A novel method of producing a microcrystalline beta-sitosterol suspension in oil
Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
This paper describes a novel method of producing a microcrystalline oral suspension containing beta-sitosterol in oil for the treatment of hypercholesterolaemia. beta-Sitosterol pseudopolymorphs with different water contents were crystallized from acetone and acetone-water solutions. Structural analyses of the crystals were performed by Karl-Fisher titration, thermogravimetric analyses, X-ray diffraction and near infrared spectroscopy. The suspensions studied were composed of different concentrations of beta-sitosterol, oil and water. Suspensions were prepared by crystallization of hot concentrated solution of beta-sitosterol in oil by cooling with simultaneous agitation and water addition. The structural analyses of the suspensions were performed by X-ray diffraction, near infrared spectroscopy and optical microscopy. The viscosity of the suspensions was analysed as a function of shear stress. beta-Sitosterol was observed to exist in three different forms: anhydrous, hemihydrated and monohydrated crystals. By changing both the beta-sitosterol and the water concentration of the suspension, the crystal size and shape could be controlled. Addition of water resulted in the formation of monohydrated needle-shaped crystals instead of platy-like anhydrous crystals. Needle-shaped particles formed structured suspensions with shear thinning behaviour. By increasing the volume fraction of solid particles in suspension by increasing the water and/or sterol concentration, the viscosity increased. A high sterol concentration resulted in high supersaturation and thus formation of small crystals.
Originalsprog | Engelsk |
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Tidsskrift | European Journal of Pharmaceutical Sciences |
Vol/bind | 15 |
Udgave nummer | 3 |
Sider (fra-til) | 261-9 |
Antal sider | 9 |
ISSN | 0928-0987 |
Status | Udgivet - apr. 2002 |
- Administration, Oral, Chemistry, Pharmaceutical, Crystallization, Hypercholesterolemia, Hypolipidemic Agents, Oils, Rheology, Sitosterols, Spectroscopy, Near-Infrared, Suspensions, Technology, Pharmaceutical, Thermogravimetry, X-Ray Diffraction
Forskningsområder
ID: 140622846