Reversible photothermal melting of DNA in DNA-gold-nanoparticle networks.

Temperature is the most commonly applied control parameter for chemical reactions. In contexts where a very local control of reactions is important, such as in molecular self-assembly processes or lab-on-a-chip applications, it would be desirable to have a fast and precise means of manipulating the temperature on micrometer or even nanometer scales while the surrounding temperature remains unaffected. One possible tool to achieve this goal is photothermal temperature manipulation via laser irradiation of metal nanoparticles. The nanoparticles convert the absorbed light energy into heat, which is subsequently transferred to the local environment of each nanoparticle. Metal nanoparticles are very suitable absorbers since they possess extremely high absorption cross-sections associated with surface plasmons, that is, collective oscillations of conduction electrons in the metal. By choosing the particle composition, size, and geometry, the plasmonic absorption maximum can be tuned to spectral positions where no other species in the particle environment is strongly absorbing, thus enabling spectral selectivity of the heating effect. Several studies have investigated destructive processes caused by nanoparticle-assisted photothermal heating. A focus of interest lies in the investigation of nanoparticleassisted hyperthermia to be applied in cancer therapy. Csaki et al. applied metal nanoparticles to generate lesions in predefined areas of chromosomes. Nanoparticle-supported photothermia can be employed in externally triggered drug release by a selective, nanoparticle-assisted disruption of the drug-carrying capsules. Very few examples have shown reversible, that is, non-destructive, photothermally induced processes based on metal nanoparticles. Das et al. presented a photothermal volume phase transition of gold nanorod-loaded hydrogels while Jones et al. used spherical nanoparticles to generate microlenses from hydrogel phase transitions. Controlled

[1]  Michael Vollmer,et al.  Optical properties of metal clusters , 1995 .

[2]  Linyou Cao,et al.  Plasmon-assisted local temperature control to pattern individual semiconductor nanowires and carbon nanotubes. , 2007, Nano letters.

[3]  O. Gang,et al.  A simple method for kinetic control of DNA-induced nanoparticle assembly. , 2006, Journal of the American Chemical Society.

[4]  Benno Radt,et al.  Optically Addressable Nanostructured Capsules , 2004 .

[5]  W. Steen.  Absorption and Scattering of Light by Small Particles , 1999 .

[6]  George C Schatz,et al.  What controls the melting properties of DNA-linked gold nanoparticle assemblies? , 2000, Journal of the American Chemical Society.

[7]  E. Kumacheva,et al.  Microgels loaded with gold nanorods: photothermally triggered volume transitions under physiological conditions. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[8]  Zhenxin Wang,et al.  Towards multistep nanostructure synthesis: programmed enzymatic self-assembly of DNA/gold systems. , 2003, Angewandte Chemie.

[9]  Dieter Braun,et al.  The role of metal nanoparticles in remote release of encapsulated materials. , 2005, Nano letters.

[10]  L. Lyon,et al.  Photothermal patterning of microgel/gold nanoparticle composite colloidal crystals. , 2003, Journal of the American Chemical Society.

[11]  Xiaohua Huang,et al.  Cancer cell imaging and photothermal therapy in the near-infrared region by using gold nanorods. , 2006, Journal of the American Chemical Society.

[12]  C. Mirkin,et al.  Controlling anisotropic nanoparticle growth through plasmon excitation , 2003, Nature.

[13]  Dakrong Pissuwan,et al.  A golden bullet? Selective targeting of Toxoplasma gondii tachyzoites using antibody-functionalized gold nanorods. , 2007, Nano letters.

[14]  Michael J Ford,et al.  Optimization of plasmonic heating by gold nanospheres and nanoshells. , 2006, The journal of physical chemistry. B.

[15]  T. Klar,et al.  Gold nanostoves for microsecond DNA melting analysis. , 2008, Nano letters.

[16]  Karsten König,et al.  A parallel approach for subwavelength molecular surgery using gene-specific positioned metal nanoparticles as laser light antennas. , 2007, Nano letters.

[17]  Dakrong Pissuwan,et al.  Therapeutic possibilities of plasmonically heated gold nanoparticles. , 2006, Trends in biotechnology.

[18]  Xiaohua Huang,et al.  Selective laser photo-thermal therapy of epithelial carcinoma using anti-EGFR antibody conjugated gold nanoparticles. , 2006, Cancer letters.

[19]  George C. Schatz,et al.  DNA-Linked Metal Nanosphere Materials: Structural Basis for the Optical Properties , 2000 .

[20]  Hui Zhang,et al.  Immuno gold nanocages with tailored optical properties for targeted photothermal destruction of cancer cells. , 2007, Nano letters.

[21]  R. Stafford,et al.  Nanoshell-mediated near-infrared thermal therapy of tumors under magnetic resonance guidance , 2003, Proceedings of the National Academy of Sciences of the United States of America.

[22]  K. Hamad-Schifferli,et al.  Remote electronic control of DNA hybridization through inductive coupling to an attached metal nanocrystal antenna , 2002, Nature.

[23]  J. Storhoff,et al.  A DNA-based method for rationally assembling nanoparticles into macroscopic materials , 1996, Nature.

[24]  A. Johnstone.  Handbook of chemistry and physics (1st Student Edition) Edited by R. C. Weast, CRC Press Inc., Boca Raton, Florida, 1988. Price £19.95. ISBN 0‐8493‐0740‐6 , 2007 .

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

[26]  Joseph M Slocik,et al.  Peptide-assembled optically responsive nanoparticle complexes. , 2007, Nano letters.

[27]  Cheng-Dah Chen,et al.  Highly efficient, wavelength-tunable, gold nanoparticle based optothermal nanoconvertors. , 2005, The journal of physical chemistry. B.

[28]  J. Hillier,et al.  A study of the nucleation and growth processes in the synthesis of colloidal gold , 1951 .

[29]  Tarasankar Pal,et al.  Interparticle coupling effect on the surface plasmon resonance of gold nanoparticles: from theory to applications. , 2007, Chemical reviews.

[30]  Chad A Mirkin,et al.  Colorimetric screening of DNA-binding molecules with gold nanoparticle probes. , 2006, Angewandte Chemie.