State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
Small. 2014 Aug 13;10(15):3139-44. doi: 10.1002/smll.201303631. Epub 2014 Apr 14.
Efficient renal clearance is of fundamentally important property of nanoparticles for their in vivo biomedical applications. In this work, we report the successful synthesis of ultra-small Pd nanosheets (SPNS) with an average diameter of 4.4 nm and their application in photothermal cancer therapy using a near infrared laser. The ultra-small Pd nanosheets have strong optical absorption in the NIR region and high photothermal conversion efficiency (52.0%) at 808 nm. After being surface-functionalized with reduced glutathione (GSH), the SPNS-GSH was administered to mice to investigate the biodistribution, photothermal efficacy and tumor ablation in vivo. The in vivo photothermal therapy studies clearly demonstrate that surface modification with GSH allows the nanosheets to exhibit prolonged blood circulation and thus high accumulation in tumors. Upon 808 nm NIR irradiation, the tumors can be completely ablated. More importantly, with the size below the renal filtration limit (<10 nm), the GSHylated Pd nanosheets can be nicely cleared from body through the renal excretion route and into urine. Together with the high efficacy of NIR photothermal therapy, the unique renal clearance properties make the ultra-small Pd nanosheets promising for practical use in photothermal cancer therapy.
高效的肾脏清除率是纳米粒子用于体内生物医学应用的基本重要性质。在这项工作中，我们报告了成功合成了平均直径为 4.4nm 的超小钯纳米片（SPNS），并将其应用于近红外激光的光热癌症治疗。超小钯纳米片在近红外区域具有很强的光吸收，在 808nm 处具有高光热转换效率（52.0%）。经过还原型谷胱甘肽（GSH）表面功能化后，将 SPNS-GSH 施用于小鼠，以研究体内的生物分布、光热疗效和肿瘤消融。体内光热治疗研究清楚地表明，用 GSH 进行表面修饰可以使纳米片表现出延长的血液循环，从而在肿瘤中高度积累。在 808nm 近红外照射下，肿瘤可以完全消融。更重要的是，由于尺寸小于肾脏滤过极限（<10nm），GSH 化钯纳米片可以通过肾脏排泄途径很好地从体内清除，并进入尿液。结合近红外光热疗法的高效性，独特的肾脏清除特性使超小钯纳米片在光热癌症治疗中有很好的实际应用前景。
