碳量子點是一種新型的零維奈米材料，由於普遍具有良好的螢光特性和生物相容性，在生物顯像的領域受到廣泛的應用。本研究我們以檸檬酸和三乙烯四胺為前驅物，並利用微波法合成氮摻雜碳量子點。在應用方面，第一，不同的酸鹼環境影響下，其螢光強度隨著pH值有良好的線性關係；第二，針對不同的金屬離子溶液，發現對六價鉻離子有明顯的專一性螢光消逝；第三，我們也透過碳量子點做大腸桿菌的細胞標記，發現有良好的螢光強度和生物相容性。我們利用大腸桿菌BL21將Pb5蛋白大量表現純化後以螢光基團修飾，藉由噬菌體Pb5蛋白和大腸桿菌外膜蛋白的結合特性，作為標記大腸桿菌的方式，也發現對於大量表現FhuA外膜蛋白的大腸桿菌可作為良好的專一性螢光探針。再者，我們能以螢光訊號的強度來呈現不同細菌量對於修飾過的Pb5蛋白結合情況，發現有良好的線性關係。最後，我們利用偵測在細胞裂解產物的上清液螢光訊號，定量細胞裂解的效率。

Carbon quantum dot is a type of zero-dimensional nanomaterials. These materials have been widely applied to bioimaging and sensor to their outstanding properties such as fluorescence and biocompatibility. In this study, water-soluble N-doped carbon quantum dots (CQDs) were synthesized by microwave-induced decomposition using citric acid and triethylenetetramine (TETA) as precursors. For the applications, firstly, the intensity of fluorescence showed linear relationship with pH values. Secondly, these CQDs were sensitive fluorescent probes for the detection of Cr6+ with significant fluorescence quenching. Thirdly, we found the excellent properties of cell imaging and biocompatibility on labeling E. coli with CQDs. We labeled the E. coli outer membrane with the strong interactions between the bacteriophage tail protein Pb5 which was modified with rhodamine and E. coli outer membrane protein ferric hydroxamate uptake A (FhuA). Besides, we could estimate the number of the cells based on the linear relationship between the fluorescence signals of modified Pb5 and the cells. Finally, the protein complexes, FhuA-Pb5-rhodamine, was used to estimate the efficiency of cell lysis.

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