Nanoscale Energy Deposition by X-ray Absorbing Nanostructures
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- 作者：Joshua D. Carter ; Neal N. Cheng ; Yongquan Qu ; George D. Suarez ; Ting Guo
- 刊名：Journal of Physical Chemistry B
- 出版年：2007
- 出版时间：October 11, 2007
- 年：2007
- 卷：111
- 期：40
- 页码：11622 - 11625
- 全文大小：192K
- 年卷期：v.111,no.40(October 11, 2007)
- ISSN：1520-5207
文摘
Here we wish to demonstrate a unique property of nanomaterials: energy deposition with nanometer precisionfrom low-energy electrons released from these nanostructures interacting with hard X-ray radiation in aqueoussolution. Three effects combine to cause this phenomenon: (1) localized absorption of X-rays by nanostructures,(2) effective release of low-energy electrons from small nanostructures, and (3) efficient deposition of energyin water in the form of radicals and electrons. This combination creates localized X-ray absorption and localizedenergy deposition of nanometer precision. We confirmed the theoretically predicted nanoscale energy depositiondistribution by measuring hydroxyl radical-induced DNA strand breaks, and observed enhanced damage to a5600-bp DNA molecule from approximately 10 chemically conjugated small gold nanoparticles under X-rayradiation. These results provide a general guidance to applications of this new concept in many fields includingradiation chemistry, radiology, radiation oncology, biochemistry, biology, and nanotechnology.