To establish an HPLC method for the determination of the related substances in telmisartan.
Waters Symmetry Shield RP8 (150 mm×4.6 mm, 3.5 μm) column was adopted. The mobile phase A was 0.1% phosphoric acid solution (pH was adjusted to 3.0 with triethylamine), and the mobile phase B was acetonitrile. The gradient elution was performed. The flow rate, column temperature and wavelength were 0.8 mL·min-1, 25 ℃ and 230 nm, respectively.
The resolutions between the peaks of telmisartan and nine known impurities were greater than 1.5. The limits of quantitation of all impurities were less than 40 ng·mL-1, and the limits of detection of all impurities were less than 10 ng·mL-1. The standard curves of telmisartan and its impurities were linear within the range 30-600 ng·mL-1, and the correlation coefficients were all greater than 0.999 5. The average recovery rates of impurities Ⅰ-Ⅸ were 93.8%, 99.8%, 97.5%, 99.2%, 99.8%, 98.3%, 98.4%, 99.2% and 99.7%, respectively, and the RSDs of 9 results were all less than 2.0%. Changing the flow rate, column temperature, wavelength, mobile phase ratio and pH did not affect the detection results of the related substances. The results of maximum single impurity were 0.02% in three batches of telmisartan, and the results of total impurities were less than 0.10%.
The method is highly specific, sensitive, precise and accurate, and can be used for the determination of related substances of telmisartan.
| 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 |