Tang Junyun, Mi Jiaomei, Huang Wenwei, Zhong Huixiang, Li Yan, Zhou Jianhua, Johri Amer M
Department of Biomedical Engineering, School of Engineering, Sun Yat-sen University, Guangzhou 510275, China.
J Mater Chem B. 2018 Apr 7;6(13):1920-1929. doi: 10.1039/c7tb03164e. Epub 2018 Mar 5.
Ultrasound controlled drug delivery and release has attracted increased attention for targeted delivery of drug. In this report, we present a strategy for targeted drug delivery by using ultrasound to image the location of drug carriers, as well as simultaneously controlling the release rate of drug from elastic eccentric microcapsules (EEMs), based on their mode shapes (MSs) and resonant natural frequencies (NFs). We prepared a series of EEMs with various diameters of inner spherical cavities using a microfluidic chip. The EEMs could be visualized by an ultrasound imaging system within a tissue mimic (i.e. phantom). Using theoretical modeling techniques, we investigated the effects of MSs and NFs on the resonant modes of EEMs. Guided by this modelling, we applied external ultrasonic stimuli at various levels of low frequency to regulate the release rate of Rhodamine 6G (R6G, as a model drug) from EEMs. To further demonstrate the control of drug release and evaluate the efficacy of the encapsulated drugs on cancer cells, we released an anticancer drug, doxorubicin hydrochloride (DOX), from the EEMs and tested the viability of cancer cells in vitro. The results show that this novel strategy holds great promise towards development of a controlled drug release system visualized and triggered by ultrasound.
超声控制药物递送与释放已在药物靶向递送方面引起了越来越多的关注。在本报告中，我们提出了一种靶向药物递送策略，即利用超声对药物载体的位置进行成像，并基于弹性偏心微胶囊（EEMs）的振型（MSs）和共振固有频率（NFs）同时控制药物从EEMs中的释放速率。我们使用微流控芯片制备了一系列具有不同内径球形腔的EEMs。EEMs可以在组织模拟物（即仿体）中通过超声成像系统可视化。利用理论建模技术，我们研究了MSs和NFs对EEMs共振模式的影响。在此建模指导下，我们施加不同水平的低频外部超声刺激，以调节若丹明6G（R6G，作为模型药物）从EEMs中的释放速率。为了进一步证明对药物释放的控制并评估包封药物对癌细胞的疗效，我们从EEMs中释放了一种抗癌药物盐酸多柔比星（DOX），并在体外测试了癌细胞的活力。结果表明，这种新策略在开发由超声可视化和触发的可控药物释放系统方面具有很大的前景。
