| The detection of oxygen based on room-temperature phosphorescence (RTF) methodology is a simple, sensitive and rapid method, which is booming recently. Compared with traditional oxygen detection methods, there are several advantages using this sensor: No oxygen consumption and reference electrode are needed; no electronic current is needed and no disturbances happen if there is a magnetic field outside; the intensity of the phosphorescence hasn't relation to the stir and flow rate of the sample; the response is rapid. Recently, the study of phosphorescence sensors is arousing great interest.Herein a detailed summarization is given on the development of RTF oxygen sensors, the common sensor types and applications to such aspects as biology, environment protection, medicine and hygiene.We used palladium porphyrins as phosphorescence dictators. They could be bound to suitable carriers and emit strong phosphorescence at room temperature. Oxygen molecules can easily quench phosphorescence signals. According to this characteristic, we can monitor the oxygen concentration in both the gas mixture and water. Three porphyrin complexes of palladium were chosen as phosphorescence sensing molecules: palladium-meso-tetra (trimethylaminophenyl) porphyrin (Pd-TAPP), palladium-coporphyrin (PdCP) and palladium-meso-tetra (p-sulfonicphenyl) porphyrin (Pd-TSPP). They were bound to Dowex resins, and made into oxygen sensor. We detected the characteristics such as sensitivities and response times combined with flow injection analysis (FIA) technology. When the sensors were applied to real samples, the detection results were satisfactory.Chapter 1: In this chapter, we mainly reviewed the history and development of RTF methodology. The principles of the oxygen sensor have also been discussed.Chapter 2: RTF methodology is a well-established detection technology for oxygen both in gas mixture and in solutions based on the signals quenching. Because of theexceptional analytical features of the RTF technology, the high sensitivity, specific selectivity and the low cost of the necessary instrumentation, the optical sensors based on RTF have a highly attractive and promising future.A review of the literatures on optical oxygen sensors is present here. The brief introduction, the configuration, the dyes, the matrixes and the immobilization technology are discussed along with the application of oxygen detection.Chapter 3: The dye Pd-TAPP was covalently bound to Dowex50X2-100 resin by the electrostatic interaction. The phosphorescence of the resulted material is extremely quenched by oxygen and the resulting material can be used as a useful probe for the measurement of oxygen in gas mixture. The photochemical properties and the analytical performances of the RTP probe were studied by using a gas flow-injection analysis (gFIA) system, which incorporated a convenient exponential dilution chamber for gas sample introduction. It was shown that the sensor had merits of rapid response (typical response times were 18s from N2 to O2 stream and 86s from O2 to N2 stream for 95% signals change), high precision (2.7%o at 0.6% O2 (v/v) level) and low detection limit (0.09%O2(v/v)).Chapter 4: The dye PdCP has been bound to Dowexl X 2-200 resin mainly by the electrostatic interaction. The resulting material could be extremely quenched by oxygen and is a useful probe for the measurement of oxygen in gas and liquid samples. The photochemical properties and the analytical performances of the RTP probe have been studied by using a gFIA system, which incorporated a convenient exponential dilution chamber for gas sample introduction. We also performed an experiment on this sensing material to measure dissolved oxygen by using a peristaltic pump. It was shown that the sensor had rapid response (Typical response times were 30s from N2 to O2 stream, 96s in verse and 108s from deoxygenate liquid to water, 300s in verse for 95% signals change) high precision (1% for gas mixture and 1.8% for dissolved oxygen) and low detection limit (13ug...
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