Effect of ball-milling on the formation of betulin and betulin diacetate composites with polyethylene glycol

Abstract

Betulin and betulin diacetate (BDA) composites with polyethylene glycol (PEG) were obtained by ball-milling. In case of betulin - PEG mixtures, there was almost complete amorphization under ball-milling. On the contrary, there were no significant changes in the intensity of the reflections in the powder X-ray diffraction patterns for ball-milled mixtures of BDA with PEG. Dissolution of BDA in PEG melts formed at the contacts of particles under collisions with milling bodies leading to crystallization of the drug was suggested. An opportunity to dissolve BDA crystals in PEG melt followed by their crystallization was proven by DSC and hot stage optical microscopic observation