In the functionalized approach, the very low LODs of about 0.46 ng/mL and 0.14 ng/ml estimated for Stx1a and Stx2a, respectively, also highlight the ability of the developed system to carry out analysis and detection of concentrations of the investigated cytotoxins that are lower than those found in patients’ sera (2–6 ng/ml by ELISA) before the development of HUS [97]. This evidence concerns the gene STX2 and hemolytic-uremic syndrome.