Synthesis, Application Of Fluorescence Switch And Synthesis, Characterization Of Self-assembly Of Anticancer Drug For Overcoming MDR

Fluorescent probe analysis technology has been widely noted because of its high sensitivity, good selectivity, detection convenient, and low detection limit microanalysis techniques. In recent decades, the fluorescent molecular probe technology in environmental science, medicine and life sciences analysis and detection in large numbers and rapid development.In this dissertation, we developed a new fluorescence probe Ac-SAACQ-Gly-Gly-Gly-Lys (FITC) for sequentially and selectively sensing Cu2+and L-histidine (L-His) in vitro and in living cells for the first time. The new probe has good water-solublility and cell-permeablility because of the existence of Gly-Gly-Gly-Lys. The SAACQ motif used for Cu2+chelation clawer and the fluorescein isothiocyanate (FITC) used as fluorescence resource in the probe. The fluorenscence of probes can be quenched via PET mechanism after Cu2+chelation. Finally, we sucessfully achieved the sequentially and selectively sensing Cu2+and L-His in vitro and in living cells.Site-specific labeling of proteins is an important approach for direct visualization of protein expression, association, and translocation, understanding the spatial and temporal underpinnings of life inside cells. In the past decade, genetically encoded fluorescent proteins (FPs) have been widely used to label their fusion proteins with absolute specificity and spatial resolution. However, they have intrinsic shortcomings such as high molecular weight and insensitivity to cellular environment. The chemical probes for visualization of the proteins had been developed to improve the labeling efficiency.In this dissertation, we made the advantage of condensation reaction between the1,2-aminothiol group of cysteine (Cys) and the cyano group of2-cyanobenzothiazole (CBT), and finally applied the condensation reaction to molecular imaging by optimalizing the substrate. In our experiment, we realized the labeling of Cys residues on proteins of chicken eggshell membrane (ESM) by combining these two biocompatible reactions (nucleophilic addition between thiol and maleimide, and condensation between CBT and N-terminal Cys).Multidrug resistance (MDR) is the major factor in the failure of large forms of chemotherapy in cancer patients. The MDR induced the tumor cells become more and more refractory to not only its own target drugs, but also some unrelated drugs that with different chemical structures or functionalized mechanisms. Nowadays, MRD becomes a big abstacle for the cancer treatment. The development of nano-drug delivery systems made significant breakthrough for overcoming the MRD.In this dissertation, we rationally designed four anticancer drugs1,2,3and its scramble probe3-Scr.2is a doxorubicin (DOX) derivative chemotherapeutic drug. And the other are taxol derivative chemotherapeutic drugs.1,2, and3contained a Arg-Val-Arg-Arg (RVRR) peptides sequence which can be specifically recognized and cleaved by furin. And RVRR sequence has a good water-solubility and cell-permeable. After furin cleavaged and reduction, the condensation reaction would be happened. The intracellular self-assembly of nanoparticals were formed and enhanced the concentration of chemotherapeutic drugs.