To establish a quantitative fluorine nuclear magnetic resonance (qFNMR) method for the determination the content of reference standards of moxifloxacin hydrochloride and its three impurities.
The fluorine nuclear magnetic resonance spectra of the reference standards of moxifloxacin hydrochloride and its three impurities (Impurity Ⅰ, Impurity Ⅲ, and Impurity Ⅳ) were collected using a Bruker Avance NEO 600 MHz spectrometer with 4,4′-difluorobenzophenone as the internal standard and DMSO-d6 as the solvent. The spectra were acquired with the zgig pulse program, 32 scans (NS), an acquisition time of 2.88 s, and a relaxation delay time (D1) of 10 s, and quantitative analysis was performed.
The quantitative peaks of moxifloxacin hydrochloride and its three impurities were well separated from that of the internal standard 4,4′-difluorobenzophenone on the fluorine NMR spectra. Good linear relationships were obtained for moxifloxacin hydrochloride, Impurity Ⅰ, Impurity Ⅲ and Impurity Ⅳ in the ranges of 2.988~14.70, 3.012~15.17, 3.149~15.26, 2.857~14.58 mg·mL-1, respectively (r>0.999 4). The precision and repeatability of the method were good. The content results determined by the qFNMR method were basically consistent with those obtained from the mass balance method.
The established qFNMR method for the content determination of reference standards of moxifloxacin hydrochloride and its three impurities is simple, rapid, and highly accurate, thus providing a reference for the establishment and content determination of these reference standards.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |