Band-selective coupling-induced enhancement of two-photon photoluminescence in gold nanocubes and its application as turn-on fluorescent probes for cysteine and glutathione.

We have demonstrated that cysteine and glutathione induced edge-to-edge coupling of gold nanocubes (Au NCs) caused a band-selective enhancement of two-photon photoluminescence (TPPL). The photoluminescence intensity of the X-band of Au NCs was found to be enhanced up to 60-fold and 46-fold upon addition of cysteine and glutathione, respectively, while the intensity of L-band remained almost unchanged. This band-selective enhancement behavior is totally different from the previously observed aggregation enhanced TPPL of spherical metal nanoparticles (NPs). The band-selective enhancement was ascribed to preferential enhancement of the X-band emission through resonant coupling with longitudinal surface plasmon resonance (SPR) band of the Au NCs assembly. This phenomenon was utilized to develop a new two-photon fluorescence turn-on sensing platform for detection of cysteine and glutathione. This method displayed high sensitivity and excellent selectivity over the other 19 amino acids. Together with the advantage of deep tissue penetration and localized excitation of two-photon near-infrared excitation, this strategy has promising applications in in vivo biosensing and imaging.

[1]  P. Mulvaney,et al.  Surface plasmon resonances in strongly coupled gold nanosphere chains from monomer to hexamer. , 2011, Nano letters.

[2]  Anjan Kr Dasgupta,et al.  Cell selective response to gold nanoparticles. , 2007, Nanomedicine : nanotechnology, biology, and medicine.

[3]  Hiromi Okamoto,et al.  Plasmon mode imaging of single gold nanorods. , 2004, Journal of the American Chemical Society.

[4]  Yu Qin,et al.  Functional nanoprobes for ultrasensitive detection of biomolecules. , 2010, Chemical Society reviews.

[5]  Xingyu Jiang,et al.  Gold nanoparticles for the colorimetric and fluorescent detection of ions and small organic molecules. , 2011, Nanoscale.

[6]  Y V Tcherkas,et al.  Simultaneous determination of several amino acids, including homocysteine, cysteine and glutamic acid, in human plasma by isocratic reversed-phase high-performance liquid chromatography with fluorimetric detection. , 2001, Journal of chromatography. A.

[7]  Philip S Low,et al.  In vitro and in vivo two-photon luminescence imaging of single gold nanorods. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[8]  G. Wiederrecht,et al.  Surface plasmon characteristics of tunable photoluminescence in single gold nanorods. , 2005, Physical review letters.

[9]  G S Kino,et al.  Improving the mismatch between light and nanoscale objects with gold bowtie nanoantennas. , 2005, Physical review letters.

[10]  Tao Yi,et al.  A highly selective fluorescence turn-on sensor for cysteine/homocysteine and its application in bioimaging. , 2007, Journal of the American Chemical Society.

[11]  Jianfang Wang,et al.  Nanonecklaces assembled from gold rods, spheres, and bipyramids. , 2007, Chemical communications.

[12]  Thomas A. Klar,et al.  Plasmon emission in photoexcited gold nanoparticles , 2004 .

[13]  Z. A. Wood,et al.  Structure, mechanism and regulation of peroxiredoxins. , 2003, Trends in biochemical sciences.

[14]  Jianfang Wang,et al.  Plasmon-induced modulation of the emission spectra of the fluorescent molecules near gold nanorods. , 2011, Nanoscale.

[15]  Hiromi Okamoto,et al.  Near-field two-photon-induced photoluminescence from single gold nanorods and imaging of plasmon modes. , 2005, The journal of physical chemistry. B.

[16]  Rongchao Jin,et al.  Correlating second harmonic optical responses of single Ag nanoparticles with morphology. , 2005, Journal of the American Chemical Society.

[17]  Aharon Gedanken,et al.  The Surface Chemistry of Au Colloids and Their Interactions with Functional Amino Acids , 2004 .

[18]  Logan K. Ausman,et al.  Methods for describing the electromagnetic properties of silver and gold nanoparticles. , 2008, Accounts of chemical research.

[19]  M. El-Sayed,et al.  The `lightning' gold nanorods: fluorescence enhancement of over a million compared to the gold metal , 2000 .

[20]  Jianfang Wang,et al.  Curvature-directed assembly of gold nanocubes, nanobranches, and nanospheres. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[21]  Qing-Hua Xu,et al.  Size-dependent two-photon excitation photoluminescence enhancement in coupled noble-metal nanoparticles. , 2012, ACS applied materials & interfaces.

[22]  Weihai Ni,et al.  pH-Controlled reversible assembly and disassembly of gold nanorods. , 2008, Small.

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

[24]  S. Shahrokhian,et al.  Lead phthalocyanine as a selective carrier for preparation of a cysteine-selective electrode. , 2001, Analytical chemistry.

[25]  T. Klar,et al.  Shaping emission spectra of fluorescent molecules with single plasmonic nanoresonators. , 2008, Physical review letters.

[26]  Coupled nanoantenna plasmon resonance spectra from two-photon laser excitation. , 2010, Nano letters.

[27]  Sarit S. Agasti,et al.  Gold nanoparticles in chemical and biological sensing. , 2012, Chemical reviews.

[28]  C. Noguez.  Surface Plasmons on Metal Nanoparticles: The Influence of Shape and Physical Environment , 2007 .

[29]  Emil Prodan,et al.  Plasmon Hybridization in Nanoparticle Dimers , 2004 .

[30]  Younan Xia,et al.  Isolating and probing the hot spot formed between two silver nanocubes. , 2009, Angewandte Chemie.

[31]  Jianfang Wang,et al.  Experimental evidence of plasmophores: plasmon-directed polarized emission from gold nanorod-fluorophore hybrid nanostructures. , 2011, Nano letters.

[32]  Steven R. Emory,et al.  Probing Single Molecules and Single Nanoparticles by Surface-Enhanced Raman Scattering , 1997, Science.

[33]  P. Ray.  Size and shape dependent second order nonlinear optical properties of nanomaterials and their application in biological and chemical sensing. , 2010, Chemical reviews.

[34]  Xin Wang,et al.  High-photoluminescence-yield gold nanocubes: for cell imaging and photothermal therapy. , 2010, ACS nano.

[35]  Petru Ghenuche,et al.  Spectroscopic mode mapping of resonant plasmon nanoantennas. , 2008, Physical review letters.

[36]  Hiroyuki Yokoyama,et al.  Observation of spontaneous emission lifetime change of dye‐containing Langmuir–Blodgett films in optical microcavities , 1991 .

[37]  Shen,et al.  Photoinduced luminescence from the noble metals and its enhancement on roughened surfaces. , 1986, Physical review. B, Condensed matter.

[38]  H. Ehrenreich,et al.  Optical Properties of Ag and Cu , 1962 .

[39]  M. El-Sayed,et al.  Spectral Properties and Relaxation Dynamics of Surface Plasmon Electronic Oscillations in Gold and Silver Nanodots and Nanorods , 1999 .

[40]  Zongfu Yu,et al.  Large single-molecule fluorescence enhancements produced by a bowtie nanoantenna , 2009 .

[41]  Freya Q. Schafer,et al.  Redox environment of the cell as viewed through the redox state of the glutathione disulfide/glutathione couple. , 2001, Free radical biology & medicine.

[42]  O. Martin,et al.  Resonant Optical Antennas , 2005, Science.

[43]  Qing-Hua Xu,et al.  Enhanced two-photon emission in coupled metal nanoparticles induced by conjugated polymers. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[44]  Alaaldin M. Alkilany,et al.  Gold nanoparticles in biology: beyond toxicity to cellular imaging. , 2008, Accounts of chemical research.

[45]  M. Broyer,et al.  Surface Plasmon Resonance of Single Gold Nanodimers near the Conductive Contact Limit , 2009 .

[46]  Marco Finazzi,et al.  Dependence of the two-photon photoluminescence yield of gold nanostructures on the laser pulse duration , 2009 .

[47]  E. Coronado,et al.  The Optical Properties of Metal Nanoparticles: The Influence of Size, Shape, and Dielectric Environment , 2003 .

[48]  Lisa B. Israel,et al.  Colorimetric detection of thiol-containing amino acids using gold nanoparticles. , 2002, The Analyst.

[49]  Qing-Hua Xu,et al.  Two-photon ratiometric sensing of Hg2+ by using cysteine functionalized Ag nanoparticles. , 2011, Nanoscale.

[50]  R. Rosei,et al.  Splitting of the interband absorption edge in Au , 1975 .

[51]  Lukas Novotny,et al.  Continuum generation from single gold nanostructures through near-field mediated intraband transitions , 2003 .

[52]  Qinghua Xu,et al.  Water-soluble conjugated polymer-induced self-assembly of gold nanoparticles and its application to SERS. , 2008, Langmuir : the ACS journal of surfaces and colloids.