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Chiral Purity in Drug Analysis

Pharmaceuticals and Drugs

  1. Yoshio Machida,
  2. Hiroyuki Nishi

Published Online: 15 SEP 2006

DOI: 10.1002/9780470027318.a1906

Encyclopedia of Analytical Chemistry

Encyclopedia of Analytical Chemistry

How to Cite

Machida, Y. and Nishi, H. 2006. Chiral Purity in Drug Analysis. Encyclopedia of Analytical Chemistry. .

Author Information

  1. Tanabe Seiyaku, Co. Ltd, Osaka, Japan

Publication History

  1. Published Online: 15 SEP 2006


The preparation and evaluation of optically active compounds have become very important for the development of new drugs. The determination of chiral purity of drugs is essential in order to guarantee safety and effectiveness. Isomeric impurities may have unwanted toxicological, pharmacological, or other side-effects. Therefore we decided to prepare an article entitled “Chiral purity in drug analysis”. This article is divided into five sections (introduction, production, regulation, evaluation methods and conclusion). In the introduction, the importance of assessing the isomeric impurities in drug analysis will be discussed. In the second section, production methods for optically active compounds, except the stereoselective synthesis method, will be summarized briefly. In particular, new trends in the production of chiral drugs, such as the simulated moving beds (SMB) method, will be described. In the third section, regulatory perspectives in the USA (Food and Drug Administration (FDA)), EC, and Japan will be described and some regulatory guidelines and guidances by, for example, the FDA, the Committee for Veterinary Medicinal Products (CVMP), and the International Conference on Harmonization (ICH) will be mentioned. In the fourth section, methods for the determination of stereoisomeric drugs will be summarized. Methods such as gas chromatography (GC), high-performance liquid chromatography (HPLC), and capillary electrophoresis (CE) have been summarized. The focus will be on direct evaluation methods, i.e. those using chiral stationary phases (CSPs). Practical details for testing a drug's optical purity are also given.