著者

Nahoko Uchiyama Junko Hosoe Naoki Sugimoto Kyoko Ishizuki Tatsuo Koide Mika Murabayashi Naoto Miyashita Kengo Kobayashi Yoshinori Fujimine Toshiyuki Yokose Katsuya Ofuji Hitoshi Shimizu Takashi Hasebe Yumi Asai Eri Ena Junko Kikuchi Kohei Kiyota Kazuhiro Fujita Yoshinobu Makino Naoko Yasobu Yoshiaki Iwamoto Toru Miura Koji Mizui Katsuo Asakura Takako Suematsu Hitomi Muto Ai Kohama Takashi Goto Masu Yasuda Tomohiko Ueda Yukihiro Goda

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.69, no.7, pp.630-638, 2021-07-01 (Released:2021-07-01)

参考文献数

22

被引用文献数

5

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Recently, quantitative NMR (qNMR), especially 1H-qNMR, has been widely used to determine the absolute quantitative value of organic molecules. We previously reported an optimal and reproducible sample preparation method for 1H-qNMR. In the present study, we focused on a 31P-qNMR absolute determination method. An organophosphorus compound, cyclophosphamide hydrate (CP), listed in the Japanese Pharmacopeia 17th edition was selected as the target compound, and the 31P-qNMR and 1H-qNMR results were compared under three conditions with potassium dihydrogen phosphate (KH2PO4) or O-phosphorylethanolamine (PEA) as the reference standard for 31P-qNMR and sodium 4,4-dimethyl-4-silapentanesulfonate-d6 (DSS-d6) as the standard for 1H-qNMR. Condition 1: separate sample containing CP and KH2PO4 for 31P-qNMR or CP and DSS-d6 for 1H-qNMR. Condition 2: mixed sample containing CP, DSS-d6, and KH2PO4. Condition 3: mixed sample containing CP, DSS-d6, and PEA. As conditions 1 and 3 provided good results, validation studies at multiple laboratories were further conducted. The purities of CP determined under condition 1 by 1H-qNMR at 11 laboratories and 31P-qNMR at 10 laboratories were 99.76 ± 0.43 and 99.75 ± 0.53%, respectively, and those determined under condition 3 at five laboratories were 99.66 ± 0.08 and 99.61 ± 0.53%, respectively. These data suggested that the CP purities determined by 31P-qNMR are in good agreement with those determined by the established 1H-qNMR method. Since the 31P-qNMR signals are less complicated than the 1H-qNMR signals, 31P-qNMR would be useful for the absolute quantification of compounds that do not have a simple and separate 1H-qNMR signal, such as a singlet or doublet, although further investigation with other compounds is needed.

著者

Nahoko Uchiyama Junko Hosoe Naoki Sugimoto Kyoko Ishizuki Tatsuo Koide Mika Murabayashi Naoto Miyashita Kengo Kobayashi Yoshinori Fujimine Toshiyuki Yokose Katsuya Ofuji Hitoshi Shimizu Takashi Hasebe Yumi Asai Eri Ena Junko Kikuchi Kohei Kiyota Kazuhiro Fujita Yoshinobu Makino Naoko Yasobu Yuko Yamada Yoshiaki Iwamoto Toru Miura Koji Mizui Katsuo Asakura Takako Suematsu Ai Kohama Yukihiro Goda

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.69, no.1, pp.118-123, 2021-01-01 (Released:2021-01-01)

参考文献数

11

被引用文献数

10

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Quantitative NMR (qNMR) is applied to determine the absolute quantitative value of analytical standards for HPLC-based quantification. We have previously reported the optimal and reproducible sample preparation method for qNMR of hygroscopic reagents, such as saikosaponin a, which is used as an analytical standard in the assay of crude drug section of Japanese Pharmacopoeia (JP). In this study, we examined the absolute purity determination of a hygroscopic substance, indocyanine green (ICG), listed in the Japanese Pharmaceutical Codex 2002, using qNMR for standardization by focusing on the adaptation of ICG to JP. The purity of ICG, as an official non-Pharmacopoeial reference standard (non-PRS), had high variation (86.12 ± 2.70%) when preparing qNMR samples under non-controlled humidity (a conventional method). Additionally, residual ethanol (0.26 ± 0.11%) was observed in the non-PRS ICG. Next, the purity of non-PRS ICG was determined via qNMR when preparing samples under controlled humidity using a saturated sodium bromide solution. The purity was 84.19 ± 0.47% with a lower variation than that under non-controlled humidity. Moreover, ethanol signal almost disappeared. We estimated that residual ethanol in non-PRS ICG was replaced with water under controlled humidity. Subsequently, qNMR analysis was performed when preparing samples under controlled humidity in a constant temperature and humidity box. It showed excellent results with the lowest variation (82.26 ± 0.19%). As the use of a constant temperature and humidity box resulted in the lowest variability, it is recommended to use the control box if the reference ICG standard is needed for JP assays.

著者

Yusai Ito Naoki Harikai Kyoko Ishizuki Kazufusa Shinomiya Naoki Sugimoto Hiroshi Akiyama

出版者

公益社団法人日本薬学会

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

pp.c17-00404, (Released:2017-07-01)

参考文献数

18

被引用文献数

4

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Cochineal extract prepared from the scale insect Dactylopus coccus (American cochineal) has been used as a natural red dye for food, cosmetics, and pharmaceuticals. The major pigment in cochineal extract is carminic acid (CA), an anthraquinone glucoside, and several minor pigments have been previously reported. Our investigation aimed at establishing the safety of cochineal dye products using UPLC-PDA-ESI-TOF/MS found an unknown minor pigment, spiroketalcarminic acid (1), in three commercial cochineal extract samples; cochineal extract used in food additives, carmine that is an aluminum salt of cochineal extract used as natural dye, and a research reagent of CA. The purification of 1 from cochineal extract involved sequential chromatographic techniques, including preparative reversed-phase HPLC. 2D NMR and mass analyses established the structure of 1 to be a novel anthraquinone with an unusual 6,5-spiroketal system instead of the C-glucosyl moiety of CA. The absolute stereochemistry of the spiroketal moiety in 1 was determined by NOESY correlations and optical rotation. No data corresponding to 1 had previously been reported for extracts of dried cochineal insects and traditional art products dyed with cochineal extract, indicating that 1 is likely produced during the preparation of commercial cochineal extract.