载血卟啉单甲醚中空金纳米球的光热光动力联合抗肿瘤研究

Study on Photothermal and Photodynamic Antitumor Activity of Hollow Gold Nanospheres Coated Hematoporphyrin Monomethyl Ether

关键词:  中空金纳米球  血卟啉单甲醚  近红外光  光热疗法  光动力疗法  肿瘤细胞

Key words:  hollow gold nanospheres  hematoporphyrin monomethyl ether  near-infrared light  photothermal therapy  photodynamic therapy  tumor cells

摘要:

目的 设计基于中空金纳米球（hollow gold nanospheres，HAuNS）的新型纳米给药系统（HMME-PEI-HAuNS），在近红外光照射下研究其同步光热光动力联合抗肿瘤作用。方法 以钴纳米粒为模板制备HAuNS，将血卟啉单甲醚（hematopor phyrin monomethylether，HMME）通过枝状聚乙烯亚胺[poly（ethylene imine），PEI]装载到HAuNS表面，形成纳米给药系统（HMME-PEI-HAuNS）；采用核磁共振氢谱、红外光谱、紫外光谱分析对HMME-PEI-HAuNS进行结构确证。建立荷瘤SKOV3小鼠模型，通过荧光活体成像仪考察其体内分布情况。将对肿瘤细胞表面EphB4受体具有特异性亲和力的靶向多肽TNYL修饰于其表面以增强该纳米体系的靶向性，用核染试剂Hoechst染色SKOV3细胞，在激光共聚焦显微镜下观察细胞内的荧光强度，用MTT比色法进行细胞毒性评价。结果 HAuNS能对HMME进行成功装载，装载率达（63.4±5.2）%。由于肿瘤的高渗透长滞留效应，HMME-PEI-HAuNS较游离HMME和HMME-PEI胶束在肿瘤部位有更多的累积量和更长的滞留时间，累计效率约为1.6%。荧光定量统计显示在TNYL多肽的介导下纳米球的靶向性更高，在808 nm激光照射下，TNYL-HMME-PEI-HAuNS发挥光热和光动力协同作用产生强大的肿瘤杀伤作用，在高浓度时，细胞存活率<10%。结论 主动靶向纳米球（TNYL-HMME-PEI-HAuNS）在808 nm近红外光照射下具有较强的光热光动力联合抗肿瘤作用。

Abstract:

OBJECTIVE To design a novel nanoparticle delivery system(HMME-PEI-HAuNS) based on hollow gold nanospheres(HAuNS), and to investigate the photothermal and photodynamic antitumor activity under the illumination of near-infrared light. METHODS HAuNS were prepared by a redox reaction using cobalt nanoparticles as a template. Hematopor phyrin monomethylether(HMME) was loaded on the surface of HAuNS via poly(ethylene imine)(PEI) as a linker to form a final nanoparticle delivery system(HMME-PEI-HAuNS). The structure of HMME-PEI-HAuNS was confirmed by NMR, IR and UV spectra. A tumor model of SKOV3 in mice was established and the biodistribution of HMME-PEI-HAuNS was investigated by fluorescence in vivo imager. Targeting peptide with specific affinity for tumor cell surface EphB4 receptors TNYL was further modified to enhance the tumor-targeting accumulation of the nanosystem. SKOV3 cells were stained with Hoechst, and the fluorescence intensity in the cells was observed using a laser confocal microscope. Cytotoxicity was evaluated by MTT colorimetry. RESULTS The HMME was successfully loaded in HAuNS with a rate of (63.4±5.2)%. Due to the enhanced permeability and retention effect of tumor, HMME-PEI-HAuNS had more accumulation and longer retention time in the tumor site than free HMME and HMME-PEI micelles, and the cumulative efficiency was about 1.6%. It was found that the targeting of nanosphere was significantly higher under the mediation of TNYL polypeptides. Under 808 nm laser irradiation, TNYL-HMME-PEI-HAuNS played a synergistic effect of photothermal and photodynamic therapy, inducing a powerful tumor cell killing, and the cell survival rate was less than 10% at high concentrations. CONCLUSION Active targeting nanosphere(TNYL-HMME-PEI-HAuNS) have strong photothermal and photodynamic antitumor effect under 808 nm NIR irradiation.