Graphene quantum dots drawn from anthracite and bituminous coal may be the basis for an effective antioxidant for people who suffer traumatic brain injuries, strokes or heart attacks. Quantum dots are semiconducting materials small enough to exhibit quantum mechanical properties that only appear at the nanoscale.
A team of scientists from three different universities in Texas discovered that biocompatible dots, when modified with a common polymer, are effective mimics of the body’s own trauma fighting ability oxidative stress.
However, following a traumatic injury, the body’s natural antioxidants can be overwhelmed by the rapid production of reactive oxygen species (ROS) that race to heal an injury. ROS are chemically reactive chemical species containing oxygen. Examples of ROS include peroxides, superoxide, hydroxyl radical, singlet oxygen, and alpha-oxygen.
The team of scientists has been working for years to see if a quick injection of reactive nanomaterials can limit the collateral damage these free radicals can cause to healthy cells.
In a new study, the researchers evaluated the dots’ electrochemical, chemical and biological activity. A lab at Rice University in Texas chemically extracted quantum dots from inexpensive bituminous and anthracite coal, modified them with the polymer and tested their abilities on live cells from rodents.
The results showed that quantum dot doses in various concentrations were highly effective at protecting cells from oxidation, even if the doses were delayed by 15 minutes after researcher’s added damaging hydrogen peroxide to the cell culture dishes.
The disclike, 3-5-nanometer bituminous quantum dots are smaller than the 10-20-nanometer anthracite dots. The researchers found the level of protection was dose-dependent for both types of particles, but that the larger anthracite-derived dots protected more cells at lower concentrations.
“Although they both work in cells, in vivo, the smaller ones are more effective.” Said project scientist James Tour, Professor of Chemistry at Rice University. “The larger ones likely have trouble accessing the brain as well.”Go back to previous page