Oil-filled polymer microcapsules for ultrasound-mediated delivery of lipophilic drugs
Oil-filled polymer microcapsules for ultrasound-mediated delivery of lipophilic drugs
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DOI：
10.1016/j.jconrel.2008.09.085
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发表时间：
2009-01-19
影响因子：
10.8
通讯作者：
van Wamel, Annemieke
中科院分区：
文献类型：
--
作者：
Kooiman, Klazina;Bohmer, Marcel R.;van Wamel, Annemieke
超声造影剂作为局部给药系统的应用在不断发展.目前的限制是可以掺入的药物的量以及声穿透时药物释放的效率。本研究的重点是合成和表征的新型聚合物微囊超声触发亲脂性药物的传输。用预混膜乳化法制备了以氟化封端的聚乳酸为壳的微胶囊，微胶囊中除气相外还含有不同量的十六烷油作为药物载体。平均数加权直径在1.22 μ m和1.31 μ m之间。以类似于每秒1000万帧的高速成像显示，对于低声压（1 MHz，0.24MPa），微胶囊被压缩但保持完整。在0.51 MPa的较高诊断压力下，微胶囊破裂，从而释放出封装的气体和模型亲脂性药物，在2.5 MHz的频率下的U-Sing常规超声B模式成像，对于所有不同加载的微胶囊，观察到在组织模拟体模上散射强度的显著增强。部分充油微囊具有高载药量和明确的声激活阈值，在超声图像引导下超声触发亲脂性药物局部给药方面具有很大的潜力。(C)2008 Elsevier B. V.保留所有权利。
The use of ultrasound contrast agents as local drug delivery systems Continues to grow. Current limitations are the amount of drug that can be incorporated as well as the efficiency of drug release Upon insonification. This Study focuses oil the synthesis and characterisation of novel polymeric microcapsules for ultrasound-triggered delivery of lipophilic drugs. Microcapsules with a shell Of fluorinated end-capped poly(L-lactic acid) were made through pre-mix membrane emulsification and contained, apart from a gaseous phase, different amounts of hexadecane oil as a drug-carrier reservoir. Mean number weighted diameters were between 1.22 mu m and 1.31 mu m. High-speed imaging at similar to 10 million fames per second showed that for low acoustic pressures (1 MHz, 0.24 MPa) microcapsules compressed but remained intact. At higher diagnostic pressures of 0.51 MPa, microcapsules cracked, thereby releasing the encapsulated gas and model lipophilic drug, U-Sing conventional ultrasound B-mode imaging at a frequency of 2.5 MHz, a marked enhancement of scatter intensity over a tissue-mimicking phantom was observed for all differently loaded microcapsules. The partially oil-filled microcapsules with high drug loads and well-defined acoustic activation thresholds have great potential for ultrasound-triggered local delivery of lipophilic drugs under ultrasound image-guidance. (C) 2008 Elsevier B.V. All rights reserved.