Tebello Nyokong1, Bokolombe P Ngoy2, Edith K Amuhaya3. 1. Institute for Nanotechnology Innovation, Rhodes University, Makhanda, South Africa. t.nyokong@ru.ac.za. 2. Département de Chimie, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo. 3. School of Pharmacy and Health Sciences, United States International University - Africa, Nairobi, Kenya.