A novel homogeneous label-free aptasensor for 2,4,6-trinitrotoluene detection based on an assembly strategy of electrochemiluminescent graphene oxide with gold nanoparticles and aptamer.

We report a novel homogeneous label-free aptasensor for 2,4,6-trinitrotoluene (TNT) detection based on an assembly strategy of electrochemiluminescent graphene oxide (GO) with gold nanoparticles (AuNPs) and aptamer. In this sensing strategy, the anti-TNT aptamer was first assembled with AuNPs to form aptamer-AuNPs. Then ruthenium(II) complex functionalized GO (denoted as Ru-GO) was assembled with aptamer-AuNPs by electrostatic interaction. AuNPs could directly quench the electrochemiluminescence (ECL) emission of ruthenium(II) complex on the surface of Ru-GO due to the energy transfer from luminophore to the AuNPs. Weak ECL signal of the assembly was obtained. In the presence of target molecule TNT, the aptamer-AuNPs would aggregate partly due to the aptamer-target interaction and reduce quenching effect, leading to ECL signal restoration and strong ECL signal was obtained. TNT in a range of 0.01-100ngmL(-1) could be detected by use of the ECL intensity discrepancy with a low detection limit of 3.6pgmL(-1). The aptasensor also showed high selectivity towards TNT against 2,4-dinitrotoluene, p-nitrotoluene and nitrobenzene. The present aptasensor has been successfully applied to the detection of TNT in real water samples. Compared with previous reported sensors, this homogenous aptasensor avoided complicated labeling and purification procedure and showed magnificent sensitivity and high selectivity, which made it not only convenient but also time-saving and applicable. Furthermore, this sensing strategy also provides a promising way to develop new ECL aptasensor for other analytes by virtue of other aptamers.

[1]  D. Astruc,et al.  Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. , 2004, Chemical reviews.

[2]  Robert Langer,et al.  Self-assembled gold nanoparticle molecular probes for detecting proteolytic activity in vivo. , 2010, ACS nano.

[3]  Volker A. Erdmann,et al.  Biosensor-based on-site explosives detection using aptamers as recognition elements , 2008, Analytical and bioanalytical chemistry.

[4]  M. Zhang,et al.  Colorimetric assay for parallel detection of Cd2+, Ni2+ and Co2+ using peptide-modified gold nanoparticles. , 2012, The Analyst.

[5]  A. Xu,et al.  Plasmonic resonance energy transfer-based nanospectroscopy for sensitive and selective detection of 2,4,6-trinitrotoluene (TNT). , 2011, Chemical communications.

[6]  F. Albericio,et al.  Synthesis and in vivo evaluation of the biodistribution of a 18F-labeled conjugate gold-nanoparticle-peptide with potential biomedical application. , 2012, Bioconjugate chemistry.

[7]  D. Moore.  Instrumentation for trace detection of high explosives , 2004 .

[8]  Justyn Jaworski,et al.  Polymer-oligopeptide composite coating for selective detection of explosives in water. , 2009, Analytical chemistry.

[9]  C. M. Li,et al.  Ionic liquid–graphene composite for ultratrace explosive trinitrotoluene detection , 2010 .

[10]  G. Frens.  Controlled Nucleation for the Regulation of the Particle Size in Monodisperse Gold Suspensions , 1973 .

[11]  Kian Ping Loh,et al.  The chemistry of graphene , 2010 .

[12]  Piero Migliorato,et al.  Electrochemical aptamer-based sandwich assays for the detection of explosives. , 2012, Analytical chemistry.

[13]  Wen-Chang Shen,et al.  Synthesis of electrochemiluminescent graphene oxide functionalized with a ruthenium(II) complex and its use in the detection of tripropylamine , 2012 .

[14]  Ya-qin Wang,et al.  3-Aminopropyltriethoxysilane-functionalized manganese doped ZnS quantum dots for room-temperature phosphorescence sensing ultratrace 2,4,6-trinitrotoluene in aqueous solution. , 2011, Talanta.

[15]  Xiaogang Qu,et al.  Extraordinary physical properties of functionalized graphene. , 2012, Small.

[16]  A. Majumdar,et al.  Evolutionary screening of biomimetic coatings for selective detection of explosives. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[17]  R. Murray,et al.  Quenching of [Ru(bpy)3]2+ fluorescence by binding to Au nanoparticles , 2002 .

[18]  W. Miao,et al.  Ultrasensitive detection of TNT in soil, water, using enhanced electrogenerated chemiluminescence. , 2009, Analytica chimica acta.

[19]  Robert Wilson,et al.  Electrochemiluminescence enzyme immunoassays for TNT and pentaerythritol tetranitrate. , 2003, Analytical chemistry.

[20]  M. Pumera,et al.  Graphene-based electrochemical sensor for detection of 2,4,6-trinitrotoluene (TNT) in seawater: the comparison of single-, few-, and multilayer graphene nanoribbons and graphite microparticles , 2011, Analytical and bioanalytical chemistry.

[21]  Lianghai Hu,et al.  Aptamer in bioanalytical applications. , 2011, Analytical chemistry.

[22]  Ilaria Palchetti,et al.  Nucleic acid and peptide aptamers: fundamentals and bioanalytical aspects. , 2012, Angewandte Chemie.

[23]  Robert Wilson,et al.  Paramagnetic bead based enzyme electrochemiluminescence immunoassay for TNT , 2003 .

[24]  Samuel S. R. Dasary,et al.  Highly sensitive and selective dynamic light-scattering assay for TNT detection using p-ATP attached gold nanoparticle. , 2010, ACS applied materials & interfaces.

[25]  K. G. Thomas,et al.  Photochemistry of ruthenium trisbipyridine functionalized on gold nanoparticles. , 2006, Journal of Physical Chemistry B.

[26]  Richard G. Smith,et al.  A review of biosensors and biologically-inspired systems for explosives detection. , 2008, The Analyst.

[27]  Zhi‐Feng Zhang,et al.  Multichannel electrochemiluminescence of luminol in neutral and alkaline aqueous solutions on a gold nanoparticle self-assembled electrode. , 2004, Analytical chemistry.

[28]  Ping Yu,et al.  A simple assay for direct colorimetric visualization of trinitrotoluene at picomolar levels using gold nanoparticles. , 2008, Angewandte Chemie.

[29]  A. Govindaraj,et al.  Graphene: the new two-dimensional nanomaterial. , 2009, Angewandte Chemie.

[30]  Eun Jeong Cho,et al.  Applications of aptamers as sensors. , 2009, Annual review of analytical chemistry.

[31]  Á. Montoya,et al.  Development of a chemiluminescence-based quantitative lateral flow immunoassay for on-field detection of 2,4,6-trinitrotoluene. , 2012, Analytica chimica acta.

[32]  Evangelina Pensa,et al.  The chemistry of the sulfur-gold interface: in search of a unified model. , 2012, Accounts of chemical research.

[33]  I. Willner,et al.  Ultrasensitive surface plasmon resonance detection of trinitrotoluene by a bis-aniline-cross-linked Au nanoparticles composite. , 2009, Journal of the American Chemical Society.

[34]  Meaghan E Germain,et al.  Optical explosives detection: from color changes to fluorescence turn-on. , 2009, Chemical Society reviews.

[35]  R. Ruoff,et al.  The chemistry of graphene oxide. , 2010, Chemical Society reviews.

[36]  Xiaohong Fang,et al.  Aptamers generated from cell-SELEX for molecular medicine: a chemical biology approach. , 2010, Accounts of chemical research.

[37]  Changqing Zhu,et al.  Turn-on and near-infrared fluorescent sensing for 2,4,6-trinitrotoluene based on hybrid (gold nanorod)-(quantum dots) assembly. , 2011, Analytical chemistry.

[38]  Bin Zhang,et al.  Graphene and its derivatives: switching ON and OFF. , 2012, Chemical Society reviews.

[39]  Robert Langer,et al.  Coiled‐Coil Peptide‐Based Assembly of Gold Nanoparticles , 2004 .

[40]  Ming Zhou,et al.  Synthesis and electrochemiluminescence of bis(2,2′-bipyridine)(5-amino-1,10-phenanthroline) ruthenium(II)-functionalized gold nanoparticles , 2011 .

[41]  Antonios G. Kanaras,et al.  Programmed assembly of peptide-functionalized gold nanoparticles on DNA templates. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[42]  Ana M. Costero,et al.  Optical chemosensors and reagents to detect explosives. , 2012, Chemical Society reviews.

[43]  Chang Ming Li,et al.  Porphyrin Functionalized Graphene for Sensitive Electrochemical Detection of Ultratrace Explosives , 2011 .

[44]  Vincent M Rotello,et al.  Nano meets biology: structure and function at the nanoparticle interface. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[45]  Xiangqun Zeng,et al.  Dynamics of redox processes in ionic liquids and their interplay for discriminative electrochemical sensing. , 2012, Analytical chemistry.

[46]  Victoria L McGuffin,et al.  Luminescence-based methods for sensing and detection of explosives , 2008, Analytical and bioanalytical chemistry.

[47]  Arben Merkoçi,et al.  Graphene Oxide as an Optical Biosensing Platform , 2012, Advanced materials.

[48]  G. Eda,et al.  Graphene oxide as a chemically tunable platform for optical applications. , 2010, Nature chemistry.

[49]  Irshad Hussain,et al.  Rational and combinatorial design of peptide capping ligands for gold nanoparticles. , 2004, Journal of the American Chemical Society.

[50]  H. Cui,et al.  Electrochemiluminescence of luminol in alkaline solution at a paraffin-impregnated graphite electrode. , 2003, Analytical chemistry.