Tebello Nyokong
Spent alternate years herding sheep in Lesotho, and became one of Africa's most cited chemists
Tebello Nyokong was born in Johannesburg in 1951 and grew up in Lesotho, in the mountains. Her family could not spare her from the sheep, so she attended school in alternate years and herded in between. She has said the years outdoors were not wasted: watching animals and weather taught her to observe. She did not begin secondary school until she was well past the usual age.
She studied chemistry at the National University of Lesotho, graduating in 1977, then went to Canada for a master's degree at McMaster and a doctorate at the University of Western Ontario, finishing in 1987. She came back to southern Africa when she could have stayed in North America, and joined Rhodes University in Grahamstown in 1992, at a time when a Black woman professor of chemistry in South Africa was almost unheard of.
Her subject is phthalocyanines, a class of intensely coloured molecules related to chlorophyll. She works on using them in photodynamic therapy, in which a dye is given to a patient, gathers in a tumour and is then activated by laser light so that it destroys the cancer cells around it. The same chemistry can be turned on pollutants in water.
She has published many hundreds of papers, trained dozens of doctoral students, and won the L'Oréal-UNESCO award for women in science in 2009. She talks often about the sheep.