Picomolar detection of retinol binding protein 4 for early management of type II diabetes

摘要

Type (II) diabetes is one of the major threats to mankind as it causes insulin resistance in human body and Retinol Binding Protein 4 (RBP4) is currently considered as a potential biomarker for early management of this disease. Hence a low-level detection of RBP4 is a very important task and for this purpose, a novel RBP4 biosensor has been developed using homemade plastic chip electrodes (PCEs) as a platform for self-assembled monolayer (SAM) of 4-ATP and further functionalization with glutaraldehyde. Anti RBP4 is used as biorecognition species and electrochemical impedance spectroscopy has been performed to detect different RBP4 concentrations plotted against charge transfer resistance. A wide concentration range from 100 fg/mL to 1 ng/mL has been tested and a low limit of detection (LOD) of 100 fg/mL has been achieved. This is the first report for fabrication of electrochemical biosensor of RBP4 using Ag-Ab interaction having such low LOD. The sensor is characterized by various physico-chemical techniques. Excellent reproducibility and quick measurement make this biosensor extremely useful for the biomedical industry.