超音波調控藥物傳遞的發展，使超音波對比劑不再只作增強影像對比之用，更可視為藥物載體進行治療。相變液滴(Droplets)經由超音波將內部包覆低沸點之液相全氟碳化合物汽化，並轉變成微氣泡之現象稱為acoustic droplet vaporization (ADV)。經由上述汽化過程所引發之震盪，促使液滴殼層破裂，將藥物進行釋放，並同時增強超音波影像之對比。然而近來許多文獻已指出，幹細胞具有腫瘤趨向之特性，故將幹細胞作為奈米藥物載體極具發展的潛力。其中奈米相變液滴(Nanodroplets, NDs)即為一良好奈米載體，但超音波激發奈米相變液滴汽化之聲學閾值，卻會隨著液滴粒徑越小而提升，增加超音波汽化的困難、以及臨床應用的安全性考量。因此本研究藉由包覆藥物之融合式奈米相變液滴(Fusogenic drug-loaded NDs, FNDs)，承載於幹細胞後，於細胞體內產生融合特性，改善奈米相變液滴汽化之聲學閾值較高的問題，並達到目標區域藥物釋藥之目的。
包覆藥物之融合式奈米相變液滴是利用全氟戊烷、喜樹鹼(Camptothecin, CPT)和磷脂質所製備完成，按照特定脂質比例以增加融合性後，即對包覆喜樹鹼之融合式奈米相變液滴(CPT-FNDs)於粒徑變化前後，進行完整的特性量測。接著將CPT-FNDs與脂肪幹細胞(Adipose-derived stem cells, ADSCs)共培養後，進行脂肪幹細胞承載CPT-FNDs之數量、細胞存活率、及細胞移行能力等評估。最後利用2.0-MHz高能聚焦式超音波探頭(3 cycles, 12 MPa)激發承載於脂肪幹細胞中的CPT-FNDs，藉由高速攝影機觀察CPT-FNDs汽化現象和效率。將超音波照射前後之CPT-FNDs與脂肪幹細胞共培養的細胞溶液收集，加入小鼠黑色素瘤細胞細胞株(Melanoma cell, B16-F0)中共培養，量測脂肪幹細胞與腫瘤細胞於0、24小時的細胞活率，以評估激發汽化與釋藥毒殺之效果。
製備完成之CPT-FNDs其平均粒徑、包覆CPT藥物的能力，分別為381.6 ± 3.5 nm與0.48 mg/mL。於模擬活體體溫環境放置16 h後，CPT-FNDs之粒徑的確具有融合特性，從371.6 ± 3.5 nm增加至1043 ± 28 nm。並隨著粒徑的上升，超音波汽化效率也從22.1 ± 1.9%提升至37.6 ± 2.1%。另外，流式細胞儀的分析結果，可得到脂肪幹細胞承載量隨著加入之CPT-FNDs濃度、與加入之時間增加而提升。其細胞量也可從5.3%提升到97.1%的細胞皆有承載上CPT-FNDs。脂肪幹細胞承載CPT-FNDs後，雖然會造成細胞活性的降低(75.91 ± 5.29%)，但卻不顯著影響其細胞移行的能力(移行之細胞數約降低33%)。CPT-FNDs與脂肪幹細胞共培養後，經超音波激發汽化產生的微氣泡，不但具有增強超音波影像對比之能力(47.3 ± 0.5 dB)，其汽化過程也伴隨產生35%的細胞殺傷力。此外，經由超音波將脂肪幹細胞承載之CPT-FNDs汽化效率，會隨著CPT-FNDs與細胞共培養的時間增加而降低；但與細胞體內CPT-FNDs之粒徑增加而提升。最後藉著超音波激發細胞承載之CPT-FNDs汽化，綜合物理性ADV效應、以及藥物釋放的化學效應，可以對癌細胞產生69%的毒殺效果。
結果顯示以脂肪幹細胞承載包覆藥物之融合式奈米相變液滴，作為藥物傳遞載體，於腫瘤局部釋藥上具發展的潛力。未來可將此治療方式實際應用於腫瘤動物模型上，觀察承載CPT-FNDs之脂肪幹細胞於活體中展現腫瘤趨向性，並予以超音波激發汽化，達到局部釋放藥物進行治療之成效。

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