A simple and real-time sensing of human serum albumin using antibody-modified CNT-FET

Microalbuminuria is a key indicator for the treatment of cardiovascular or cerebrovascular diseases and death. Therefore, sensitive and specific detection methods of HSA in biological fluids especially in low concentration are necessary in diagnosis and preventive medicine. Here, nanostructured electrical immunosensor is demonstrated for the rapid, sensitive and selective detection of human serum albumin (HSA), using single-walled carbon nanotube (swCNT) field-effect transistor (FETs) functionalized with monoclonal anti-human serum albumin (mAHSA) via simple coating. The selective binding of HSA with mAHSA on the surface of swCNT induces the electrostatic gating effect to the swCNT-FET. The resulting sensor exhibited high sensitivity toward HSA in real time, with good selectivity. The proposed method provides a powerful platform for a real time, sensitive and selective monitoring of HSA in biological fluids.