癌症於臨床上的主流治療方法可分為三種，分別是手術切除、放射線治療以及化學治療。當癌細胞還未擴散時，直接經由手術切除腫瘤部位或使用高能量的放射線毒殺癌細胞，都有良好的治療效果；而當癌症擴散後，則需進行全身性化學治療，將抗癌藥物經由口服或靜脈注射投藥，使藥物經由血液循環到達癌症部位，進行毒殺癌細胞作用。於臨床上常見的抗癌藥物像是阿黴素(Doxorubicin)，俗稱小紅莓，因為它對於多種癌症皆有治療效果所以被廣泛使用，但其所伴隨的嚴重副作用則是會造成心臟衰竭。為了解決上述所遭遇到的問題，許多團隊研發將Doxorubicin包覆於微脂體內部，降低對心臟的傷害，像是市售藥物Doxil®或是ThermoDox®，但是Doxil®的藥物釋放速率慢，藥物無法有效的被釋放出來；而ThermoDox®雖然可以藉由局部升溫刺激微脂體有效釋放藥物，但在血液循環中無法保持穩定。為了進一步克服市售藥物所面臨到的問題，本研究提出利用微脂體包覆具有溫度敏感性的碳酸氫銨(ammonium bicarbonate)與抗癌藥物Doxorubicin，於37℃下保持穩定，但是在局部升溫至42℃時，包覆於微脂體內的碳酸氫銨遇熱會迅速分解成氨、水以及二氧化碳氣體，此時產生的二氧化碳氣體會干擾微脂體脂質雙層的穩定性，使包覆於微脂體內的藥物快速釋放出來，達到毒殺癌細胞之效用。碳酸氫銨也可藉由主動載藥法(remote-loading)將Doxorubicin包覆在微脂體的親水核心，由實驗結果可以得知，其Doxorubicin包覆率可達到93.8%。因此，本實驗開發的藥物載體不僅可穩定包覆藥物，並且在局部升溫時，包覆於微脂體內部的碳酸氫銨會快速分解產生二氧化碳干擾微脂體穩定性，利於藥物釋放達到治療效果。

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