本研究結合奈米合成技術及生物醫學應用，以微波輔助加熱法合成碳量子點，並藉由調控異原子摻雜及改變純化方法，成功製備出紅、黃、綠及藍色螢光之碳量子點，擁有合成時間短、低毒性、良好的水分散性及生物相容性等優勢，並將之應用於抗氧化檢測及細胞螢光顯影，賦予碳量子點新穎特性。
第一部分：PMn@Cdots及PMn@Cdots–HA之抗氧化活性應用
以對苯二胺為碳前驅物，選擇磷(phosphorus，P)摻雜以提高其螢光量子產率，而錳(mangnese，Mn)摻雜則賦予碳量子點磁性特徵，利用微波輔助加熱法成功製備出紅色螢光碳量子點。而本研究針對PMn@Cdots進行抗氧化檢測之應用，分別利用DPPH、•OH及O2－•測定其抗氧化效果，而與抗壞血酸相比，證實PMn@Cdots亦具備有良好的抗氧化活性。再進一步將PMn@Cdots-HA應用於體外細胞，藉由H2O2作為活性氧來源對細胞造成氧化損傷，發現經PMn@Cdots-HA培養後之細胞能夠有效抵抗H2O2所造成的傷害，再次驗證其優異的抗氧化特性。
第二部分：N、S、P摻雜可調性螢光碳量子點之合成(P@Cdots、NS@Cdots、NSP@Cdots)
同樣以對苯二胺作為碳前驅物，利用GSH之氮(nitrogen，N)、硫(sulfur，S)原子與磷(phosphorus，P)原子作為摻雜來源，藉由微波輔助加熱法成功製備出紅、黃及綠色螢光碳量子點，再進一步使用矽膠管柱層析純化法分離出不同顏色碳量子點，並探討其光學性質變化及碳量子點發光機制。而經由體外細胞毒性測試證實本研究所製備出之碳量子點為低毒性材料，並將之應用於細胞螢光顯影，可證實NS@Cdots及NSP@Cdots不須經由表面功能化修飾即可藉由胞飲作用進入細胞而達到良好的螢光顯影效果。

Herein, we combined with nano-synthesis technology and biomedical applications. We present an aqueous based facile microwave-assisted synthesis of carbon quantum dots, which has short synthesis time, low toxicity, water dispersibility and biocompatibility. These advantages are beneficial for biological application. The red, yellow, green and blue fluorescent carbon dots were successfully synthesized by adjusting the heteroatomic doping and changing the purification method. Furthermore, we applied these carbon dots for in vitro antioxidant activity and bioimaging.
Part Ⅰ: Antioxidant activity of phosphorous and manganese element co-doped red magnetofluorescent carbon dots
P-phenylenediamine was used as carbon precursor. Doping phosphorous (P) heteroatom into Cdots could enhance the quantum yield. Furthermore, doping manganese (Mn) could impart magnetic property to carbon dots. The red fluorescent carbon dots were successfully synthesized by one-pot microwave method. In this study, the application of antioxidant property for PMn@Cdots was carried out by using DPPH, •OH and O2-•, respectively. The result was compared with ascorbic acid and it showed that PMn@Cdots also have good antioxidant property. Furthermore, in the protective activity result of H2O2-induced cell death model, it was found that PMn@Cdots-HA could reduce intracellular ROS levels and protect cells from oxidative stress.

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