Analysis of small molecule drugs, excipients and counter ions in pharmaceuticals by capillary electromigration methods – recent developments
Capillary electromigration techniques have become important tools for the analysis of pharmaceutical drugs. The present review updates on recent developments of the analysis of small molecule drugs, excipients and counter ions dating between January 2014 and May 2017. Capillary electrophoresis (CE) continues to be a very popular method for the analysis of the active pharmaceutical ingredients and their related substances in pharmaceutical formulations, especially for the determination of the stereoisomeric purity of chiral drugs, which is evidenced by a large number of related literature reported in the reviewed period of time. The simultaneous analysis of several drugs has been easily achieved by CE. Moreover, the flexibility of the technique has been clearly illustrated by the application of various separation modes including capillary zone electrophoresis, isotachophoresis as well as various modes of electrokinetic chromatography such as micellar electrokinetic chromatography or microemulsion electrokinetic chromatography in combination with various detection modes including direct and indirect UV, laser-induced fluorescence, mass spectrometry and contactless conductivity detection. A general trend also observed in other analytical techniques is the application of quality by design principles in CE.