Flourescent nanodots may help detect cancer, says IIT scientists

Scientists from IIT Mandi have found light-emitting carbon nanodots can help detect cancer cells in the body, paving the way for easier diagnoses of the deadly disease.

The research, published in the Journal of Physical Chemistry C, shows that fluorescent nanodots can reveal how water is distributed inside biological cells. The team from Indian Institute of Technology, Mandi showed that water distribution inside cancer cells differ from the normal ones.

The human body is composed of trillions of cells, with their own specialised functions. Cells have multiple constituents, of which water amounts to 80 per cent. Water molecules close to one another, are weakly attached to each other through feeble bonding forces called hydrogen bonds.

The hydrogen bonds are dynamic and change according to the interactions of water with the surroundings. The subtle changes in intracellular water, governing the cellular functionality, may initiate a series of biomacromolecular dysfunction that can lead to cancer or neurological disorders, researchers said.

The team led by Chayan K Nandi, an associate professor at IIT Mandi synthesised a fluorescent nanodot, a material that is in the scale of nanometres—about 80,000 times smaller than the width of human hair. The nanodot is made of carbon and contains both hydrophilic (water loving) and hydrophobic (water hating) parts.

RELATED

The presence of water repellent and water attracting parts within the same nanodot make them organise themselves according to the nature of the hydrogen bonding caused by the water molecules, like the formation of soap micelles around grease. 

In addition, the nanodot can emit light in the far ultraviolet wavelengths when illuminated with near ultraviolet light, and the time taken before it fluoresces depends upon the micellar arrangement of the nanodots around the hydrogen bonding network.

By introducing these nanodots into cells, the research team showed that the hydrogen bonding network is different in cancer and normal cells. The research provides the first evidence that the nuclei of cancer cells contain more free water than normal cells.

“It has been difficult to understand and experimentally analyse the extent of hydrogen bonding in intercellular water. This is the first probe to provide direct evidence of the hydrogen bonding network in an entire cell,” Nandi said in a statement.

Given the difference in water distribution in different types of cells, future research would enable the utilisation of these nanodots for detecting dysfunctional and diseased cells.