Green tea quantum dots unexpectedly destroy lung cancer cells

(Credit: NuCastiel via Flickr)

Quantum dots are nanoparticles used in everything from computers and solar cells to tumour imaging. The process used to make them can be expensive and sometimes results in toxic side effects.

In the search for a plant-based alternative, the Swansea team mixed green tea leaf extract with cadmium sulphate (CdSO₄) and sodium sulphide (Na₂S). The solution was allowed to incubate, causing quantum dots to form. Working alongside two Indian universities, the UK-based researchers were initially able to back up previous work conducted on quantum dots made using tea leaves.

“Our research confirmed previous evidence that tea leaf extract can be a non-toxic alternative to making quantum dots using chemicals,” said lead researcher Dr Sudhagar Pitchaimuthu.

“The CdS quantum dots derived from tea leaf extract showed exceptional fluorescence emission in cancer cell bioimaging compared to conventional CdS nanoparticles. They also have other possible applications, for example in anti-microbial paint used in operating theatres, or in sun creams.”