This weekend the Director of the Institute of Nanotechnology at Northwestern University, Chad Mirkin, has revealed a new scientific advance that could be revolutionary in one of the most relevant research fields of medicine today.
It is a nanotechnology-based diagnostic system that could provide the first blood test capable of detecting Alzheimer's disease. The "biological barcode" test detects a toxic protein called ADDL.
According to Mirkin, this code could be applied in principle to any biological molecule and is much more sensitive than the conventional analysis system, the Elisa type, currently used to detect proteins in the blood. In addition to applying it to detect Alzheimer's, the team of scientists led by Mirkin hopes to take advantage of this new technological advance to detect prion diseases, LVH infection and various types of cancer.
The new medical analysis system works as follows. It makes a kind of nano-sandwich, placing the test target protein between two antibodies, each connected to a microscopic particle. One is a gold nanoparticle, to which thousands of identical DNA strands are attached. The other is a magnetic particle.
A magnet is used to separate the tiny particle-protein-particle assemblies. The DNA is then removed by the application of heat, and its content is read with the aid of a normal DNA reader.
"We believe that we have taken the first step towards an Alzheimer's analysis based on soluble markers in the blood," said scientist Prof. Mirkin.
Although recent scientific advances make it possible to recognize Alzheimer's-related neurological changes through ultrasound systems, at present the only infallible way to diagnose Alzheimer's disease is post-mortem examination of the brain.