TY - JOUR
T1 - Rapid insight into heating-induced phase transformations in the solid state of the calcium salt of atorvastatin using multivariate data analysis
AU - Christensen, Niels Peter Aae
AU - Van Eerdenbrugh, Bernard
AU - Kwok, Kaho
AU - Taylor, Lynne S.
AU - Bond, Andrew
AU - Rades, Thomas
AU - Rantanen, Jukka
AU - Cornett, Claus
PY - 2013/3
Y1 - 2013/3
N2 - Purpose: To investigate the heating-induced dehydration and melting behavior of the trihydrate phase of the calcium salt of atorvastatin. Methods: Multivariate curve resolution (MCR) was used to decompose a variable-temperature synchrotron X-ray powder diffraction (VT-XRPD) data matrix into diffraction patterns and concentration profiles of pure drug phases. Results: By means of the MCR-estimated diffraction patterns and concentration profiles, the trihydrate phase of the drug salt was found to dehydrate sequentially into two partially dehydrated hydrate structures upon heating from 25 to 110 C, with no associated breakage of the original crystal lattice. During heating from 110 to 140 C, the remaining water was lost from the solid drug salt, which instantly collapsed into a liquid crystalline phase. An isotropic melt was formed above 155 C. Thermogravimetric analysis, hot-stage polarized light microscopy, and hot-stage Raman spectroscopy combined with principal component analysis (PCA) was shown to provide consistent results. Conclusions: This study demonstrates that MCR combined with VT-XRPD is a powerful tool for rapid interpretation of complex dehydration behavior of drug hydrates, and it is also the first report on a liquid crystalline phase of the calcium salt of atorvastatin.
AB - Purpose: To investigate the heating-induced dehydration and melting behavior of the trihydrate phase of the calcium salt of atorvastatin. Methods: Multivariate curve resolution (MCR) was used to decompose a variable-temperature synchrotron X-ray powder diffraction (VT-XRPD) data matrix into diffraction patterns and concentration profiles of pure drug phases. Results: By means of the MCR-estimated diffraction patterns and concentration profiles, the trihydrate phase of the drug salt was found to dehydrate sequentially into two partially dehydrated hydrate structures upon heating from 25 to 110 C, with no associated breakage of the original crystal lattice. During heating from 110 to 140 C, the remaining water was lost from the solid drug salt, which instantly collapsed into a liquid crystalline phase. An isotropic melt was formed above 155 C. Thermogravimetric analysis, hot-stage polarized light microscopy, and hot-stage Raman spectroscopy combined with principal component analysis (PCA) was shown to provide consistent results. Conclusions: This study demonstrates that MCR combined with VT-XRPD is a powerful tool for rapid interpretation of complex dehydration behavior of drug hydrates, and it is also the first report on a liquid crystalline phase of the calcium salt of atorvastatin.
U2 - 10.1007/s11095-012-0923-1
DO - 10.1007/s11095-012-0923-1
M3 - Journal article
C2 - 23138263
SN - 0724-8741
VL - 30
SP - 826
EP - 835
JO - Pharmaceutical Research
JF - Pharmaceutical Research
IS - 3
ER -