Shandong Shenlian Pharmaceutical Co., Ltd.

Objective To determine ralated Substances in pramipexole hydrochloride by HPLC.Methods: The Agilent ZORBAX SB-C18 column (4.6 × 150 mm, 5 μm) was adopted and the column temperature was set at 35°C.The mobile phase A (pH 3.0 buffer) andmobile phase B (pH 3.0 buffer: acetonitrile (30: 70) was eluted by mobile phase gradient, The flow rate was at 1.5 mL·min^-1.The detection wavelength was 264 nm.Results Known impurities were completely separated from the main constituent and the impurities can be accurately quantified.Pramipexole hydrochloride, (2-nitrophenyl) thio acetic acid, Impurity A and Impurity B showed a good linearity in the ranges of 0.007185 ∼ 1.724, 0.09020 ∼ 0.5412, 0.09184 ∼ 2.755, 0.08432 ∼ 2.529 μg·mL^-1 (r>0.999).The average recoveries of (2-nitrophenyl) thio acetic acid, Impurity A and Impurity B (n=9) were 99.1%, 101.5% and 98.2%, RSD was 1.5%, 2.1% and 1.2% resp.Conclusion The method is simple and accurate and can be used as a method for determination of related substances in pramipexole hydrochloride.

To determine ralated Substances in milrinone by HPLC.The Waters C8 column (4.6 × 250 mm, 5 μm) was adopted and the column temperature was set at 35°C, the mixture of dipotassium hydrogen phosphate solution-acetonitrile (80: 20) was used as the mobile phase and the flow rate was 1.0 mL·min^-1, and the detection wavelength was 254 nm.Known impurities were completely separated from the main constituent, and the impurities can be accurately quantified.The calibration curves were linear within the concentration rang of 0.199 ∼ 3.978 μg·mL^-1 (r=0.9997) for milrinone and 0.201 ∼ 4.024 μg·mL^-1 (r=0.9999) for milrinone impurity A.The average recoveries for milrinone impurity A was 100.1% (RSD=0.74%, n=9).The method is simple and accurate and can be used as a method for determination of related substances in milrinone.

Objective To establish a gas chromatog. method for the determination of residual solvent of naphazoline Hydrochloride API.Methods Gas chromatog. was performed on a capillary column with polyethylene glycol as the fixed solution, the size of which was 30 m×0.32 mm×0.5μm.The temperature was programmed: the initial temperature was 50°C, maintained for 13 min, and the temperature was raised to 200°C at a rate of 20°C/min, maintained for 3 min.Inlet temperature: 200°C; FID detector temperature: 250°C; Balance temperature of headspace bottle: 90°C, balance time: 30 min; Shunt ratio: 35:1; Carrier gas: Nitrogen; Average linear speed: 20 cm/s.Results Under the selected conditions, there is no interference in the blank and the separation degree of each residual solvent peak is good.The linear relationship of Et ether, acetone, Et acetate, methanol, isopropanol, ethanol and benzene was good in the concentration range of LOQ∼150%.The LOD were 0.26×10^-3, 0.0124, 8.01×10^-3, 0.227, 0.05, 0.128, 3.16×10^-3 μg/mL, resp.The LOQ were 0.519×10^-3, 0.0373, 0.0267, 0.682, 0.149, 0.255, 9.49×10^-3 μg/mL, resp.The results of reproducibility and recovery were good.Conclusion: The method is exclusive, accurate and easy to operate.It is suitable for the determination of residual solvent of naphazoline hydrochloride.