Inhibiting surface crystallization of amorphous indomethacin by nanocoating
An amorphous solid (glass) may crystallize faster at the surface than through the bulk, making surface crystallization a mechanism of failure for amorphous pharmaceuticals and other materials. An ultrathin coating of gold or polyelectrolytes inhibited the surface crystallization of amorphous indomet...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 23(2007), 9 vom: 24. Apr., Seite 5148-53 |
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| Weitere Verfasser: | , , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2007
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, U.S. Gov't, Non-P.H.S. Electrolytes Polyethylenes Polystyrenes Quaternary Ammonium Compounds Solutions Water 059QF0KO0R poly-N,N-dimethyl-N,N-diallylammonium chloride mehr... |
| Zusammenfassung: | An amorphous solid (glass) may crystallize faster at the surface than through the bulk, making surface crystallization a mechanism of failure for amorphous pharmaceuticals and other materials. An ultrathin coating of gold or polyelectrolytes inhibited the surface crystallization of amorphous indomethacin (IMC), an anti-inflammatory drug and model organic glass. The gold coating (10 nm) was deposited by sputtering, and the polyelectrolyte coating (3-20 nm) was deposited by an electrostatic layer-by-layer assembly of cationic poly(dimethyldiallyl ammonium chloride) (PDDA) and anionic sodium poly(styrenesulfonate) (PSS) in aqueous solution. The coating also inhibited the growth of existing crystals. The inhibition was strong even with one layer of PDDA. The polyelectrolyte coating still permitted fast dissolution of amorphous IMC and improved its wetting and flow. The finding supports the view that the surface crystallization of amorphous IMC is enabled by the mobility of a thin layer of surface molecules, and this mobility can be suppressed by a coating of only a few nanometers. This technique may be used to stabilize amorphous drugs prone to surface crystallization, with the aqueous coating process especially suitable for drugs of low aqueous solubility |
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| Beschreibung: | Date Completed 12.06.2007 Date Revised 19.11.2015 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1520-5827 |