基于pH响应的纳米载体制备及其黏液渗透性能研究  

Preparation and performance of pH-responsive nanocarriers for mucus penetration

作　　者：王凌玮[1] 武明豪 吴虹仪 曹琳[2] 宫晓群[3] 张雪宁[1] Wang Lingwei;Wu Minghao;Wu Hongyi;Cao Lin;Gong Xiaoqun;Zhang Xuening(Department of Medical Imaging,Second Hospital of Tianjin Medical University,Tianjin 300211,China;School of Medical Imaging,Tianjin Medical University,Tianjin 30007;School of Life Sciences,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津医科大学第二医院医学影像科,300211 [2]天津医科大学医学影像学院,300070 [3]天津大学生命科学院,300072

出　　处：《国际生物医学工程杂志》2018年第3期197-202,212,共7页International Journal of Biomedical Engineering

基　　金：天津市卫生计生委科技基金重点攻关项目;国家自然科学基金（81701826）;天津医科大学科学基金（2016KYZQ06）

摘　　要：目的 制备pH响应的渗透性纳米载体（pMPPs）,观察其在小鼠生殖道黏膜组织中的分布情况,并评估其在肿瘤细胞中的放射治疗增敏效果.方法 合成含pH敏感腙键的双亲性高分子,并使用超声乳化法制备pMPPs.同时,分别选取疏水性高分子聚乳酸-羟基乙酸共聚物（PLGA）和不含腙键的双亲性高分子PLGA-聚乙二醇,按同样方法制备黏附性纳米载体（MPs）和渗透性纳米载体（MPPs）.利用荧光显微镜观察荧光染料Cy5.5标记的3种纳米载体在小鼠生殖道黏膜组织中的分布情况.采用噻唑蓝实验检测纳米载体对人宫颈癌细胞HeLa的毒性.将含pH敏感腙键的双亲性高分子与油溶性金纳米颗粒结合形成多包裹纳米载体,再采用噻唑蓝实验评估其在HeLa细胞中的放射治疗增敏效果.结果 成功制备了pMPPs,粒径相对均一且分散性良好.荧光显微镜观察结果显示,pMPPs不仅具有良好的黏液渗透性能,还有效提高了纳米载体在小鼠生殖道黏膜组织中的进胞效率.噻唑蓝实验结果显示,当载体的质量浓度达0.80 mg/ml时,pMPPs组HeLa细胞存活率仍高于90％,且均高于MPs和MPPs组,表明pMPPs具有良好的生物安全性.在不同剂量的X射线照射下,希美纳溶液（0.80 mg/ml）组HeLa细胞存活率均高于相同质量浓度的多包裹纳米载体组（4 Gy：82.90％比61.79％;8 Gy：64.75％和42.36％）,表明相比于临床中常用的放射治疗增敏剂希美纳,多包裹纳米载体可更有效地增强肿瘤细胞对放射治疗的敏感性,从而提高放射治疗对肿瘤细胞的杀伤力.结论 本研究解决了纳米载体在黏膜组织应用中黏液渗透性能与细胞内吞设计上的冲突,为黏膜组织疾病的治疗提供了新思路.Objective To prepare pH-responsive osmotic nanocarriers （pMPPs）,observe their distribution in the genital tract mucosa in mice,and evaluate their radiosensitizing effects in tumor cells.Methods Amphiphilic polymers containing pH-sensitive hydrazone bonds were synthesized and pMPPs were prepared by ultrasonic emulsification.At the same time,the hydrophobic polymer polylactic acid-glycolic acid copolymer （PLGA） and the amphiphilic polymer PLGA-polyethylene glycol without hydrazine bond were selected,and the mucoadhesive nanoparticles（MPs） and mucus-penetrating particles （MPPs） were prepared in the same way.Fluorescence microscopy was used to observe the distribution of three kinds of nanocarriers labeled with fluorescent dye Cy5.5 in the genital tract mucosa.The toxicity of nanocarriers to human cervical cancer cell line HeLa was tested by thiazolyl blue assay.The amphiphilic polymer containing pH-sensitive hydrazone bond was combined with oil-soluble gold nanoparticles to form a multi-encapsulated nanocarrier,and its radiotherapy sensitization effect in HeLa cells was evaluated by thiazole blue assay.Results The pMPPs were successfully prepared with relatively uniform particle size and good dispersion.Fluorescence microscopy showed that pMPPs not only had good mucus permeability,but also could improve the endocytosis efficiency of the nanocarriers in reproductive tract mucosa.The results of thiazolyl blue test showed that when the concentration of the carrier reached to 0.80 mg/ml,the survival rate of HeLa cells in the pMPPs group was higher than 90% which was higher than that in the MPs and the MPPs groups,indicating that pMPPs had good biosafety.The HeLa cell survival rate of the CMNa group （0.80 mg/ml） was higher than that of the multi-package nanocarrier group under different doses of X-ray irradiation （4 Gy：82.90% vs.61.79%;8 Gy：64.75 % vs.42.36%）.This result indicated that compared with the CMNa,a commonly used clinical radiotherapy sensitizer,the multi-encapsulated nanocarriers c

关 键 词：pH响应的渗透性纳米载体 黏附性纳米载体 渗透性纳米载体 黏液 渗透性能 

分 类 号：R730.55[医药卫生—肿瘤]