The biosensor is about 1 millimetre (Joan Costa/CSIC Comunicación).Scientists at the CSIC have developed a biosensor which can detect HIV-1 the first week after infection. Essays made with human serum show that the biosensor detects the p24 antigen, a protein of the HIV-1.
The biosensor detects this protein at very low concentrations, even a hundred thousand lower concentrations than the ones required by the current detection technologies. Besides, it is quick as it takes 4 hours and 45 minutes to make an analysis, therefore results can be obtained the same day. Results have been published in the PloS ONE journal.
The biosensor combines silicon micromechanical structures with gold nanoparticles, both functionalized with specific antibodies which bind to the p24 protein. If the p24 protein is present in the sample, it gets trapped between the gold nanoparticles and the silicon micromechanical structures. The combination of both structures generates mechanical and optical signals to detect the p24 protein, which amplify each other and gives as a result an outstanding sensitivity.
The technology, which has been developed and patented by the CSIC, is being applied also for the early detection of some cancers. Javier Tamayo, CSIC scientists at the Microelectronics Institute of Madrid and main investigator of this project, says that “the silicon chip is the same either for the HIV detection or for cancer detection. The only thing that changes is the chemical component which is placed to trigger the reaction depending on the target. Our main research work now is to develop more applications for this new technology”.
“The biosensor uses structures which are manufactured with current microelectronic technologies, what could enable its production at large quantities and at low cost. This together with its simplicity makes the biosensor a good option to be used in developing countries”, says Tamayo.
The technology has been licensed to the company Mecwins, a spin-off of the CSIC, created in 2008 by the CSIC scientists Javier Tamayo and Montserrat Calleja. The current research has been partially funded by the Spanish association Asociación Española contra el Cáncer.