Label-free electrochemical impedance genosensor based on 1-aminopyrene/graphene hybrids

Abstract

In this work, we proposed a novel simple protocol for preparing 1-aminopyrene/graphene (ApG) hybrids for fabricating label-free electrochemical impedance genosensor. Graphene, with the structure of a single-atom-thick sheet of sp(2)-bonded carbon atoms, was anchored to 1-aminopyrene (1-Ap) with the pyrenyl group viaπ-stacking interaction. The morphology, conductivity, and interaction of ApG hybrids were characterized by transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), UV-visible (UV-vis) and fluorescence spectra. The amino-substituted oligonucleotide probe was conjugated to 1-Ap by the cross-linker glutaraldehyde. The DNA hybridization reaction of oligonucleotide probe with target DNA was monitored by EIS. Under optimum conditions, the proposed biosensor exhibited high sensitivity and a low detection limit for detecting the complementary oligonucleotide. The target oligonucleotide could be quantified in a wide range of 1.0 × 10(-12) to 1.0 × 10(-8) M with good linearity (R = 0.9900) and low detection limit of 4.5 × 10(-13) M (S/N = 3).

Recent advances in electrochemical biosensing schemes using graphene and graphene-based nanocomposites

“…The covalent attachment, i.e., the formation of amide bonds between amino-terminated DNA probes and oxygen-containing groups of graphene materials using a carbodiimide, is a well-known procedure and still the predominant procedure [181]. For the covalent procedure, it might be more useful to augment the oxygen functionalities on graphene surfaces by introducing a small molecule such as perylene tetracarboxylic acid [115], poly(xanthurenic acid) [116] and 1-aminopyrene [117]. In this case, both GO and rGO with carboxylic groups serve as a better substrate and surface chemistry can be adopted to increase the number of carboxylic groups required for the covalent attachment of the DNA probe [182].…”

“…The amino group of APTES is crosslinked with the amino group of the biomolecule by glutaraldehyde activation. It is also feasible to increase the oxygen or amino functionalities on graphene surfaces by introducing carboxyl-or amino-containing molecules such as perylene tetracarboxylic acid [115], poly(xanthurenic acid) [116] and 1-aminopyrene [117]. Graphene materials decorated with gold nanoparticles (AuN- Ps) can be conjugated with thiolated biomolecules by exploiting ''well-known AuÀS'' interactions.…”

Aptamer-based biosensor for label-free detection of ethanolamine by electrochemical impedance spectroscopy

“…So electrochemical DNA sensors possess enormous potential for the task of rapid, simple and sensitive detection of target molecules [16,17] due to their convenience, high selectivity and sensitivity. And electrochemical impedance spectroscopy (EIS) has been proven to be a most powerful and sensitive tool for probing the features of surface-modified electrodes [18]. EIS biosensors possess unique advantages, such as the ability to separate the surface binding events from the solution impedance, ease of signal quantification, less damage to the biological interactions being measured, and the possibility to use non-labeled DNA [19].…”

G-quadruplex based impedimetric 2-hydroxyfluorene biosensor using hemin as a peroxidase enzyme mimic

“…Electrochemical DNA sensors are of particular interest and have been widely employed for the task of on-site detection contaminations for environmental monitoring [16][17][18][19], analysis of food, point-of-care diagnostics, fast detection of bioterrorism agents [20] as well as many other important applications due to its convenience, high selectivity and sensitivity. Especially, electrochemical impedance spectroscopy (EIS) has been proven to be a most powerful and sensitive tool for probing the features of surface-modified electrodes [21]. And EIS biosensors ([Fe(CN) 6 ] 3-/4-as redox probe couple) possess unique advantages, such as the ability to separate the surface binding events from the solution impedance, ease of signal quantification, less damage to the biological interactions being measured, and most importantly, label-free on the DNA strand [22][23][24].…”