Key Laboratory of Mesoscopic Chemistry (Ministry of Education), State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, and School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210023, P. R. China.
ACS Appl Mater Interfaces. 2017 Jun 14;9(23):19638-19645. doi: 10.1021/acsami.7b04015. Epub 2017 May 31.
To explore the diversity and promising applications of pillararene-based molecular machines, phosphonated pillar[5]arenes (PPA[5]) were synthesized to construct novel supramolecular nanovalves for the first time, based on mesoporous silica nanoparticles (MSNs) functionalized with choline and pyridinium moieties, respectively. PPA[5] encircled the choline or pyridinium stalks to construct supramolecular nanovalves for encapsulation of drugs within the MSN pores. PPA[5] showed a high binding affinity for the quaternary ammonium stalks through the host-guest interactions primarily via ion pairing between the phosphonate and quaternary ammonium moieties, in comparison with carboxylated pillar[5]arene (CPA[5]), to minimize premature drug release. The specific ion pairing between the phosphonate and quaternary ammonium moieties was elaborated for the first time to construct supramolecular nanovalves. The supramolecular nanovalves were activated by low pH, Zn coordination, and competitive agents for controlled drug release, and release efficiency and antitumor efficacy were further enhanced when gold nanorod (GNR)-embedded MSNs (GNR@MSNs) were used instead under illumination of near-infrared (NIR) light, attributed to the synergistic effect of photothermo-chemotherapy. The constructed PPA[5]-valved GNR@MSN delivery system has promising applications in tumor photothermo-chemotherapy.
为了探索基于杯芳烃的分子机器的多样性和广阔应用前景，我们首次合成了膦化杯[5]芳烃（PPA[5]），基于分别用胆碱和吡啶基团功能化的介孔硅纳米粒子（MSNs）构建了新型超分子纳米阀。PPA[5]环绕胆碱或吡啶支链构建超分子纳米阀，用于将药物封装在 MSN 孔内。与羧基化杯[5]芳烃（CPA[5]）相比，PPA[5]通过主客体相互作用（主要是通过磷酸酯和季铵部分之间的离子配对）对季铵支链表现出高结合亲和力，以最小化药物的过早释放。首次详细阐述了磷酸酯和季铵部分之间的特定离子配对，以构建超分子纳米阀。超分子纳米阀可通过低 pH 值、Zn 配位和竞争性试剂激活，以进行控制药物释放，当使用嵌入金纳米棒（GNR）的 MSNs（GNR@MSNs）代替时，在近红外（NIR）光照射下，释放效率和抗肿瘤功效进一步增强，归因于光热化疗的协同效应。构建的 PPA[5]阀控 GNR@MSN 递药系统在肿瘤光热化疗中有广阔的应用前景。
