1. Department of Chemical Sciences Formerly known as the Department of Applied
Chemistry, University of Johannesburg, Doornfontein 2028, South Africa
2. Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
3. Groningen Institute of Pharmacy, Pharmaceutical Analysis, The University of Groningen, P.O. Box 196, AD Groningen 9700, The Netherlands
4. Centre for Nanomaterials Science Research, University of Johannesburg, Doornfontein 2028, Johannesburg, South Africa