By Sherwin Bryce-Pease
UNITED NATIONS, May 11 — A collaboration between the United Nations Children’s Fund (Unicef) and South Africa’s Rhodes University may revolutionise the manner in which diagnostic testing related to HIV/AIDS is done in the field.
Unicef’s Global Innovation Centre has partnered with the university’s Biotechnology Innovation Centre to develop a rapid, cost-effective testing strip which will determine a patient’s CD4 count in less than 20 minutes.
The launch of Unicef’s Innovation Centre and Innovation Fund in New York aims to bring to scale creative and cost-reducing approaches to better the lives of children. It’s about early disease detection that takes the work done in expensive laboratories into the field with the aim of obtaining the same results.
Professor Janice Limson who is Director of the Rhodes Biotechnology Innovation Centre says: “CD4 counting is obviously quite important in terms of diagnosing or indicating when anti-retroviral (ARV) therapy should be initiated.
“At the moment when people go to a clinic, they get a positive HIV result, ideally what should happen is they should get a CD4 count as well so that the healthcare worker can decide whether or not they should go on anti-retroviral therapy or not so that count and that figure is quite important.”
That’s precisely what the Colourmetric Aptamer Based Biosensor Prototype aims to do as Rhodes graduate student Jan Kruid explained: “It’s all about the colours the strip produces when blood is applied to it.
“The patient’s blood sample would be placed here (on the strip), when the CD4 in the blood interacts with the aptamer, a colour change occurs which would then generate a blue colour. So the intensity of the blue colour relates to the concentration of CD4 in the blood, a darker colour would indicate more CD4 and a lighter colour less CD4.”
The test strip is placed in a 3D printed plastic case attached to a smart phone, an app then analyzes the intensity of the blue colour to determine the CD4 count — all in under 20 minutes.
Professor Limson explains that they developed bio-recognition agents that will specifically detect CD4 in a host of different molecules in the “soup called blood” in a similar manner to glucose sensors used by diabetes sufferers to check their sugar levels.
Unicef’s innovation Centre provides technical support to proven, innovative solutions that solve challenges facing developing countries. The Centre’s Dr Sharad Sapra says: “In many parts of Africa we don’t have doctors at the service delivery point so people are working with nurses and there are no pathology labs so the drug samples have to be sent or the blood samples have to be sent far away.”
He called it a “tragedy” if patients in rural areas had to wait five to six weeks for those results. “So working with Rhodes University where they are actually working on the service point delivery of CD4 count results within 20 minutes, imagine when that is accomplished and we take it to scale in the whole of Africa as the contribution of South Africa to the rest of the developing world.”