The purpose of this research was to develop new methods of increasing dissolution rate and solubility of betulin extracted from birch bark. The ultrafine formulation of betulin with polyethylene glycol and β-glycine was obtained by freeze-drying. The rate of release of betulin from the formulation into water was significantly higher in comparison with the initial betulin sample and its composite with polyethylene glycol obtained by ball-milling.
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8.
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9.
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10.
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13.
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14.
MikhailenkoMA, ShakhtshneiderTP, BrezgunovaME, KuznetsovaSA, BoldyrevVV. (2010) The formulation of betulin with biocompatible polymers and the method of its preparation. RF patent: 401118.
15.
MikhailenkoMA, ShakhtshneiderTP, DrebushchakVA, KuznetsovaSA, SkvortsovaGP, BoldyrevVV. (2011) Influence of mechanical treatment on the properties of betulin, betulin diacetate, and their mixture with water-soluble polymers. Chemistry of Natural Compounds, 47, 229–233.
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18.
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19.
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20.
DrebushchakTN, MikhailenkoMA, BrezgunovaME, ShakhtshneiderTP, KuznetsovaSA. (2010) Crystal structure of betulin ethanol solvate. Journal of Structural Chemistry, 51, 798–801.
21.
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