Synthesis And Application Of Fluorescent Dyes For Nucleic Acid Detection And Mitochondria Imaging

With rapid development of bio-imaging technology in recent years, fluorescent dyes have been increasingly used in cell labeling and imaging, protein analysis, DNA sequencing, medical diagnostics, bio-sensing and other research fields. Cyanine dyes have excellent spectral performance and can be synthesized and purified easily. Therefore they have drawn great attention of lots of researchers.Nucleic acid is the carrier of genetic information and material basis of gene expression, which is of great importance in growth, development, reproduction and other normal bioactivities of species. Meanwhile, changes in nucleic structure are closely related to abnormalities in bioprocess, such as genetic disease, cancer, radioactive damage and so on. So it is significant to lucubrate the structure and function of nucleic acid and its interactive model and characters with various organic and inorganic molecules. MT-SYBR synthesized in this assay is barely fluorescent in aqueous solution, but emits strong fluorescence (Quantum Yield=0.509) after bonding with DNA. The detection limit of MT-SYBR to DNA is as low as0.47ng/mL with a linear range of0-1800ng/mL. Further tests show the fluorescent emission of MT-SYBR increased550folds in5s upon bonding with saturated DNA solution. Moreover, MT-SYBR is membrane-permeable and proved having value in live-cell nuclei imaging.Mitochondria have roles in a variety of vital cellular processes, such as storing calcium and cooperating with endoplasmic reticulum to maintain the balance of calcium concentration in cells, regulating apoptotic cell death and so on. Mitochondria are particularly sensitive to a number of damaging influences. Changes in the number, size and structure of mitochondria are often observed in the patients from Alzheimer’s disease to cancer. Nowadays, fluorescent dyes used for imaging mitochondria are often seen in cyanine and rhodamine frameworks. To enrich the varieties of dyes for mitochondria imaging, DM-BAT was synthesized. The results show DM-BAT barely emits fluorescence in vitro, and is insensitive to pH and polarity changes. It’s mitochondria-targeted and suffer little from membrane-potential through the co-staining with commercial mitochondria-staining dye and membrane-potential experiments.