Determination of enantiomeric impurity of timolol maleate in bulk substances and eye drops.
- Author:
Qian-ying ZHU
1
,
2
;
Lu-shan YU
1
;
Guo-gang ZHENG
3
;
Shen-gu XIE
3
;
Qiao-feng TAO
3
;
Author Information
- Publication Type:Journal Article
- MeSH: Chromatography, High Pressure Liquid; methods; Drug Contamination; Ophthalmic Solutions; analysis; standards; Stereoisomerism; Timolol; analysis; standards
- From: Journal of Zhejiang University. Medical sciences 2014;43(2):160-163
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo determine the enantiomeric impurity contents of domestic timolol maleate in bulk drugs and eye drops.
METHODSEnantiomer impurity of timolol was assayed by chiral high performance liquid chromatography. The chromatographic conditions were as follows:chiralcel OD chiral column (4.6 mm ×150 mm, 5μm), detection wavelength:297 nm, mobile phase:hexane-isopropanol-diethylamine (480:20:1), column temperature:25 ℃, flow rate:1.0 ml/min, sample injection volume:5 μl.
RESULTSThe resolution between R- and S-timolol was more than 4. The enantiomeric impurity contents were less than 0.67% on average in two batches of timolol maleate bulk drugs, and 0.31% on average in three batches of timolol maleate eye drops.
CONCLUSIONEnantiomeric impurity contents in each batch of products all meet European Pharmacopoeia criteria, which can be used as references in Chinese Pharmacopoeia criteria.
