Biotechnology and Bioprocess Engineering 2020; 25(1): 86-93  
Removal of Residual Toluene and Methyl Tertiary Butyl Ether from Amorphous Paclitaxel by Simple Rotary Evaporation with Alcohol Pretreatment
Hoe-Jong Kang and Jin-Hyun Kim
Department of Chemical Engineering, Kongju National University, Cheonan 31080, Korea
Correspondence to: Jin-Hyun Kim*
Department of Chemical Engineering, Kongju National University, Cheonan 31080, Korea
Tel: +82-41-521-9361; Fax: +82-41-554-2640
Received: August 25, 2019; Revised: September 25, 2019; Accepted: October 4, 2019; Published online: February 29, 2020.
© The Korean Society for Biotechnology and Bioengineering. All rights reserved.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
In this study, a drying method was developed for effective removal of residual solvents from toluene- or methyl tertiary butyl ether-induced amorphous paclitaxel. By simple rotary evaporation with alcohol pretreatment, there was sufficient removal of the residual toluene, methyl tertiary butyl ether, methanol, and ethanol concentrations of paclitaxel to bring them below the ICH-specified values (890, 5000, 3,000, and 5,000 ppm). In addition, SEM analysis and ultrasonic treatment revealed that residual solvent removal was associated with the formation of pores on the surface of the sample because of the high vapor pressure of the toluene-alcohol mixture or the methyl tertiary butyl ether-alcohol mixture and hydrogen bonding between the solvent and the alcohol.
Keywords: amorphous paclitaxel, residual solvent, removal, pretreatment with alcohol, drying

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