Related Experiment Video
Updated: Jan 20, 2026
Glovebox-Operating Procedure and Use of Impurity Sensors
Published on: April 29, 2023
[Enantiomeric separation and impurity determination of valaciclovir hydrochloride]
Qian-ying Zhu1, Lu-shan Yu1, Guo-gang Zheng2
1Laboratory of Pharmaceutical Analysis and Drug Metabalism, College of Pharmaceutical Sciences; Zhejiang Provincial Key Laboratory of Anti-Cancer Drug Research, Zhejiang University, Hangzhou 310058, China.
Objective:
To determine the contents of L-enantiomer impurity in valaciclovir hydrochloride.
Methods:
Valaciclovir enantiomers were separated and determined by using chiral high performance liquid chromatography. Chromatographic conditions were as follows:CROWNPAK(®) CR(+) chiral column (4 mm×150 mm, 5 μm), detection wavelength:254 nm, mobile phase:water-methanol-perchloric acid (19:1:0.1), flow rate:0.75 ml/min, sample injection volume:10 μl.
Results:
D-valaciclovir was completely separated from L-enantiomer impurity. The contents of L-enantiomer impurity were 0.65%-2.62% on average in 8 batches of valaciclovir hydrochloride.
Conclusion:
Enantiomeric impurity contents in each batch of products were all meet criteria of United States Pharmacopeia, which can be used in criteria of Chinese Pharmacopeia as references.
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