Experts from the University of Illinois (USA) have successfully created a biosensor chip using carbon nanotubes. When introduced into living cells, it helps detect harmful pollutants.
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DNA wrapped around carbon nanotube (Photo: VNN) |
According to Professor Michael Strano from the University of Illinois, this is the first sensor chip made from carbon nanotubes that can detect pollutants at sub-cellular levels.
This success paves the way for new types of optical sensor chips that exploit the unique properties of nanoparticles within living structures.
To create the sensor, researchers wrapped a double-stranded DNA segment around the surface of the carbon nanotube. The wall of the nanotube consists of a single layer. Consequently, the DNA adopts a specific shape.
When this DNA is exposed to ions of certain atoms, such as calcium, mercury, and sodium, its shape changes.
The change in shape reduces the surface area covered by the DNA, causing disruptions in the electronic structure. As a result, the natural near-infrared fluorescence capability of the nanotube is shifted to a lower energy level.
This change in energy level indicates the amount of ions adhering to the DNA. Removing these ions restores the energy level of the DNA, allowing the sensor chip to be reused.
The research team demonstrated that the sensor can detect low levels of mercury ions in the blood, tissues, and cells of mammals.
Minh Sơn (According to Science Today)
