Article

Quantitative determination of famotidine polymorphs: X-ray powder diffractometric and Raman spectrometric study.

Drug Polymorphism Research Division, Gedeon Richter Plc., H-1475 Budapest, Hungary.
Journal of Pharmaceutical and Biomedical Analysis (impact factor: 2.97). 01/2009; 49(2):338-46. DOI:10.1016/j.jpba.2008.11.033 pp.338-46
Source: PubMed

ABSTRACT X-ray powder diffractometric and Raman spectrometric methods were developed for quantitative measurement of the polymorphic forms of famotidine in their mixtures. This study aims to deduce some useful conclusions regarding quantitative polymorph analysis, which could also be utilized in industrial practice. Both form A and form B of famotidine possess specific X-ray diffraction reflections as well as characteristic Raman vibrational bands, which permits simple determination of the phases in their mixtures. Keeping in mind that multivariate data processing by chemometric approach is thought of nowadays as superior over univariate one, the results of the two evaluation methods were compared by precision, accuracy as well as robustness. It was found that both approaches provide similar results provided analytically useful data regions are properly selected. Overcoming the common problems of quantitative X-ray powder diffractometry and solid state Raman spectrometry both permit accurate quantification of famotidine polymorphs; the latter, however, seems to be more favourable in regular laboratory practice.

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    Article: A powder X-ray diffraction method for detection of polyprenylated benzophenones in plant extracts associated with HPLC for quantitative analysis.
    Felipe T Martins, Marcelo H dos Santos, Carla P Coelho, Luiz C A Barbosa, Gizelly C Dias, Mônica P Fracca, Person P Neves, Paulo C Stringheta, Antônio C Doriguetto
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    Journal of pharmaceutical and biomedical analysis 09/2010; 54(3):451-7. · 2.45 Impact Factor
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Keywords

approaches
 
characteristic Raman vibrational bands
 
common problems
 
deduce
 
industrial practice
 
mixtures
 
multivariate data processing
 
permits simple determination
 
polymorphic forms
 
quantitative X-ray powder diffractometry
 
Raman spectrometric methods
 
regular laboratory practice
 
solid state Raman spectrometry
 
specific X-ray diffraction reflections
 
superior
 
two evaluation methods
 
univariate
 
X-ray powder diffractometric