Sensor chip made from carbon nanotubes

Experts from the University of Illinois (USA) have used carbon nanotubes to successfully manufacture biological sensor chips. When introduced into living cells, it helps detect toxic pollutants.

DNA is wrapped around carbon nanotubes (Photo: VNN)

According to Michael Strano of the University of Illinois, this is the first sensor chip, made of carbon nanotubes, that can detect contaminants below the cellular level.

This success will pave the way for new types of optical sensor chips, taking advantage of the unique properties of nanoparticles in living structures.

To make the sensor, the researchers wrapped a piece of double-stranded DNA around the surface of the carbon nanotube. The pipe wall has only one layer. Therefore, DNA will have a certain shape.

When this DNA is exposed to the ions of certain atoms , such as calcium, mercury and sodium, its shape changes.

The changing shape makes the surface area covered with DNA decrease, causing the electronic structure to be disturbed. Therefore, the sulfur ability around the natural near-infrared of nanotubes is transferred to lower energy levels.

The change in the energy level indicates the amount of ion clinging to the DNA. Removing these ions will restore the energy level for DNA. Thus, sensor chips can be reused.

The team has shown that sensors have the ability to detect low levels of mercury ions in the blood, tissue and cells of mammals.

Minh Son (According to Science Today)