Xiao Jia-Wen, Fan Shi-Xuan, Wang Feng, Sun Ling-Dong, Zheng Xiao-Yu, Yan Chun-Hua
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, China.
Nanoscale. 2014 Apr 21;6(8):4345-51. doi: 10.1039/c3nr06843a.
Nanoparticle (NP) mediated photothermal effect shows great potential as a noninvasive method for cancer therapy treatment, but the development of photothermal agents with high photothermal conversion efficiency, small size and good biocompatibility is still a big challenge. Herein, we report Pd NPs with a porous structure exhibiting enhanced near infrared (NIR) absorption as compared to Pd nanocubes with a similar size (almost two-fold enhancement with a molar extinction coefficient of 6.3 × 10(7) M(-1) cm(-1)), and the porous Pd NPs display monotonically rising absorbance from NIR to UV-Vis region. When dispersed in water and illuminated with an 808 nm laser, the porous Pd NPs give a photothermal conversion efficiency as high as 93.4%, which is comparable to the efficiency of Au nanorods we synthesized (98.6%). As the porous Pd NPs show broadband NIR absorption (650-1200 nm), this allows us to choose multiple laser wavelengths for photothermal therapy. In vitro photothermal heating of HeLa cells in the presence of porous Pd NPs leads to 100% cell death under 808 nm laser irradiation (8 W cm(-2), 4 min). For photothermal heating using 730 nm laser, 70% of HeLa cells were killed after 4 min irradiation at a relative low power density of 6 W cm(-2). These results demonstrated that the porous Pd nanostructure is an attractive photothermal agent for cancer therapy.
纳米颗粒（NP）介导的光热效应作为一种癌症治疗的非侵入性方法显示出巨大潜力，但开发具有高光热转换效率、小尺寸和良好生物相容性的光热剂仍然是一个巨大挑战。在此，我们报道了具有多孔结构的钯纳米颗粒（Pd NPs），与类似尺寸的钯纳米立方体相比，其近红外（NIR）吸收增强（摩尔消光系数为6.3×10⁷ M⁻¹ cm⁻¹，增强近两倍），并且多孔钯纳米颗粒在从近红外到紫外 - 可见区域呈现单调上升的吸光度。当分散在水中并用808 nm激光照射时，多孔钯纳米颗粒的光热转换效率高达93.4%，这与我们合成的金纳米棒的效率（98.6%）相当。由于多孔钯纳米颗粒显示出宽带近红外吸收（650 - 1200 nm），这使我们能够选择多种激光波长用于光热治疗。在多孔钯纳米颗粒存在下对HeLa细胞进行体外光热加热，在808 nm激光照射（8 W cm⁻²，4分钟）下导致100%的细胞死亡。对于使用730 nm激光的光热加热，在相对低的功率密度6 W cm⁻²下照射4分钟后，70%的HeLa细胞被杀死。这些结果表明，多孔钯纳米结构是一种有吸引力的用于癌症治疗的光热剂。
