Theranostics 2014; 4(9):904-918. doi:10.7150/thno.9448

Research Paper

Theranostic Self-Assembly Structure of Gold Nanoparticles for NIR Photothermal Therapy and X-Ray Computed Tomography Imaging

Heng Deng1,2, Yanqi Zhong1,2, Meihong Du3, Qinjun Liu3, Zhanming Fan4✉, Fengying Dai1,✉, Xin Zhang1,✉

1. National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
2. University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing, 100049, China.
3. Beijing Center for Physical and Chemical Analysis, Beijing, 100089, China.
4. Department of Radioloy, Beijing Anzhen Hospital, Capital University, No. 2 Anzhen Road, Chaoyang District, Beijing, China.

Abstract

The controllable self-assembly of amphiphilic mixed polymers grafted gold nanoparitcles (AuNPs) leads to strong interparticle plasmonic coupling, which can be tuned to the near-infrared (NIR) region for enhanced photothermal therapy (PTT). In this study, an improved thiolation method was adopted for ATRP and ROP polymer to obtain amphiphilic brushes of PMEO2MA-SH and PCL-SH. By anchoring PCL-SH and PMEO2MA-SH onto the 14 nm AuNPs, a smart hybrid building block for self-assembly was obtained. Increasing the PCL/PMEO2MA chain ratio from 0.8:1, 2:1 and 3:1 to 7:1, the structure of gold assemblies (GAs) was observed to transfer from vesicle to large compound micelle (LCM). Contributed to the special dense packed structure of gold nanoparticles in LCM, the absorption spectrometry of gold nanoparticles drastically red-shifted from 520 nm to 830 nm, which endowed the GAs remarkable NIR photothermal conversion ability. In addition, gold has high X-ray absorption coefficient which qualifies gold nanomaterial a potential CT contrast agent Herein, we obtain a novel gold assembly structure which can be utilized as potential photothermal therapeutic and CT contrast agents. In vitro and In vivo studies testified the excellent treatment efficacy of optimum GAs as a PTT and CT contrast agent. In vitro degradation test, MTT assay and histology study indicated that GAs was a safe, low toxic reagent with good biodegradability. Therefore, the optimum GAs with strong NIR absorption and high X-ray absorption coefficient could be used as a theranostic agent and the formation of novel gold large compound micelle might offers a new theory foundation for engineering design and synthesis of polymer grafted AuNPs for biomedical applications.

Keywords: Photothermal therapy, polymer grafted gold nanoparticles, theranostics, near-infrared absorption, large compound micelles

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How to cite this article:
Deng H, Zhong Y, Du M, Liu Q, Fan Z, Dai F, Zhang X. Theranostic Self-Assembly Structure of Gold Nanoparticles for NIR Photothermal Therapy and X-Ray Computed Tomography Imaging. Theranostics 2014; 4(9):904-918. doi:10.7150/thno.9448. Available from http://www.thno.org/v04p0904.htm