008 to 0.4 wt.%. According to the method reported by Chen et al. [35], the photothermal conversion efficiency for the this website aqueous dispersion of Cs0.33WO3 nanoparticles (2 mg/mL) under NIR irradiation (808 nm, 2.47 mW/cm2) could be determined to be 73%, close to
that of gold nanorods with an effective radius of 30 nm. Because the Cs0.33WO3 nanoparticles examined had a mean hydrodynamic diameter of 50 nm and the photothermal conversion efficiency increased with the decrease of particle size [35], this result revealed that the resulting Cs0.33WO3 nanoparticles had a photothermal conversion property comparable to gold nanorods. It was mentionable that recently, Fu et al. reported that the NIR Doramapimod in vivo irradiation by an 808-nm laser caused the partial melting of gold nanorods, leading to the decrease of photothermal conversion efficiency [36]. In this work, the photothermal
stability of Cs0.33WO3 nanoparticles under the irradiation by an 808-nm diode laser was also examined. As shown in Figure 10, after 5 cycles, the Cs0.33WO3 nanoparticles had the same photothermal conversion capability. This revealed that Cs0.33WO3 nanoparticles possessed better photothermal stability than gold nanorods under NIR irradiation. Such an excellent property makes them to become a superior candidate in NIR MK-8931 cost photothermal therapy. Figure 10 Temperature variation for aqueous dispersions of Cs 0.33 WO 3 nanoparticles with NIR irradiation time for 5 cycles. Cs0.33WO3 nanoparticles were obtained after grinding for 3 h, and their concentration in the aqueous dispersions was 0.08 wt.%. Conclusions Hexagonal Cs0.33WO3 nanoparticles with a mean hydrodynamic diameter of about 50 nm were prepared successfully in an aqueous solution of pH 8 by bead milling. They possessed excellent NIR photothermal conversion property and stability. With decreasing particle size or increasing particle concentration, the NIR photothermal conversion-induced temperature increase is enhanced. Such a nanomaterial not only could
be used in the transparent solar heat-shielding filters, but also is useful for the development of NIR-triggered photothermal conversion materials in biomedicine. Authors’ information CJC is currently a Ph.D. student of the National Cheng Kung University (Taiwan). DHC is a distinguished professor of the Chemical Engineering Department at National Cheng selleck products Kung University (Taiwan). Acknowledgments We are grateful to the National Science Council, Taiwan, for the support of this research under contract no. NSC 100-2221-E-006-164-MY2. References 1. Huang W, EI-Sayed MA: Photothermally excited coherent lattice phonon oscillations in plasmonic nanoparticles. Eur Phys J Special Topics 2008, 153:325–333.CrossRef 2. Link S, Burda C, Nikoobakht B, EI-Sayed MA: How long does it take to melt a gold nanorod? A femtosecond pump–probe absorption spectroscopic study. Chem Phys Lett 1999, 315:12–18.CrossRef 3. Link S, EI-Sayed MA: Optical properties and ultrafast dynamics of metallic nanocrystals.