Organic Process Research & Development
ARTICLE
approaches was demonstrated herein to be effective for generat-
ing better process understanding of the acetic anhydride model
reaction during process development. The similarities and
differences in spectroscopic measurements (immersion and
noncontact optics), data processing (cosmic ray aberrations
removal, accounting for spectral anormalies and glass vessel
background, and sapphire crystal of probe), multivariate analysis
’ ACKNOWLEDGMENT
The authors would like to express gratitude to the Institute of
Chemical and Engineering Sciences (ICES) for research funding
support through an industrial collobration project ICES/
0
6-330B01 with National Instruments. The cosmic ray unspiking
35
algorithm employed herein was developed through the same
industrial project. The authors also thank Professor Brian Cox of
AstraZenaca for his invaluable input for developing the dissolu-
tion-reaction kinetics model and related numerical optimization.
(curve resolution and data regression), use of different reaction
volumes in varied glass reactors, and their estimated kinetics
modeling parameters (pseudo-first-order reaction, Arrhenius
theory, and dissolution-reaction kinetics) were studied and
discussed.
’
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’
AUTHOR INFORMATION
Corresponding Author
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19) Garcia, T.; Cook, G.; Nosal, R. J. Pharm. Innov. 2008, 3, 60.
*Phone: (65) 6796 3961. Fax: (65) 6316 6185. E-mail: chew_wee@
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and Implementation Strategies for the Chemical and Pharmaceutical
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dx.doi.org/10.1021/op100337v |Org. Process Res. Dev. 2011, 15, 610–621