1. Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2, Canada
2. National Institute for Nanotechnology, National Research Council Canada, 11421 Saskatchewan Drive, Edmonton, AB T6G 2M9, Canada
3. Department of Pharmaceutical Chemistry, College of Health Sciences, University of Ghana School of Pharmacy, P.O. Box LG 43, Legon, Ghana