溫度感應型水膠應用於聚焦型超音波熱治療之研究

THE APPLICATION OF THERMO-SENSITIVE HYDROGELS ON ULTRASOUND THERMAL THERAPY

蕭義正(Yi-Zheng Xiao)

指導教授 ： 郭鴻森 ； 李基禎

大同大學/工程學院/機械工程學系所/碩士(2007年)

摘要

根據研究顯示，當加熱溫度大於42℃時，每單位時間的細胞存活率會極劇的下降，也就代表腫瘤細胞的死亡率，跟溫度和加熱的時間有很大的關係，利用此一特性，將高強度聚焦型超音波的能量傳入人體體內，將目標區域的腫瘤細胞加熱，以達到治療的目的。
本研究建立一套超音波實驗系統，利用聚(氮－異丙基丙烯醯胺)poly(N-isopropyl acrylamide，NIPAAM)溫度感應型水膠，探討超音波在相同瓦數、相同時間，照射的焦斑大小與位置，因為溫度感應型水膠的特性，依焦斑的大小即可辨別特定溫度的分布範圍，本研究更在溫度感應型水膠中加入親水性單體丙烯酸(Acrylic acid，AAc)以提高其變色溫度，來觀察各種溫度的分布範圍，還有加入奈米金粒子，觀察添加奈米金粒子對於溫度感應型水膠有何影響，對焦斑大小和位置有何改變，綜合以上數據，可以給超音波熱治療手術前作參考，藉以提升手術的準確度。

關鍵字

丙烯酸 ； 氮－異丙基丙烯醯胺 ； 超音波熱治療 ； 奈米粒子

並列摘要

According to studying, to heat above 42℃ that the survival rate of a cell will decrease rapidly. It gives an evident description about the heat induced cell killing effect, which shows that cell killing is dependent on the temperature and the exposure duration. This treatment utilizes the highly focused ultrasonic energy to steer into human’s tissues. the temperature at the focal region can be raised. To reach the treatment’s objectives.
An ultrasonic experimental systems was built. We used Poly(N-isopropylacrylamide)(Poly(NIPAAm))thermo-sensitive hydrogels in reversible color change in response to small temperature changes around its low critical solution temperature (LCST). To found ultrasound of the lesion’s size and position when different time and power. By the lesion’s size, we can recognize the ultrasonic temperature distributions. We added Acrylic acid(AAc) for increase LCST. So we can recognize any ultrasonic temperature distributions. We added nanoparticles, in order to increase hydrogels of attenuation coefficient. The temperature distributions can improve ultrasound thermal therapy.

並列關鍵字

Acrylic acid ； N-isopropylacrylamide ； ultrasound thermal therapy ； nanoparticles

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