Synthesis of an amine-functionalized naphthalene-containing conducting polymer as a matrix for biomolecule immobilization

Abstract

N-functionalized dithienopyrroles (DTP-NH 2) were synthesized and electropolymerized onto a graphite electrode as a novel conducting polymer matrix for biomolecule immobilization. 1 H-NMR and 13 C-NMR were utilized to investigate the characteristics of the monomer. After that, glucose oxidase (GOx) was immobilized onto the amino-functionalised matrix by means of glutaraldehyde. The surface morphologies of both DTP-NH 2 and DTP-NH 2-GOx were visualised by using SEM and fluorescence microscopy. The chronoamperometric signals of the electrochemical DTP-NH 2-GOx biosensors were measured by monitoring the O 2 consumption during an enzymatic reaction in the presence of glucose at 20.7 V. After the optimization of the pH and scan number of the polymer deposition in batch mode, the DTP-NH 2-GOx biosensor was also tested in Flow Injection Analysis (FIA) mode. The DTP-NH 2-GOx biosensors had a very good linearity between 0.05 and 1.0 mM, and between 0.1 and 2.5 mM for glucose in batch and FIA modes, respectively. Finally, it was applied for glucose analysis in real samples where commercial glucose kits were used as the reference method to verify the data obtained with the proposed biosensor.

Ferrocene-Functionalized 4-(2,5-Di(thiophen-2-yl)-1H-pyrrol-1-yl)aniline: A Novel Design in Conducting Polymer-Based Electrochemical Biosensors

“…In order to characterize the surface after co-polymer modification and immobilization of GOx, images of fluorescence microscope were recorded ( Figure 3 ) to investigate any possible changes in surface morphology after GOx immobilization. Fluorescence images can be used to show the success of the immobilization on the conducting polymer-based electrodes [ 10 , 28 – 30 ] and they are generally similar to SEM images, making them preferred as an alternative of SEM [ 9 ]. SNS-NH 2 /SNS-NH 2 -Fc/GOx modified surfaces were monitored by fluorescence microscopy after formation on the ITO glass.…”

“…Covalent bonds, especially crosslinks between the functional groups of biomolecules and polymer provides are the strongest immobilization [ 9 ]. Recently, Azak et al synthesized N-functionalized dithienopyrroles and electropolymerized onto the graphite electrode as a novel conducting polymer matrix, then glucose oxidase (GOx) was immobilized onto the amino functional surface by means of glutaraldehyde [ 10 ]. Furthermore the conducting polymer of 2-(2,5-di(thiophen-2-yl)-1 H -pyrrol-1-yl) acetic acid was electrochemically synthesized onto a graphite electrode by cyclic voltammetry and immobilization of GOx onto the polymer was performed through covalent binding using carbodiimide coupling method by Ekiz et al [ 11 ].…”

“…Several reports are available on first generation biosensors where conducting polymers were used. The principle of these biosensors was mainly based on the monitoring of oxygen consumption at −0.7 V ( vs. Ag/ACl) [ 10 – 14 , 18 ]. As an alternative to first generation enzymatic biosensors the mediated biosensors have several advantages such as less susceptibility to interfering substances and less dependency on oxygen concentration during measurements [ 19 ].…”

Poly(benzoxazine) as an Immobilization Matrix for Miniaturized ATP and Glucose Biosensors

“…In particular, electropolymerization for enzyme entrapment is attractive, as miniaturized transducers such as microelectrodes – and arrays thereof – are readily modified, which are required for limited sample volumes, for laterally resolved measurements, and for achieving fast response times. Frequently, conductive polymers and their functionalized analogues, as well as electrophoretic paints have been used as immobilization matrix. Recently, Andronescu et al .…”

Steric hindrance to the syntheses and stabilities of 1,5- and 2,6-naphthalene N-permethylated diammonium salts

“…The naphthalene compounds are of on-going interest in our group. 3 It is well known that naphthalene amines have many applications and they are useful in many fields, such as in assisted laser desorption/ionization mass spectrometry for imaging of small molecules in tissues, 4 as a part of conducting polymer as a matrix for biomolecule immobilization, 5 in the preparation of functionalized Pt nanoparticles for study of electrochemical activity and redox chemistry occurring on one surface, 6 in naphthylamine-based organic photovoltaic cells, 7 as well as for reductive electron transfer to DNA. 8 For these reasons we believe that it is important to improve known, or develop new, synthetic methods to make these compounds easily accessible.…”