A glucose biosensor based on the immobilization of glucose oxidase and Au nanocomposites with polynorepinephrine

A glucose biosensor based on Au nanoparticles (AuNPs), glucose oxidase (GOD) and polynorepinephrine (PNE) was fabricated by a simple and green approach. PNE-functionalized AuNPs (AuNPs@ PNE) were synthetized by the polymerization of norepinephrine (NE) onto the surfaces of AuNPs and casted on an Au electrode. After dropping a solution containing NE and GOD on the AuNPs@ PNE-modified Au electrode and oxidizing the monomer NE by cyclic voltammetry, a PNE, GOD and AuNP-modified Au electrode (PNE/GOD/AuNPs@ PNE/Au) was obtained. The biosensor presented high sensitivity of 35.4 mA mM 1 cm 2 to glucose in the range from 0.003 mM to 3.43 mM with a response time of less than 3 s, a detection limit of 1.34 mM at a signal/noise ratio of 3, a low Michaelis-Menten constant (6.8 mM) and outstanding selectivity as well as stability. Moreover, the sensitivity and linear detection range of the asprepared biosensor were further enhanced by the addition of the redox mediator p-benzoquinone.