Electrochemical Sensing of Aptamer‐Protein Interactions Using a Magnetic Particle Assay and Single‐Use Sensor Technology

Abstract

A magnetic particle assay has been designed herein that can report the interactions of DNA aptamers with their cognate protein targets lysozyme (LYS) and human thrombin (THR). Electrochemical sensing of the biomolecular recognition between each aptamer and its target was explored by using a disposable graphite electrode, PGE, in combination with differential pulse voltammetry (DPV). The magnitudes of the oxidation signals of LYS and THR were measured at þ 780 mV and þ 680 mV, respectively, after interaction with the cognate aptamers attached to the surface of magnetic particles. The detection limits estimated for signal to noise ratios above 3.0 correspond to the concentrations of 10.77 mg/mL LYS (769 nM) and 2.00 mg/mL THR (54.5 nM). Our aptamer based approach that combines magnetic particles with a disposable graphite electrode performs well compared to other aptamer-based sensor-formats for quantitative protein detection with respect to sensitivity, selectivity, detection limit, and reproducibility.

Electrochemical Aptasensor Based on a Macrocyclic Ligand Bearing Neutral Red

“…Highlights -Novel aptasensor based on the Neutral Red (NR) and aptamer toward thrombin co-immobilized on polycarboxylated thiacalix [4]arene has been proposed for sensitive thrombin determination. -After the contact of the aptasensor with thrombin, the current of the NR reduction decayed due to steric limitation of the electron exchange in the surface layer.…”

“…

AbstractAn amperometric aptasensor has been developed by immobilization of DNA aptamer with Neutral Red (NR) on polycarboxylated thiacalix [4]arene onto the electropolymerized NR layer at a glassy carbon electrode. The NR reduction current recorded after 10 min incubation decayed with increased thrombin concentration due to limitation of the electron exchange in the surface layer.

…”

Voltammetric aptasensors for protein disease biomarkers detection: A review

“…AuPNs, AgNPs, PtNPs), silica nanoparticles (Si NPs), QDs, magnetic nanoparticles (MNPs), carbon nanotubes (CNTs), graphene (GNs) and their nanocomposites have been used for the development of electrochemical biosensors (Bai et al, 2012;Cao et al, 2014;Chen et al, 2015;Deng et al, 2013b;Hu et al, 2014;Jo et al, 2015;Li et al, 2011b;Ravalli et al, 2015;Wang et al, 2011;Zhao et al, 2011a) These nanomaterials have unique physical and chemical properties and can be used in several electrode surfaces such as GCE (Ding et al, 2010;Li et al, 2011b) and SPE (Suprun et al, 2008) in a variety of applications. For electrochemical applications, these nanomaterials allowed an easy functionalization of the electrode surfaces, namely an increase of the surface area for the aptamers attachment onto the electrode surfaces, therefore facilitating the access of the target molecule to these aptamers, and acting as electrochemical labels by increasing the signal amplification or electron-transfer mediators (Citartan et al, 2012;Erdem et al, 2009;Hernandez and Ozalp, 2012;Palchetti and Mascini, 2012;Vidotti et al, 2011;Vikesland and Wigginton, 2010;Wang et al, 2015). Taking into account these advantages, the use of nanomaterials in the development of aptasensors will lead to an increase in the sensitivity, i.e.…”

Electrochemiluminescence Aptamer Biosensor for Detection of Thrombin Based on CdS QDs/ACNTs Electrode

“…Theoretically, it is possible to obtain all kinds of aptamers to recognize virtually different target molecules with high affinity and specificity. Aptamers used for specific protein binding studies have drawn much interest recently [30][31][32][33][34][35], especially for thrombin [24,25,36,37]. However, till now, to our knowledge electrochemiluminescence aptamer biosensor for detection of thrombin based on ACNTs electrode is not reported.…”

“…Therefore, the specific recognition and quantitative detection of thrombin is extremely crucial in fundamental research as well as in clinical practice. Electrochemical [24,25] and optical techniques [26,27] were widely applied for thrombin detection. Aptamers are artificial oligonucleic acids to bind specific target molecules, which are in vitro selected by SELEX (systematic evolution of ligands by exponential enrichment) technology [28,29].…”