@misc{10481/63111,
year = {2020},
month = {5},
url = {http://hdl.handle.net/10481/63111},
abstract = {The formation of solid dispersions with the amorphous drug dispersed in the polymeric
matrix improves the dissolution characteristics of poorly soluble drugs. Although they provide an
improved absorption after oral administration, the recrystallization, which can occur upon absorption
of moisture or during solidification and other formulation stages, serves as a major challenge.
This work aims at understanding the amorphization-recrystallization changes of bicalutamide.
Amorphous solid dispersions with poly(vinylpyrrolidone-co-vinyl acetate) (PVP/VA) were obtained
by either ball milling or spray drying. The applied processes led to drug amorphization as confirmed
using X-ray diffraction and differential scanning calorimetry. Due to a high propensity towards
mechanical activation, the changes of the crystal structure of physical blends of active pharmaceutical
ingredient (API) and polymer upon pressure were also examined. The compression led to drug
amorphization or transition from form I to form II polymorph, depending on the composition
and applied force. The formation of hydrogen bonds confirmed using infrared spectroscopy and
high miscibility of drug and polymer determined using non-isothermal dielectric measurements
contributed to the high stability of amorphous solid dispersions. They exhibited improved wettability
and dissolution enhanced by 2.5- to 11-fold in comparison with the crystalline drug. The drug
remained amorphous upon compression when the content of PVP/VA in solid dispersions exceeded
20% or 33%, in the case of spray-dried and milled systems, respectively.},
organization = {Polish National Science Centre 	
2015/16/W/NZ7/00404},
publisher = {MDPI},
keywords = {Amorphous solid dispersions},
keywords = {Physical stability},
keywords = {Bicalutamide},
keywords = {Kollidon®VA64},
keywords = {Dissolution},
keywords = {Compression},
title = {Compression-Induced Phase Transitions of Bicalutamide},
doi = {10.3390/pharmaceutics12050438},
author = {Szafraniec Szczesny, Joanna and Rodríguez de Peralta, Sebastián},
}