Stable incorporation of gold nanorods into N-isopropylacrylamide hydrogels and their rapid shrinkage induced by near-infrared laser irradiation
Stable incorporation of gold nanorods into N-isopropylacrylamide hydrogels and their rapid shrinkage induced by near-infrared laser irradiation
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DOI：
10.1021/la0627967
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发表时间：
2007-03-27
期刊：
影响因子：
3.9
通讯作者：
Katayama, Yoshiki
中科院分区：
文献类型：
--
作者：
Shiotani, Atsushi;Mori, Takeshi;Katayama, Yoshiki
在这项研究中，我们制备了金纳米棒（NR）嵌入N-异丙基丙烯酰胺（NIPAM）水凝胶，并研究了其体积相变行为诱导近红外（近红外）激光照射利用光热转换特性的NR。当聚（乙二醇）改性的NR用于制备复合凝胶，NR在凝胶中表现出显着的分散稳定性。在下列条件下，凝胶中NR浓度≥ 100 μ M和激光辐射功率≥ 490 mW，用近红外激光辐射凝胶（圆柱形，直径= 140 μ m），导致凝胶以下列方式收缩：（1）在辐射点周围形成腰部和（2）腰部沿着凝胶的轴向生长。由近红外辐射引起的凝胶收缩发生得比由温度跳变所提供的要快得多，因为前者不伴随着皮肤层的形成，这干扰了凝胶的快速收缩。当用近红外激光照射含有模型药物（罗丹明标记的葡聚糖）的复合凝胶时，观察到药物的快速释放。利用辐射点的高空间分辨率，我们进一步实现了药物从一个这样的凝胶的辐射点特定的释放。
In this study, we prepared gold nanorod (NR)-embedded N-isopropylacrylamide (NIPAM) hydrogels and studied their volume phase transition behavior induced by near-infrared (near-IR) laser irradiation utilizing the photothermal conversion characteristics of the NRs. When poly(ethylene glycol)-modified NRs were used for the preparation of composite gels, the NRs showed marked dispersion stability in the gel. Near-IR laser irradiation of the gel (cylindrical shape, diameter = 140 mu m) under the following conditions, NR concentrations in the gel >= 100 mu M and laser irradiation power >= 490 mW, resulted in shrinkage of the gel in the following manner: (1) waist formation around the irradiation spot and (2) growth of the waist along the axial directions of the gel. The gel shrinking induced by near-IR irradiation occurred much more rapidly than that afforded by a temperature jump, because the former was not accompanied by the skin layer formation, which disturbs the rapid shrinking of the gels. When a composite gel containing the model drug (rhodamine-labeled dextran) was irradiated with a near-IR laser, the rapid release of the drug was observed. Taking advantage of the high spatial resolution of the irradiation point, we further achieved the irradiation-point-specific release of the drug from one such gel.