Electrochemical Immunosensor for Sensitive Determination of TGF β1 in Urine

The first amperometric immunosensor for the quantification of TGF–β1 is described in this work. The immunosensor design involves disposable devices using carboxylic acid–functionalized magnetic microparticles supported onto screen–printed carbon electrodes and covalent immobilization of the specific antibody for TGF–β1 using Mix&Go^TM polymer. A sandwich–type immunoassay was performed using peroxidase–labeled streptavidin (Poly–HRP–Strept) polymer for signal amplification. The calibration plot allowed a range of linearity extending between 15 and 3000 pg/mL TGF–β1 (LOD 10 pg/mL). The usefulness of the immunosensor was evaluated by analyzing spiked urine at different pg/mL concentration levels.