Luźnik Janko, Pirnat Janez, Jazbinšek Vojko, Lavrič Zoran, Žagar Veselko, Srčič Stane, Seliger Janez, Trontelj Zvonko
Institute of Mathematics, Physics and Mechanics, Ljubljana, Slovenia.
Institute of Mathematics, Physics and Mechanics, Ljubljana, Slovenia.
J Pharm Sci. 2014 Sep;103(9):2704-2709. doi: 10.1002/jps.23956. Epub 2014 Mar 25.
(14)N nuclear quadrupole resonance (NQR) in two known polymorphs of famotidine was measured. At room temperature, seven quadrupolar sets of transition frequencies (ν(+), ν(-), and ν(0)) corresponding to seven different nitrogen sites in the crystal structure of each of the two polymorphs were found. This confirms the expected ability of NQR to distinguish polymorph B from its analog A. NQR can also measure their ratio in a solid mixture and in the final dosage form, that is, a tablet. The NQR frequencies, line shapes, and tentative assignation to all seven molecular (14)N atoms were obtained. Unravelment of these two entangled NQR spectra presents a valuable contribution to the NQR database and enables studies of some possible correlations therein. Moreover, nondestructive (14)N NQR studies of commercial famotidine tablets can reveal some details of the drug fabrication process connected with compression.
（14）测定了法莫替丁两种已知多晶型物中的氮核四极共振（NQR）。在室温下，发现了与两种多晶型物中每一种的晶体结构里七个不同氮位点相对应的七组四极跃迁频率（ν(+)、ν(-)和ν(0)）。这证实了NQR区分多晶型物B与其类似物A的预期能力。NQR还可以测量它们在固体混合物和最终剂型（即片剂）中的比例。获得了NQR频率、线形以及对所有七个分子（14）N原子的初步归属。解开这两个纠缠的NQR光谱对NQR数据库做出了有价值的贡献，并有助于研究其中一些可能的相关性。此外，对市售法莫替丁片剂进行无损（14）N NQR研究可以揭示与压片相关的药物制造过程的一些细节。
