栓塞治療術為一種微創手術，將栓塞物藉導管經由肝動脈引導至腫瘤位置，並將供應腫瘤血液的肝動脈以栓塞物如含化療藥物之栓塞微球等注入，以提供腫瘤細胞最大劑量的局部治療。本研究探討壓電式單粒徑產生技術，目標為生產粒徑範圍介於250 於圍介於為生產粒徑範圍的微球，以因應醫療用栓塞劑之需求。本研究之壓電式單粒徑產生裝置，係利用注射幫浦將工作流體注入噴嘴內，施以正弦波之外部激擾，使液柱在擾動下形成單粒徑液滴。本研究所採用之工作流體包含甘油混合溶液、醫療用栓塞劑配方及硬脂酸等材料。首先以甘油混合溶液做噴嘴性能測試及造粒參數研究，透過無因次參數分析，找出適用於單粒徑造粒之經驗公式，接著將其運用於醫療用栓塞劑之噴霧造粒實驗，並分析造粒後之微球粒徑分布。實驗結果顯示，工作流體在激擾頻率1.0 kHz ~ 10.5 kHz區間內，皆可產生單粒徑液滴，其粒徑隨頻率增加而下降，在此區間外則為多粒徑液滴產生區。工作流體之黏度在35.2 cP~ 80.3 cP間，對於液滴粒徑影響不顯著。實驗結果亦顯示，工作流體之表面張力在38.0 ×10-3N/m ~ 67.1 ×10-3 N/m間，對於液滴粒徑影響亦不顯著。主要影響液滴粒徑之參數為激擾頻率、液柱速度及噴口孔徑，進一步整理可知，液滴粒徑與孔徑比(dp/do)隨史卓荷數(St)增加而下降，產生之單粒徑液滴之粒徑為孔徑之1.8~3.4倍，因此可得液滴粒徑與孔徑比對史卓荷數之經驗公式。進一步使用醫療用栓塞劑作為工作流體進行噴霧造粒，實驗結果顯示，自行設計之冷卻艙之冷卻效果相當良好，收集到之顆粒皆為硬化之球型粒子，本系統可成功製造單粒徑醫療用栓塞微球及硬脂酸微球，其平均粒徑分別為330.2別為別為球，其平均粒徑分及314.6 為別為球，其平均粒徑分別，適用於醫療栓塞之需求。

Transcatheter arterial chemoembolization is a minimally invasive surgical treatment. A catheter is introduced through the abdominal aorta into the target hepatic artery. The particles containing chemotherapy agent is injected through the catheter to the tumor at the selected blood vessel location. It would result in removal of the cancer cells in the treatment process. This research aims at the development of a piezoelectric monodipersed particle generation system for the production of medical embolization microspheres. The laminar fluid stream issued from the monodipersed particle generation nozzle is disintegrated to monodispersed particle under excitation within a frequency range while non-uniform droplet would be produce out of this range. The performance of monodipersed particle generation nozzle was first characterized by glycerin mixture. Then, the generation of the medical embolization microspheres and stearic acid microspheres was performed. Results show that the particle size is decreased as the excitation frequency is increased. Furthermore, the particle size is increased as the Reynolds number of the working fluid was increased. Results show that the effects of Surface tension of the working fluid within the range of 38.0 ×10-3 N/m to 67.1 ×10-3 N/m to particle size is insignificant. In addition, the viscosity of the working fluid within the range of 35.2 cP to 80.3 cP has little effect on particle size. It is concluded that the particle size can be controlled effectively by increasing excitation frequency and reducing nozzle orifice as well as Reynolds number. Dimensional analysis indicates that the ratio of particles mean diameter and orifice diameter is a function of Strouhal number. It can be expressed in terms of an empirical formula. It turns out that the particles diameter of the glycerin mixture is 1.8~3.4 times of the orifice diameter. In the test using medical embolization material and stearic acid, the bead size is 330.2 μm± 24.0 μm and 314.6 μm ± 16.1 μm, respectively. The bead shape is highly spherical and hence is suitable for medical embolization applications

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