(Published - 3 September 2019)
The overprescription of antibiotics, and failure to complete antibiotic prescriptions, have caused a rise in antibiotic resistance – a threat to human and animal health. But here’s something you may never have thought of: antibiotics in the water.
“Most antibiotics are contaminants,” explains nanochemist Siyabulela Hamnca, who recently received his PhD in Chemistry from the University of the Western Cape. “When you take antibiotics, you also excrete them into the environment – into the water, for most of us. So they stay in the environment for a while – which may lead to a rise in antibiotic resistance.”
Siyabulela’s thesis, Nanostructured polyamic acid electrocatalysts for reliable analytical reporting of sulphonamides as contaminants of emerging concern, was dedicated to understanding the mechanisms of interaction of sulphonamide antibiotics in aquatic systems.
With the guidance of his supervisor, UWC’s Prof Priscilla Baker, and collaborating with researchers at the University of Cape Town and the University of Missouri, he developed highly efficient sensor systems for the detection and quantification of a wide range of sulphonamides, employing fast response nano-polymer electrocatalysts and the complexities of dihydropteroate synthase enzymes.
“I was basically developing sensors to detect emerging contaminants – contaminants in the environment that have not yet been regulated,” Siyabulela says. “The techniques that we have, the instruments, are not designed for those kinds of contaminants.
The measurement of pharmaceuticals and their metabolites in the aquatic environment usually requires expensive state-of-the-art equipment to measure at the trace concentrations implied in health and well-being.
“Antibiotic resistance is a major threat to the wellbeing of people and the world economy. And we don’t know what other effects some of these pharmaceutical substances may have in our water systems – so why not find out?”
His work will help determine the concentrations of antibiotics in the environment, and with the help of other scientists, they can establish which levels are toxic to humans and animals, how much promotes antibiotic resistance, and also locate sources of antibiotic release into the environment.
It Takes A Village
Siyabulela Hamnca was born in the village of Rietfontein (Nxamagele), Sterkspruit, in the Eastern Cape. He was cared for by his grandmother, before he moved to Nduli, Ceres, to attend school. There he encountered that classic question: “What do you want to be when you grow up?”
“Most people talk about being police officers, or teachers – or for those with good marks, a doctor or a lawyer,” he recalls. “But for some reason I said I wanted to be a professor. My teacher was shocked – but she encouraged me to pursue it, and she checked up on me as I grew up, making sure I was still on track.”
After matric, his physics teacher helped him send applications to four universities – including UWC.
UWC is the university for me. Here I know there are people I can work with – people who are smart and capable, and who want to help other people succeed as well. At UWC, hard work can lead to a great academic future.”
His PhD journey did take him far from UWC, though – on two occasions, he spent several months at the University of Missouri (Columbia, USA), inspired by the 30-year partnership between the University of the Western Cape and University of Missouri.
“At the University of Missouri, we worked with bioengineers to develop a custom instrument to create the same nanofibres there as we do here,” he says. “Working with engineers, learning how they think and develop instruments – that was something.”
His studies took up a lot of time but he still made time for his other passion: football. Siyabulela has been part of UWC Football for a while.
“I love football. I love playing it, I love watching it, and it’s probably the thing I talk about most. Especially for township kids, who don’t have a lot of other things to occupy their time, football can provide a structure and a team that they can be part of, and that can help them develop good habits and outlooks.”
Siyabulela has been surprised to learn that he is an inspiration back home: as the first person from Nduli or Nxamagele to get his PhD.
“I didn’t even know that – I’ve never been big on talking about what I was doing, because I was so busy doing it,” Siyabulela says. “But now I can understand how important it was, and what it means to people like me, and I’m proud to be able to say a boy from a small shack in Nduli or a mud-stone house in Sterkspruit can do work that matters in any field. And if I can do it, anyone can do it – and so much more. The possibilities are endless.”