1. Department of Science and Innovation/Mintek Nanotechnology Innovation Centre, Department of Biotechnology, Faculty of Natural Sciences, University of the Western Cape, Bellville, South Africa;
2. Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa;
3. Department of Biotechnology, Faculty of Natural Sciences, University of the Western Cape, Bellville, South Africa;
4. Nanobiotechnology Research Group, Department of Biotechnology, Faculty of Natural Sciences, University of the Western Cape, Bellville, South Africa