| This thesis mainly deals with two parts of work:1) the development and application of cisp latin probe;2) the design and discussion of arsenic probe;Cisplatin has been widely used for treating solid tumours, such as germ cell tumours, carcinomas of the head and neck and other tumour types. However, cisplatin administration has frequently shown toxic side effects, including nephrotoxicity, neurotoxicity and the induction of nausea and vomiting. The dosage control of cisplatin is a key factor in the successful execution of cisplatin-based chemotherapy. Thus, the fast, convenient detection methods for cisplatin are highly desirable. Based on the interaction of cisplatin with G-quadruplex DNA, we developed a simple label-free fluorescence method for rapid cisplatin detection. The self-folding of PS2.M (G-quadruplex DNA) without cisplatin would form a G-quadruplex DNA structure that binds NMM and results in a remarkable hyperchromic effect. When cisplatin was added, it would bind to PS2.M and disintegrate the DNA structure of the G-quadruplex, which would result in an obvious hypochromic effect. The titration experiment showed that the cisplatin concentration and the fluorescence signal change ratios (Fo/F) exhibited a consistent linear correlation within the1to10μM range with a limit of detection of720nM, which was even lower than the common concentration of cisplatin in chemotherapy patients’ urine (54.3to321μM). The KD for cisplatin binding was determined to be1.28×10-5M on the basis of the fitting of the curve. We demonstrated the high sensitivity of this methodology in the direct detection of cisplatin in urine samples and the fluorescence imaging of free cisplatin in living cells. Arsenic can make people to death, as a kind of harmful substances and can asb be used as a drug to treat leukemia, depending on the dose of arsenic. Therefore, the detection of arsenic is important to improve the curative effect of arsenic and avoid arsenic poisoning. We developed a new method for detection of arsenic through the FRET technology, based on PML protein. Unfortunately, the result was not ideal in actual measurement. Next, we changed all kinds of variations of PML and tried several experimental conditions, but the result was still not obvious. We found that the probe had no response to arsenic in the process of measurement, but had a good response to zinc ions in both sensitivity and selectivity. Therefore, we developed a sensor to detect zinc ion successfully. The significance of this paper also reflected in providing some experience in arsenic probe designing. |
