Nano-nose to help identify illnesses

Nanoparticles are used by U.S. researchers to 'smell' the scent of illnesses in fluids of the body. The researchers used nanoparticles of gold with different coatings to distinguish among different proteins and detect the illness, as reported by the New Scientist.

According to Vince Rotello from the University of Massachusetts the human nose has a series of receptors, which react differently to different compounds. Thus it is not a specific smell that the receptors react to, but it is a generalized response produced by the receptors, which creates the smell.

Teamed up with his colleagues from the university and with scientists from the Georgia Institute of Technology, Vince Rotello applied the same 'nose-principle' to detect proteins.

The 'nano nose' uses a system of six receptors, each one consisting of a solution with gold nano particles not larger than 2 nanometers, each one having a different coating too. Nitrogen atoms form the organic molecules which make up the coating of the nanoparticles.

Different types of proteins have different features, thus having a property to attach to various receptors, though binding with some receptors more than with others. The team's task was to identify those properties of binding for different proteins. For this purpose the team used a molecule beaming a fluorescent signal. The molecule attached to the receptor particles and then it was replaced by protein molecule when the latter bound to the receptor. This way, the more the fluorescent molecule was displaced, the more light produced. The results were subsequently analyzed by the computer.

During the experiments the scientists ran tests with 56 different proteins and proved that the signals produced by the receptors could be then used to distinguish among various proteins. The 'nano-nose' was accurate in 96 of 100 cases during these tests.

Mr. Rotello is optimistic about this accomplishment, as it could be used not just for smelling out proteins specific for a disease, but it could see the difference or the anomaly in the normal combination of proteins in the human body.

After running a series of tests with blood of sick and healthy animals, the scientists were able to identify changes in serum. They do not want to stop here and they try to make this ability statistically stable. Later on Rotello plans to make the 'nano-nose' identify different kinds of cancer cells and other diseases.

Such a nose device, sniffing out illnesses is not a novelty in the world of science and technology, as there were devices developed capable of detecting small molecules; yet the Rotello's system is the first one to detect large and complicated molecules.