixed micelle to vesicle transition can be an alternative means to sonication in loading drugs into in vitro vesicles. A good correlation was found between the transmission electron microscopy (TEM) diameter and the mean hydrodynamic diameter obtained by QELS.

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Bile Acids and Salts Blood Chemical Phenomena Chemistry, Physical Cytarabine Humans In Vitro Techniques Light Liposomes Micelles Microscopy, Electron Phosphatidylcholines Scattering, Radiation Journal Article Research Support, Non-U.S. Gov't

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K Son, H Alkan. 1989-06-06. Liposomes prepared dynamically by interactions between bile salt and phospholipid molecules.. https://doi.org/10.1016/0005-2736(89)90039-4

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