Hairy Hybrid Microrattles of Metal Nanocore with Functional Polymer Shell and Brushes
Hairy Hybrid Microrattles of Metal Nanocore with Functional Polymer Shell and Brushes
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DOI：
10.1021/ma200102n
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发表时间：
2011-03
期刊：
影响因子：
5.5
通讯作者：
Guoliang Li;L. Xu;K. Neoh;E. Kang
中科院分区：
文献类型：
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作者：
Guoliang Li;L. Xu;K. Neoh;E. Kang
空心微球和纳米球因其在药物封装、电子元件的换能器和电介质、催化反应和储氢胶囊等方面的相关应用而受到广泛关注。[17]各种化学和物理化学方法，如硬模板法和软模板法，嵌段共聚物的自组装和无模板合成，已经发展到生产无机，聚合物和杂化中空颗粒。在目前报道的各种方法中，模板定向合成可能是最广泛使用的方法，用于生成具有精确控制尺寸和壳厚的空心颗粒。该过程通常包括通过化学溶解去除硬模板芯9,13或通过热分解从外壳前体中去除软模板芯。此外，这些中空微球或纳米球的形态、表面功能、尺寸和尺寸分布的调节总是需要提高它们在实际应用中的性能，例如在药物输送系统（DDS）中。通过内部空隙空间和/或外壳表面的后处理来功能化聚合物空心微球是非常理想的。一方面，室内空间的功能化可以通过客人物种的封装来实现。14r17在中空腔中包裹可移动金属芯的无机中空颗粒，被称为“蛋黄壳”或“摇铃型”结构，已被广泛报道。18r21除了具有明确的中空结构外，响尾针型无机颗粒在催化反应中也表现出改善/增强的活性，并可作为磁共振成像（MRI）的造影剂。21另一方面，通过噻吩化学反应进行的外表面改性效率很高，没有副产品，也不需要有毒过渡金属作为催化剂。22r34近年来，噻吩点击化学已被用于构建新的大分子结构和硅衬底、30聚合物纳米颗粒、31、32和蛋白质固定化生物芯片的“点击”功能化。33,34在本文中，我们描述了一种毛状摇铃型杂化微球的合成路线，该微球由金属纳米核（金或银）、聚（甲基丙烯酸-共二乙烯基苯）（P (maa -共dvb)）外壳和外表面的功能性聚合物刷组成。利用金@二氧化硅或银@二氧化硅覆盖壳纳米粒子作为模板，形成金属@二氧化硅@聚合物覆盖双壳微球，从而实现了金属纳米核的结合。巯基端亲水聚乙二醇（PEG-SH）的聚合物链或
Hollow micro-and nanospheres have received considerable attention because of their relevant applications as drug encapsulates, as transducers and dielectrics for electronics, and as capsules for catalytic reactions and hydrogen storage. 1r7 A variety of chemical and physicochemical approaches, such as hard and soft template approaches, self-assembly of block copolymers, and template-free synthesis, have been developed to produce inorganic, polymer, and hybrid hollow particles. 8r13 Among the various approaches reported so far, template-directed synthesis is probably the most widely used method for the generation of hollow particles with precisely controlled size and shell thickness. The process generally involves the removal of either the hard template core by chemical dissolution9, 13 or soft template core by thermal decomposition from the corershell precursors. 10 Moreover, regulation of morphology, surface functionality, size, and size distribution of these hollow micro-or nanospheres is always required to improve their performance in practical applications, such as in drug delivery systems (DDS). 4 It is highly desirable to functionalize the polymer hollow microspheres through postmodification of interior void space and/or exterior shell surfaces. On one hand, functionalization of the interior void space can be achieved by encapsulation of guest species. 14r17 Inorganic hollow particles encapsulating a movable metal core in the hollow cavity, termed the “yolkrshell” or “rattle-type” structure, have been widely reported. 18r21 In addition to the well-defined hollow structures, rattle-type inorganic particles also exhibit improved/enhanced activity in catalytic reactions20 and can serve as contrast agents in magnetic resonance imaging (MRI). 21 On the other hand, exterior surface modification via the thiolrene click chemistry is highly efficient, free of byproduct, and does not require toxic transition metals as catalyst. 22r34 The thiolrene click chemistry has recently been explored for the construction of novel macromolecular architectures and for “click” functionalization of silicon substrate, 30 polymer nanoparticles, 31, 32 and protein-immobilized biochips. 33, 34In this paper, we describe a synthesis route to hairy rattle-type hybrid microspheres consisting of a metal nanocore (gold or silver), a poly (methacrylic acid-co-divinylbenzene)(P (MAA-co-DVB)) shell, and functional polymer brushes clicked on the exterior surface. The incorporation of metal nanocore was achieved by using the gold@ silica or silver@ silica corershell nanoparticles as templates for the formation of metal@ silica@ polymer corerdouble shell microspheres. The thiol-terminated polymer chains of hydrophilic poly (ethylene glycol)(PEG-SH) or