1. Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, P. O. Box 80082, 3508 TB Utrecht, The Netherlands, Department of Medicinal Chemistry, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, P. O. Box 80082, 3508 TB Utrecht, The Netherlands, and Department of Polymer Chemistry and Biomaterials and Institute for Biomedical Technology, Faculty of Science and Technology, University of Twente, P. O. Box 217, 7500 AE, Enschede, The...