Reagent-less amperometric glucose biosensor based on nanobiocomposite consisting of poly(1,10-phenanthroline-5,6-dione), poly(pyrrole-2-carboxylic acid), gold nanoparticles and glucose oxidase

In this work, a novel reagent-less amperometric glucose biosensor based on nanobiocomposite consisting of poly (1,10-phenanthroline-5,6-dione), poly(pyrrole-2-carboxylic acid) (PPCA), gold nanoparticles (AuNP) and glucose oxidase (GOx) was designed. To achieve this, the graphite rod electrode with adsorbed 1,10-phenanthroline-5,6-dione (PD) was immersed into electrochemical cell filled with a buffer solution containing pyrrole-2-carboxylic acid (PCA) and colloidal AuNP and electrochemical polymerization of PD and PCA was performed by cyclic voltammetry. During this process AuNP were encapsulated into PPCA layer. Carboxylic groups of the PPCA enabled the covalent immobilization of GOx. Optimal conditions for the biosensor working electrode preparation were elaborated and are discussed. The biosensor was characterized by wide linear range (0.2 -150.0 mM), relatively low detection limit (0.08 mM), good reproducibility (RSD 4.22 %, 2.34 % and 1.67 %, respectively for 5.0, 50.0 and 100.0 mM of glucose) and repeatability (RSD 6.93 %, 2.23 % and 1.17 %, respectively for 5.0, 50.0 and 100.0 mM of glucose), excellent stability (only 3.98 % loss of its initial activity over 14 days, when stored at 4 degrees C), high anti-interference ability to uric acid, acetaminophen and acetylsalicylic acid and demonstrated good accuracy in the analysis of pharmaceutical preparations Orsalit Drink and Rehydron Optim and human serum.