Multi-spot, label-free detection of biomarkers in complex media by reflectionless surfaces

The measurement of the intensity of light reflected by interfaces with extremely low reflectivity in water enables the label-free, multiplex quantification of the binding between immobilized probes (e.g. antibodies) and targets in solution using extremely simple instrumental set-up. Here we show that, despite its simplicity, the method enables label-free detection in complex samples characterized by high absorbance and turbidity. Diagnostic markers of Tomato spotted wilt virus are revealed in crude plant extracts of Datura stramonium leaves with early stage infections.