Synergistic regulation of longitudinal and transverse relaxivity of extremely small iron oxide nanoparticles (ESIONPs) using pH-responsive nanoassemblies
Synergistic regulation of longitudinal and transverse relaxivity of extremely small iron oxide nanoparticles (ESIONPs) using pH-responsive nanoassemblies
复制标题
使用 pH 响应纳米组件协同调节极小氧化铁纳米颗粒 (ESIONP) 的纵向和横向弛豫率
DOI：
10.1039/d0nr04201c
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发表时间：
2020
期刊：
影响因子：
6.7
通讯作者：
Pei Renjun
中科院分区：
文献类型：
--
作者：
Cao Yi;He Yilin;Mao Zheng;Kuang Ye;Liu Min;Zhang Ye;Pei Renjun
超小氧化铁纳米粒子（Extremely small iron oxide nanoparticles，ESIONP）作为一种特殊的T1磁共振成像（magnetic resonance imaging，MRI）造影剂，由于其磁性无序的外壳相对于其磁性核心占优势，可提供T1对比增强，具有很强的潜力用于构建刺激响应性造影剂（stimuli-responsive contrast agents，CA），实现高特异性和灵敏度的肿瘤精确诊断。基于ESIONP的CA的刺激响应功能可以通过协同调节ESIONP的纵向和横向弛豫率（r1和r2）来直接赋予。然而，对ESIONP的r1和r2协同调控机制的系统研究还相当缺乏。本文基于弛豫理论，设计并构建了三种具有pH响应性的ESIONP纳米组装体，探讨了对r1和r2的各种协同调控的可能性。当三种ESIONP基纳米组装体在弱酸环境下转化为解离态时，ESIONP胶束可实现单一r2随稳定r1沿着下降的协同调节，而金纳米粒子-ESIONP（AuNPs-ESIONP）囊泡可以提供协同调节，包括单一的r1增加沿着稳定的r2，ESIONP囊泡可能提供协同调节，涉及r2降低和r1增加。此外，对r1和r2的协同调控是构建具有刺激响应功能的ESIONP类CA的有效策略。这些r1和r2的系统和可行的协同调节可能指导和促进基于ESIONP的刺激响应性CA的开发，用于高度敏感和特异的肿瘤诊断。
Extremely small iron oxide nanoparticles (ESIONPs), as a kind of the special T1 magnetic resonance imaging (MRI) contrast agent that can provide T1 contrasting enhancement since their magnetically disordered shells are dominant compared to their magnetic cores and have powerful potential for constructing stimuli-responsive contrast agents (CAs) to realize precise the tumor diagnosis with high specificity and sensitivity. The stimuli-responsive function of ESIONPs-based CAs can be directly endowed through the synergistic regulation of the longitudinal and transverse relaxivity (r1 and r2) of ESIONPs. However, the systematical investigation for the synergistic regulation of r1 and r2 of ESIONPs is quite lacking. Herein, based on the relaxivity theories, three kinds of ESIONPs-based nanoassemblies with pH-responsiveness were designed and constructed to explore the possibility of various synergistic regulations on r1 and r2. When three kinds of ESIONPs-based nanoassemblies were converted to dissociated ones under a weak acid environment, ESIONPs micelle could realize a synergistic regulation of the single r2 decrease along with the stable r1, while gold nanoparticles-ESIONPs (AuNPs-ESIONPs) vesicle could provide a synergistic regulation comprising the single r1 increase along with the stable r2, and ESIONPs vesicle could offer a synergistic regulation involving the r2 decrease together with the r1 increase. Moreover, all the synergistic regulations on r1 and r2 were efficient strategies to fabricate ESIONPs-based CAs with the stimuli-responsive function. These systematic and feasible synergistic regulations of r1 and r2 may guide and promote the development of ESIONPs-based stimuli-responsive CAs for the highly sensitive and specific tumor diagnosis.