1. Department of Chemistry University of Fort Hare, Alice Campus, Alice Eastern Cape South Africa
2. School of Pharmacy University of the Western Cape, Bellville Cape Town 7535 South Africa
3. School of Chemistry, Mass Spectrometry division University of Witwatersrand Johannesburg South Africa
4. Department of Chemistry University of Johannesburg, Auckland Park Campus Johannesburg South Africa
5. Department of Applied Chemistry University of Johannesburg, Doornfontein Campus Johannesburg South Africa
6. Department of Biochemistry, Microbiology and Biotechnology, Faculty of Science and Agriculture University of Limpopo Limpopo South Africa