A functionalized gold nanoparticles and Rhodamine 6G based fluorescent sensor for high sensitive and selective detection of mercury(II) in environmental water samples.

A gold-nanoparticles (Au NPs)-Rhodamine 6G (Rh6G) based fluorescent sensor for detecting Hg(II) in aqueous solution has been developed. Water-soluble and monodisperse gold nanoparticles (Au NPs) has been prepared facilely and further modified with thioglycolic acid (TGA). Free Rh6G dye was strongly fluorescent in bulk solution. The sensor system composing of Rh6G and Au NPs fluoresce weakly as result of fluorescence resonance energy transfer (FRET) and collision. The fluorescence of Rh6G and Au NPs based sensor was gradually recovered due to Rh6G units departed from the surface of functionalized Au NPs in the presence of Hg(II). Based on the modulation of fluorescence quenching efficiency of Rh6G-Au NPs by Hg(II) at pH 9.0 of teraborate buffer solution, a simple, rapid, reliable and specific turn-on fluorescent assay for Hg(II) was proposed. Under the optimum conditions, the fluorescence intensity of sensor is proportional to the concentration of Hg(II). The calibration graphs are linear over the range of 5.0x10(-10) to 3.55x10(-8) mol L(-1), and the corresponding limit of detection (LOD) is low as 6.0x10(-11) mol L(-1). The relative standard deviation of 10 replicate measurements is 1.5% for 2.0x10(-9) mol L(-1) Hg(II). In comparison with conventional fluorimetric methods for detection of mercury ion, the present nanosensor endowed with higher sensitivity and selectivity for Hg(II) in aqueous solution. Mercury(II) of real environmental water samples was determined by our proposed method with satisfactory results that were obtained by atomic absorption spectroscopy (AAS).

[1]  Yan Zhao,et al.  Tuning the sensitivity of a foldamer-based mercury sensor by its folding energy. , 2006, Journal of the American Chemical Society.

[2]  J. Donoghue,et al.  Baseline sediment trace metals investigation: Steinhatchee River estuary, Florida, Northeast Gulf of Mexico , 1999 .

[3]  K. G. Thomas,et al.  Selective detection of cysteine and glutathione using gold nanorods. , 2005, Journal of the American Chemical Society.

[4]  He Tian,et al.  A selective fluorescent ratiometric chemodosimeter for mercury ion. , 2005, Chemical communications.

[5]  Chih-Ching Huang,et al.  Parameters for selective colorimetric sensing of mercury(II) in aqueous solutions using mercaptopropionic acid-modified gold nanoparticles. , 2007, Chemical communications.

[6]  G. Frens.  Controlled nucleation for the regulation of the particle size in monodisperse gold solutions , 1973 .

[7]  D. Reinhoudt,et al.  Fluorescence quenching of dye molecules near gold nanoparticles: radiative and nonradiative effects. , 2002, Physical review letters.

[8]  I. Vedrina-Dragojević,et al.  Spectrofluorimetric method for the determination of the total mercury content in sediment and soil , 1997 .

[9]  Younan Xia,et al.  Gold nanostructures: engineering their plasmonic properties for biomedical applications. , 2006, Chemical Society reviews.

[10]  V. Rotello,et al.  Metal Directed Assembly of Terpyridine-Functionalized Gold Nanoparticles , 2002 .

[11]  Shu‐Yi Lin,et al.  A cooperative effect of bifunctionalized nanoparticles on recognition: sensing alkali ions by crown and carboxylate moieties in aqueous media. , 2005, Analytical chemistry.

[12]  Chang-qing Zhu,et al.  Functional InP Nanocrystals as Novel Near-infrared Fluorescent Sensors for Mercury Ions , 2005 .

[13]  B. Juskowiak.  Efficient quenching of the fluorescence of binaphthyl-based amphiphiles by mercury(II) complexes , 1996 .

[14]  John Gutknecht,et al.  Inorganic mercury (Hg2+) transport through lipid bilayer membranes , 1981, The Journal of Membrane Biology.

[15]  Laszlo Magos,et al.  The toxicology of mercury--current exposures and clinical manifestations. , 2003, The New England journal of medicine.

[16]  W. Jones,et al.  Design and Synthesis of Fluorescence “Turn-on” Chemosensors Based on Photoinduced Electron Transfer in Conjugated Polymers , 2005 .

[17]  Chih-Ching Huang,et al.  Selective gold-nanoparticle-based "turn-on" fluorescent sensors for detection of mercury(II) in aqueous solution. , 2006, Analytical chemistry.

[18]  Yi Zhang,et al.  Preparation, characterization and evaluation of water-soluble l-cysteine-capped-CdS nanoparticles as fluorescence probe for detection of Hg(II) in aqueous solution , 2006 .

[19]  Chad A Mirkin,et al.  Colorimetric detection of mercuric ion (Hg2+) in aqueous media using DNA-functionalized gold nanoparticles. , 2007, Angewandte Chemie.

[20]  H. Hashemi-Moghaddam,et al.  Flotation–Spectrophotometric Determination of Mercury in Water Samples Using Iodide and Ferroin , 2004, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry.

[21]  A. Henglein,et al.  Optical and Chemical Observations on Gold−Mercury Nanoparticles in Aqueous Solution , 2000 .

[22]  Y. Li,et al.  Gold Nanoparticle‐Based Fluorometric and Colorimetric Sensing of Copper(II) Ions , 2005 .

[23]  J. Tae,et al.  A rhodamine-based fluorescent and colorimetric chemodosimeter for the rapid detection of Hg2+ ions in aqueous media. , 2005, Journal of the American Chemical Society.

[24]  Chuan He,et al.  A general strategy to convert the MerR family proteins into highly sensitive and selective fluorescent biosensors for metal ions. , 2004, Journal of the American Chemical Society.

[25]  Matthew M. Rex,et al.  Pushing the limits of mercury sensors with gold nanorods. , 2006, Analytical chemistry.

[26]  M. Schuster,et al.  An anthracene-substituted benzoylthiourea for the selective determination of Hg(II) in micellar media , 1999 .

[27]  Igor L. Medintz,et al.  Fluorescence resonance energy transfer between quantum dot donors and dye-labeled protein acceptors. , 2003, Journal of the American Chemical Society.

[28]  Ewa Bulska,et al.  Determination of Mercury by Cold-Vapor Atomic Absorption Spectrometry with Preconcentration on a Gold-Trap , 2000 .

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

[30]  Eunkeu Oh,et al.  Inhibition assay of biomolecules based on fluorescence resonance energy transfer (FRET) between quantum dots and gold nanoparticles. , 2005, Journal of the American Chemical Society.

[31]  Jianfang Wang,et al.  Glutathione- and cysteine-induced transverse overgrowth on gold nanorods. , 2007, Journal of the American Chemical Society.

[32]  U. Bunz,et al.  Modulating the sensory response of a conjugated polymer by proteins: an agglutination assay for mercury ions in water. , 2006, Journal of the American Chemical Society.

[33]  Anthony W. Czarnik,et al.  Fluorimetric chemodosimetry. Mercury(II) and silver(I) indication in water via enhanced fluorescence signaling , 1992 .

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

[35]  Yu. A. Vil’pan,et al.  Direct atomic absorption determination of mercury in drinking water and urine using a two-step electrothermal atomizer , 2005 .

[36]  Jin-Gou Xu,et al.  Switching the recognition preference of rhodamine B spirolactam by replacing one atom: design of rhodamine B thiohydrazide for recognition of Hg(II) in aqueous solution. , 2006, Organic letters.

[37]  Sang Mi Park,et al.  Hg2+-selective OFF-ON and Cu2+-selective ON-OFF type fluoroionophore based upon cyclam. , 2006, Organic letters.

[38]  A. Ono,et al.  Highly selective oligonucleotide-based sensor for mercury(II) in aqueous solutions. , 2004, Angewandte Chemie.

[39]  Yi Lu,et al.  Stimuli-responsive disassembly of nanoparticle aggregates for light-up colorimetric sensing. , 2005, Journal of the American Chemical Society.

[40]  Paul J. Worsfold,et al.  Determination of mercury in filtered sea-water by flow injection with on-line oxidation and atomic fluorescence spectrometric detection , 1996 .

[41]  G. Szulczewski,et al.  The Effects of Mercury Adsorption on the Optical Response of Size-Selected Gold and Silver Nanoparticles , 2002 .

[42]  Catherine J. Murphy,et al.  Sensing strategy for lithium ion based on gold nanoparticles , 2002 .

[43]  Kim D Janda,et al.  A blue fluorescent antibody-cofactor sensor for mercury. , 2005, Organic letters.

[44]  X. Qian,et al.  A highly selective and sensitive fluorescent chemosensor for Hg2+ in neutral buffer aqueous solution. , 2004, Journal of the American Chemical Society.

[45]  Genhua Wu,et al.  A novel fluorescent array for mercury (II) ion in aqueous solution with functionalized cadmium selenide nanoclusters. , 2006, Analytica chimica acta.

[46]  A. Lista,et al.  Flow-injection fluorimetric determination of mercury(II) with calcein. , 1999, Talanta.

[47]  S. Gangadharan,et al.  Development of a ‘collect and punch’ cold vapour inductively coupled plasma mass spectrometric method for the direct determination of mercury at nanograms per litre levels , 1998 .

[48]  D. D. Badyukov,et al.  Determination of carbon and nitrogen in meteorites using gamma-ray activation analysis , 2005 .

[49]  Surat Hotchandani,et al.  Electrochemical modulation of fluorophore emission on a nanostructured gold film. , 2002, Angewandte Chemie.