An impedimetric immunosensor based on diamond nanowires decorated with nickel nanoparticles

Abstract

Nanostructured boron-doped diamond has been investigated as a sensitive impedimetric electrode for the detection of immunoglobulin G (IgG). The immunosensor was constructed in a three-step process: (i) reactive ion etching of flat boron-doped diamond (BDD) interfaces to synthesize BDD nanowires (BDD NWs), (ii) electrochemical deposition of nickel nanoparticles (Ni NPs) on the BDD NWs, and (iii) immobilization of biotin-tagged anti-IgG onto the Ni NPs. Electrochemical impedance spectroscopy (EIS) was used to follow the binding of IgG at different concentrations without the use of any additional label. A detection limit of 0.3 ng mL(-1) (2 nM) with a dynamic range up to 300 ng mL(-1) (2 μM) was obtained with the interface. Moreover, the study demonstrated that this immunosensor exhibits good stability over time and allows regeneration by incubation in ethylenediaminetetraacetic acid (EDTA) aqueous solution.

Functionalization of Boron-Doped Nanocrystalline Diamond with N3 Dye Molecules

“…They have for instance been used as efficient transducers for sensors. [3][4][5][6][7] B:NCD thin film electrodes decorated with metal nanoparticles have shown catalytic effects in the reduction of CO 2 and alkenes, 8 the oxidation of methanol, 9 and the degradation of environmental pollutants. 10 Recently, boron-doped diamond nanoparticles have been produced from CVD diamond films.…”

Diamond Nanostructures and Nanoparticles: Electrochemical Properties and Applications

“…The charger transfer resistance, detected from electrochemical impedance spectroscopy, was linear with IgG concentration in the range of 0.3-400 ng mL −1 . The detection limit of IgG was found to be 0.3 ng mL −1 [33]. …”

“…Furthermore, several diamond nanowires based immunosensors have been reported [33,34,38]. For instance, biotinylated anti-IgG was specifically linked to nickel particles.…”

“…4 Schematic demonstration of a trapping of cytochrome c using diamond nanotextures for an efficient electron transfer process and b the interaction of cytochrome c with the OH-terminated diamond surface [26,30] acid-terminated poly(pyrrole) [38] were applied to construct electrochemical [19], DNA biosensors [35][36][37]39], and immunosensors [32,33,38].…”

The Use of Conducting Diamond in Electrochemistry

“…In complementary work, Nebel and colleagues evaporated Ni NPs onto a BDD electrode and used the Ni as an etch mask to produce a BDD nanowire electrode terminated with Ni NPs. This 3D electrochemical platform has been utilized for the electrochemical detection of glucose [158], immobilization of histidinylated biomolecules [159], and the immunosensing of immunoglobulin G [160].…”