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arXiv · 1901.00728

Paracetamol Micro-Structure Analysis by Optical Mapping

Reo Honda·Meguya Ryu·Armandas Balcytis·Jitraporn Vongsvivut·Mark J. Tobin·Saulius Juodkazis·Junko Morikawa
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Abstract

Domain structure of paracetamol -- popular antipyretic analgesic -- was investigated by infrared (IR) spectroscopy using synchrotron radiation. Absorbance and retardance maps reveal molecular orientation inside the micro-domains of the paracetamol form II which has a better water solubility and compressibility compared to the commercially used forms I. The developed method of analysis representing orientation of optical slow(fast)-axis is compared with azimuthal orientation of the absorbance at several specific IR bands using vector maps. High brightness of synchrotron radiation and hyper-spectral mapping of structural domains in paracetamol clearly reveals the domain boundaries and can potentially be used to observe \emph{in situ} intra-phase transformations of paracetamol forms-I, II, III and melting, which are important for making medical tablets and powders by an industrial process.

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Reo Honda, Meguya Ryu, Armandas Balcytis, Jitraporn Vongsvivut, Mark J. Tobin, Saulius Juodkazis, Junko Morikawa. 2018-12-24. Paracetamol Micro-Structure Analysis by Optical Mapping. https://doi.org/10.1016/j.apsusc.2018.12.121

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