Explanation:

• Institute of Nano Science and Technology (INST), an autonomous institute under the DST has found a low-cost metal-free nanomaterial for visible light microbial disinfection which can be an alternative to silver and other metal-based materials.
• Carbon Nitride Quantum Dots (g-CNQDs) are found to be a viable anti bacterial alternative to metal/non-metal semiconductors and expensive silver, thus making it cost-effective.
• These nanomaterials possess enhanced biocidal activity attributed to larger surface area of g-CNQDs having more reactive sites and optical absorption both in the ultraviolet and visible region. The g-CNQDs have the ability to generate reactive oxygen species (ROS).
• The ROS rapidly interact and damage the immediately available biological macromolecules such as lipids present on the cell membrane or envelope and proteins present on the cellular surface, towards inactivation of the microorganism.