Related Experiment Videos
Chemical hydrolysis of DOTAP and DOPE in a liposomal environment
E A A M Vernooij1, J J Kettenes-van den Bosch, W J M Underberg
1Department of Pharmaceutics, Faculty of Pharmacy, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, P.O. Box 80 082, 3508 TB, Utrecht, The Netherlands.
Abstract:
In this study the hydrolysis kinetics of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) and 1,2-dioleoyltrimethylammoniumpropane (DOTAP) in net neutral DPPC-DOPE (3:1, mol/mol) and cationic DOTAP-DOPE (1:1, mol/mol) liposomes are described. The log k(obs)-pH profile for DOTAP-DOPE liposomes differs markedly from earlier observed hydrolysis profiles: the slope approaches zero in the acidic region and +1 in the alkaline region. The concept of amine-influenced hydrolysis is introduced to explain the lack of pH dependency in the acidic region of the log k(obs)-pH profiles.