Flower-Like Self-Assembly of Diphenylalanine for Electrochemical Human Growth Hormone Biosensor

Abstract

Controlling the arrangement and organization of the self-assembled material is a crucial step in the development of biosensor devices. Here, we have described a sensitive electrochemical immune biosensor based on a simple and biocompatible self-assembly method, which provides flower-like diphenylalanine peptide nanostructures (FPNSs) onto the glassy carbon electrode (GCE). Then, human growth hormone (hGH) antibody was immobilized onto the surfaces of FPNSs through the amide bonds formation between the amino groups of diphenylalanine peptide and the carboxylic groups of hGH antibody. This immune biosensor was applied for the sensitive detection of hGH. The cyclic voltammetry and electrochemical impedance spectroscopy techniques were employed for the characterization of various coating layers on the GCE. The relative charge transfer resistance of the hGH antibody/FPNSs modified GCE was found to be changed linearly with the concentration of the hGH. This electrochemical biosensor has exhibited a linear detection range of 1-100 pgmL <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> of hGH. This proposed immune-biosensor could be used as a paraclinical test for the determination of hGH.