ABSTRACT
Objective:To analyze the related substances in the domestic products of minoxidil and minoxidil gel for the purpose of standard improvement. Methods:An HPLC-Q-TOF-MS method was developed. The test was performed on a Thermo Scientific Accu-core C18 column (100 mm × 2. 1 mm, 2. 6 μm) with a mobile phase of acetonitrile-water (7:93) (containing 0. 1% formic acid) at a flow rate of 0. 2 ml·min-1 , the detection wavelength was 230 nm. The full scan and two stage scanning was employed for detection with ESI source positive ion mode. The mass scan range was m/z 50-500. Results:14 related substances were separated and detected under the established HPLC-Q-TOF-MS condition. The structures and resource of 8 related substances were analyzed preliminarily. Conclusion:The HPLC-Q-TOF-MS technology has been proved to be effective in separation and identification of the related substances in minoxidil and minoxidil gel. The results were useful for quality control.
ABSTRACT
OBJECTIVE: To elucidate the structure of the major impurity in gemcitabine hydrochloride for injection. METHODS: HPLC-QTOF-MS was adopted to analyze the structure of this impurity based on the fragmentation behavior of gemcitabine and this impurity. The separation was performed on a ZORBAX Eclipse XDB-C18(4.6 mm×250 mm, 5 μm) column. A mixture of 10% methanol and 90% 10 mmol·L-1 ammonium acetate(pH 5.7) was used as mobile phase. Flow rate was 1.0 mL·min-1. MS was performed under positive mode with 4.0 kV capillary voltage, 65 V skimmer, 310 kPa spray pressure, 11 L·min-1 drying gas (nitrogen) flow rate, 350°C drying gas temperature and 150 V fragmentor. CONCLUSION: This study offers scientific data for studying the origin of the impurity of gemcitabine hydrochloride and improving its quality.