A new nanotechnology material, D2PA, created by researchers at Princeton University can increase the sensitivity of immunoassays, such as ELISAs, by more than 3-million fold. The nanomaterial, a series of glass pillars in a layer of gold about 60 nanometers in diameter, significantly amplifies a light signal such as fluorescence.
In an immunoassay, biological markers are detected by specific antibodies, which in turn are detected by light emitting markers. The amount of light detected is directly proportional to the amount of biomarker present. However, if the amount of biomarker present is too small, the amount of light is too faint to be detected, thereby setting a limit of detection for the immunoassay. When using this new nanomaterial in an immunoassay, up to 3-million times less biomarker can be detected (0.9 nanomolars vs. 300 attomolars). This not only allows significantly less sample to be analyzed, but it may aid in earlier diagnostic of disease state biomarkers. If disease states such as cancer are detected earlier, treatment can also be started at an early stage as well.
For more information on this research see: https://www.princeton.edu/patents/news-events/news/archive/?id=7617.