INDIA
The focus of research on the potential health benefits of tea has increasingly moved from the leaf in the cup to extracted biochemical compounds in the test tube. One of these is the “magic molecule” EGCG (epigallocatechin-3-gallate) that has made green tea of growing evidence of powerful potential for cancer treatment.
Add to this quantum dots. These are tiny nanoparticles that recent studies have found kill cancer cells in vitro – a term that is Latin for “within the glass”: in the lab test tube or petri dish, and on mice, using extracted cancer cells. It contrasts within vivo – within the living human body. Here, biochemical, metabolic side effect interactions and many other factors may dissipate or alter the encouraging lab results. That said, nanoparticles extracted from tea open up new horizons of application, including transforming the dangerous processes by which the particles are made and used in a wide range of industrial applications and foods.
Nanoparticles have a diameter of 1-100 nanometers. Quantum dot is the label for those around 10 nm in size. The width of a human hair is 40,000 nanometers. They have special physical, chemical, and optical properties that are a product of their small size and large proportional surface area. The particles are in wide use in coloring TV screens, solar panel radiation absorption, medical imaging, materials reinforcement, drug delivery within the body, removal of contamination in groundwater, and elimination of bacteria in foods and textiles. The famous adage of the science fiction writer Arthur C. Clarke, seems application to the world of nano: “Any sufficiently advanced technology is indistinguishable from magic.” This is all magical.
But it is also black magic. Producing nanoparticles is complex, hazardous, and difficult to control. Many of the base materials are metals and ceramics with high potential for toxicity. They easily became environmental hazards due to the ease with which they bind to and catalyze other molecules and penetrate cell membranes. Many effects are unknown: CeO2 (cesium dioxide) particles in fuel additives are under investigation by the EPA safety research unit for environmental, ecological, and health impacts, for instance.
This all may seem to have little to do with tea but several lab studies are making tea more than just relevant. The lab evidence is that certain quantum dots can be safely and inexpensively made using green tea extract as a stabilizing medium. This in itself greatly reduces risks of toxicity. Between 2010 and 2019, it has been successfully used to make silver and gold nanoparticles, by incubating. For instance, silver nitrate.
A collaborative research project between teams at the UK University of Swansea and India’s KSR Institute of Technology and Bharathiar University successfully used tea extract to incubate a cadmium sulphide and sodium sulphide mix to produce quantum dots as an alternative to chemical methods. (2018 reports.) Instead of removing the tea and disposing of it as waste, the researchers left it as part of the quantum dot composition. They then tested the dots for antibacterial properties, bioimaging application potential.
And for their impact on the growth of cancer cells. The results were a surprise. The dots are able to penetrate cancer cells through tiny nanopores. They can then be nanocarriers of cancer cell killers. In this instance, properties of the green tea reached the cells and destroyed as many as 80%. The exact causes are unclear and follow on studies will be needed before quantum dots derived from green tea are shown to be a practical and effective part of cancer prevention and cure. It’s magic.