Aldehyde-Functionalized Benzenediazonium Cation for Multiprobe Immobilization on Microelectrode Array Surfaces

Abstract

We report in situ generation of aldehyde-functionalized benzenediazonium cation (ABD) and its use as a suitable linker molecule for fast and selective immobilization of biomolecules on indium-tin-oxide (ITO) electrode surfaces. We prepared ABD through a new reaction procedure, a simultaneous diazotation of the amine group and deprotection of the aldehyde group from an aniline derivative, 2-(4-aminophenyl)-1,3-dithiane, which was revealed on the ITO electrode surfaces through the electrodeposition of the reaction product and the characterization of the resulting surfaces with cyclic voltammetry, X-ray photoelectron spectroscopy, and protein immobilization. We also showed that successive electrodeposition of ABD and probe molecules on individually addressable microarray electrode surfaces can provide a useful platform for efficient detection of multianalyte. The usage of ABD has been demonstrated by the patterning of three different probe molecules on a single substrate and the simultaneous detection of two target molecules.

Reusable bio-functionalized surfaces based on electrochemical desorption of benzenediazonium-grafted organic layers

“…Very recently, we reported the synthesis of ABD from a 1,3-dithiane precursor and its use as a linker, which precluded the need for additional linkers or further activation steps prior to immobilizing biomolecules on the surface. 17 In this study, we did not use the synthetic product. Rather, we used ABD prepared by the degradation of its polymer precursor, which is commercially available.…”

Clicked Bifunctional Dendrimeric and Cyclopeptidic Addressable Redox Scaffolds for the Functionalization of Carbon Nanotubes with Redox Molecules and Enzymes

“…In the previous work on the electrografting of DTBD, the chloride salt was generated in-situ before electrochemical deposition. 33,34 Herein, we describe the synthesis of 4-( On the first scan of figure 2A, two irreversible overlapping cathodic peaks are observable at Ep red = -0.38 V and at -0.14 V. These peaks correspond to the catalyzed and uncatalyzed reduction of the diazonium group accompanied with aryl radical formation. 8,9,35 As expected, higher current densities, corresponding to a 30-fold increase, are observed on MWCNT electrodes, arising from high electroactive area of the MWCNT film (Figure 2B).…”

“…This technique has been previously employed by K. Kim and colleagues for the immobilization of labelled antibody on GC electrodes. 33,34 The obtained grafted molecule is a precursor of benzaldehyde, easily deprotected by electrochemical oxidation (Figure 1B). Following the immobilization of scaffold 1 and 2, an alkyne-ferrocene redox probe, as well as an alkyne-modified laccase and one variant, were covalently attached on the immobilized scaffolds via CuAAC.…”

“…MWCNT electrodes after transfer in a diazonium-free MeCN electrolyte. Irreversible oxidations observed at Ep ox = +0.88 V and +0.76V for GC and MWCNT electrodes, respectively, are associated with the oxidation of the 1,3 dithiane protecting group to generate benzaldehydemodified electrodes 33,34. …”

A post-functionalization toolbox for diazonium (electro)-grafted surfaces: review of the coupling methods

“…anti-rabbit IgG) via this technique was quite relevant and allowed the development of immunosensors in a selective manner. 301 Finally, we can cite the nucleophilic addition of the ''Michael'' type, which allows the coupling of amine derivatives to aromatic dihydroxy rings. This route was exploited by Cougnon et al from the grafting of a catechol phenyldiazotized derivative followed by bias-assisted coupling with model molecules bearing an amine function.…”