An LC-MS method with natural isotope abundance correction and a 1H NMR relative quantitative method were established to determine the deuterium incorporation of donafenib tosilate, a new deuterated drug molecule. First, the peak areas of isotopic impurities (non-deuterated and incompletely deuterated impurities) and deuterated drug were recorded through the single ion monitoring (SIM) mode of the established LC-MS method and then corrected in terms of the natural isotope abundance offered by ChemDraw soft, removing the nature isotope interference from 13C, 37Cl, etc. The corrected areas were subsequently used to calculate mol% of isotopologues (D0, D1, D2, D3) and Atom% D, namely, deuterium incorporation. In addition, a 1H qNMR experiment was conducted with the aromatic proton at δ 8.63 and the residual proton of isotopic impurities at δ 2.79 as quantitative peaks. The mixture of DMSO-d6 and D2O (10∶1) was employed as the solvent to change the spin-coupling between the residual proton and active hydrogen so that the residual proton could be measured as the single peak, and the sensitivity was greatly improved. The acquisition parameters were also optimized, and Atom% 1H and the deuterium incorporation were then calculated. The two methods were applied to samples of three commercial batches, and the testing results were almost consistent. Both methods proved accurate, sensitive, fast and independent of standard substances and accurate weighing, which could be applied to the determination of the deuterium incorporation of donafenib tosilate and provide a reference for other deuterated drugs.
| 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 |