|
Nyokong in the lab with some of her students |
Professor Tebello Nyokong, known around the world for her pioneering research into photodynamic therapy for cancer treatment with a series of prestigious accolades to her name, including winning the Africa-Arab State 2009 L'Oreal-Unesco Award for Women in Science, is a long-term grantholder in the CSIR National Laser Centre's rental pool programme.
In a recent interview, Nyokong talked about her gratitude to the CSIR saying, "My lifeline happened when I received a call from a gentleman a few years ago saying the CSIR was visiting Rhodes University and wanted to meet to discuss its laser rental programme. You see, I had been trying to do laser research for years but the system costs R2 million and nobody was prepared to sponsor me."
Nyokong explains, "As a young researcher you need money; but to get money you need experience; and you need experience to get money, so it's a cycle that doesn't end! Thus, this was the turning point in my research."
This defining moment in Nyokong's research endeavours also solidified her relationship with the CSIR. "I love light and what a better way to do your research than with the most beautiful form of light, lasers! When I got the first test of my cancer drugs in cells and they showed brilliant activity towards cancer, I knew I was on the right track." Nyokong is recognised as one of the top three publishing scientists in South Africa; has won the 2004 Shoprite/Checkers Woman of the Year in Science and Technology award and if that is not a mouthful already, she was also awarded the Bronze Order of Mapungubwe in 2005 by former president Thabo Mbeki.
Phthalocyanine molecules?
Passionate about her work, Nyokong says, "Cancer remains a major burden to human health. The treatment of tumours in cancer therapy is an important part of the recovery process from the effects of cancer. My work involves the synthesis of novel phthalocyanine molecules (Pc) for photodynamic therapy (PDT) for the treatment of cancerous tumours." Pc molecules have been under investigation for several years as potential photosensitisers for the destruction of cancers, with promising results.
However, Nyokong says, "There is still a considerable amount of research needed in tailoring these molecules to the photochemical and biological requirements of a successful photosensitiser."
Pc molecules are basically blue or green dyes. "They are used for anything that come in these colours; be it pens, paint, clothes, you name it. Half a million tons of these molecules are produced worldwide every year and sold for dyes. The beauty of these molecules is that they are roughly the same structure as chlorophyll in plants and heme found in human bodies. We felt that because of this these molecules would be compatible with the body and as such suitable for use in medicine." Each hemoglobin molecule is made up of four heme groups surrounding a globin group. Heme, which accounts for 4% of the weight of the molecule, is composed of a ringlike organic compound known as a porphyrin to which an iron atom is attached.
Taking it a step further
"What we do is modify the Pc molecules so that they become soluble in water. This is the beauty of chemistry - we are designers! It is a lengthy process and takes a lot of skill." Nyokong explains, "Various differently substituted Pc molecules have been used in PDT of cancer and some requirements are apparent, such as the need for a diamagnetic central metal and peripheral substituent that produce an overall water-soluble and fat-soluble molecule. Thus, metal Pc molecules are being developed by our group." Nyokong's group is using zinc (also found in the body) in these studies, while industry uses copper, the cheaper option.
"If this form of therapy is brought to South Africa, it could have far-reaching benefits to our people, even in the context of HIV/Aids."
No ordinary scientist
Nyokong continues to do outstanding work in training chemists, particularly women, in the sophisticated skills needed to keep South Africa at the cutting edge of scientific development. "I have extensive collaborations with international researchers from Japan, China, UK, France, Belgium, Switzerland, Germany and Romania. I travel to these countries regularly and it is exciting. I get new ideas from my visits and also get a lot of visitors from all over the world that enrich my research." Nyokong is adamant that Africa has a lot to offer. "I object to a situation where Africans are always beggars. When I collaborate with someone it must be mutual. It must not be a favour - I don't do well with favours - we are good at what we do! Hence, it is about mutual exchange and respect."
Enquiries: CSIR Communication
|
