SuFIDA Assay
In medical diagnostics and biotechnological applications, immunoassays, such as the so-called ELISA method (enzyme-linked immunosorbance assay), have been state-of-the-art for more than four decades. However, since these are always ensemble measurements with only one measured value per sample, ELISA methods are limited in several respects, especially with regard to the dynamic measuring range and sensitivity. This conventional analog method can be replaced by digital SuFIDA technology. Due to its single molecule sensitivity, SuFIDA technology has a digital readout that is linearly dependent on analyte concentration over at least four orders of magnitude and is already superior to any ELISA.
SuFIDA (surfaced-based fluorescence immuno digital assay) is the combination of the reliable biochemical part of a sandwich ELISA and the readout using an imaging technique.
The SuFIDA process. A capture antibody immobilizes the analyte from the sample onto a glass surface. Components not bound to the surface are removed by washing. A fluorescence-labeled antibody is used as the detection probe, which recognizes an epitope on the target molecule that is not occupied by the capture antibody. Using highly sensitive fluorescence microscopy, all individual fluorescence-labeled probes on the surface can now be detected and virtually counted individually.
Properties of SuFIDA:
• Digital process
• million readings per sample
• multiplex measurement possible
• Linear measuring range over 4-5 orders of magnitude
• Femtomolar sensitivity
The core property of SuFIDA is the highly specific single molecule sensitivity. This is particularly important when, for example, body liquids like urine, saliva or blood contain only low abundant analytes. The SuFIDA Innovation Lab focuses on the development of biomarkers and analytes with high medical relevance and thus commercial potential.
The innovation has pipetting robots as well as automated "high-end" microscopes from Leica, Zeiss and Cytiva.