Screening for differences in the amorphous state of indomethacin using multivariate visualization

Research output: Contribution to journalJournal articlepeer-review

Standard

Screening for differences in the amorphous state of indomethacin using multivariate visualization. / Savolainen, Marja; Heinz, Andrea; Strachan, Clare; Gordon, Keith C.; Yliruusi, Jouko; Rades, Thomas; Sandler, Niklas.

In: European Journal of Pharmaceutical Sciences, Vol. 30, No. 2, 2007, p. 113-123.

Research output: Contribution to journalJournal articlepeer-review

Harvard

Savolainen, M, Heinz, A, Strachan, C, Gordon, KC, Yliruusi, J, Rades, T & Sandler, N 2007, 'Screening for differences in the amorphous state of indomethacin using multivariate visualization', European Journal of Pharmaceutical Sciences, vol. 30, no. 2, pp. 113-123. https://doi.org/10.1016/j.ejps.2006.10.010

APA

Savolainen, M., Heinz, A., Strachan, C., Gordon, K. C., Yliruusi, J., Rades, T., & Sandler, N. (2007). Screening for differences in the amorphous state of indomethacin using multivariate visualization. European Journal of Pharmaceutical Sciences, 30(2), 113-123. https://doi.org/10.1016/j.ejps.2006.10.010

Vancouver

Savolainen M, Heinz A, Strachan C, Gordon KC, Yliruusi J, Rades T et al. Screening for differences in the amorphous state of indomethacin using multivariate visualization. European Journal of Pharmaceutical Sciences. 2007;30(2):113-123. https://doi.org/10.1016/j.ejps.2006.10.010

Author

Savolainen, Marja ; Heinz, Andrea ; Strachan, Clare ; Gordon, Keith C. ; Yliruusi, Jouko ; Rades, Thomas ; Sandler, Niklas. / Screening for differences in the amorphous state of indomethacin using multivariate visualization. In: European Journal of Pharmaceutical Sciences. 2007 ; Vol. 30, No. 2. pp. 113-123.

Bibtex

@article{a97112c5199346449567f2fee9496049,
title = "Screening for differences in the amorphous state of indomethacin using multivariate visualization",
abstract = "The aim of this study was to examine molecular-level differences in the amorphous state of indomethacin prepared from both alpha- and gamma-polymorphs using various preparative techniques: milling, quench cooling of a melt, slow cooling of a melt and spray drying. X-ray powder diffraction (XRPD), polarizing light microscopy (PLM), differential scanning calorimetry, as well as mid-infrared (MIR), near infrared (NIR) and Raman spectroscopy were used to analyze the samples after preparation. Principal component analysis (PCA) was used to visualize the differences in the spectroscopic data. According to the XRPD and PLM measurements, all samples except the spray dried indomethacin were amorphous after preparation. Spray dried indomethacin had some remaining residual crystallinity. Differences in the amorphous samples could be found on molecular level: the milled samples clustered separately from the other amorphous samples in the PCA of MIR, NIR and Raman spectra. This could be due to either small degrees of undetected crystallinity remaining in the samples after milling or differences in the hydrogen bonding in the different amorphous samples of indomethacin. The spectroscopic techniques revealed different information about the samples. Raman spectroscopy was most sensitive to differences caused by the preparation techniques and degradation products. Multivariate methods, such as PCA, offer an efficient tool to screen for these differences in the amorphous state.",
keywords = "indomethacin, amorphous state, principal component analysis, spectroscopic techniques",
author = "Marja Savolainen and Andrea Heinz and Clare Strachan and Gordon, {Keith C.} and Jouko Yliruusi and Thomas Rades and Niklas Sandler",
year = "2007",
doi = "10.1016/j.ejps.2006.10.010",
language = "English",
volume = "30",
pages = "113--123",
journal = "Norvegica Pharmaceutica Acta",
issn = "0928-0987",
publisher = "Elsevier",
number = "2",

}

RIS

TY - JOUR

T1 - Screening for differences in the amorphous state of indomethacin using multivariate visualization

AU - Savolainen, Marja

AU - Heinz, Andrea

AU - Strachan, Clare

AU - Gordon, Keith C.

AU - Yliruusi, Jouko

AU - Rades, Thomas

AU - Sandler, Niklas

PY - 2007

Y1 - 2007

N2 - The aim of this study was to examine molecular-level differences in the amorphous state of indomethacin prepared from both alpha- and gamma-polymorphs using various preparative techniques: milling, quench cooling of a melt, slow cooling of a melt and spray drying. X-ray powder diffraction (XRPD), polarizing light microscopy (PLM), differential scanning calorimetry, as well as mid-infrared (MIR), near infrared (NIR) and Raman spectroscopy were used to analyze the samples after preparation. Principal component analysis (PCA) was used to visualize the differences in the spectroscopic data. According to the XRPD and PLM measurements, all samples except the spray dried indomethacin were amorphous after preparation. Spray dried indomethacin had some remaining residual crystallinity. Differences in the amorphous samples could be found on molecular level: the milled samples clustered separately from the other amorphous samples in the PCA of MIR, NIR and Raman spectra. This could be due to either small degrees of undetected crystallinity remaining in the samples after milling or differences in the hydrogen bonding in the different amorphous samples of indomethacin. The spectroscopic techniques revealed different information about the samples. Raman spectroscopy was most sensitive to differences caused by the preparation techniques and degradation products. Multivariate methods, such as PCA, offer an efficient tool to screen for these differences in the amorphous state.

AB - The aim of this study was to examine molecular-level differences in the amorphous state of indomethacin prepared from both alpha- and gamma-polymorphs using various preparative techniques: milling, quench cooling of a melt, slow cooling of a melt and spray drying. X-ray powder diffraction (XRPD), polarizing light microscopy (PLM), differential scanning calorimetry, as well as mid-infrared (MIR), near infrared (NIR) and Raman spectroscopy were used to analyze the samples after preparation. Principal component analysis (PCA) was used to visualize the differences in the spectroscopic data. According to the XRPD and PLM measurements, all samples except the spray dried indomethacin were amorphous after preparation. Spray dried indomethacin had some remaining residual crystallinity. Differences in the amorphous samples could be found on molecular level: the milled samples clustered separately from the other amorphous samples in the PCA of MIR, NIR and Raman spectra. This could be due to either small degrees of undetected crystallinity remaining in the samples after milling or differences in the hydrogen bonding in the different amorphous samples of indomethacin. The spectroscopic techniques revealed different information about the samples. Raman spectroscopy was most sensitive to differences caused by the preparation techniques and degradation products. Multivariate methods, such as PCA, offer an efficient tool to screen for these differences in the amorphous state.

KW - indomethacin

KW - amorphous state

KW - principal component analysis

KW - spectroscopic techniques

U2 - 10.1016/j.ejps.2006.10.010

DO - 10.1016/j.ejps.2006.10.010

M3 - Journal article

C2 - 17169536

VL - 30

SP - 113

EP - 123

JO - Norvegica Pharmaceutica Acta

JF - Norvegica Pharmaceutica Acta

SN - 0928-0987

IS - 2

ER -

ID: 40357231