Research Of Spectrometer Based On Liquid Core Waveguide And Applied Study Of In-tube Solid Phases Microextraction Combined With Liquid Chromatography

Using liquid-core waveguide as a detection pool is considered as an effective manner to improve the sensitivity of spectral analysis.Based on this,first part of this work has established spectrophotometer and laser induced fluorescence spectrographic methods based on the liquid-core waveguide,and made it successfully apply to detecting iron and the cupric ion concentration.Second part of the work the has carried on in-tube SPME combined with liquid chromatography,the work has been made by installing the self-made capillary extraction column to the liquid chromatography injector as extraction device.Examination sensitivity of three kind organic phosphorus pesticide has been effective enhanced.The whole text is divided into six chapters.The first chapter reviewed on the structure,the type,the transmission principle of optical fiber,the liquid-core waveguide analysis in the research and development through literature;summarized the liquid-core waveguide in the various detecting methods and application status.Especially introduced the fluorescence catalysis dynamic method principle and the application range.In second chapter,a liquid core waveguide spectrophotometric with Teflon AF 2400 tubing and a water core was constructed to analysis iron in water.The geometry of excitation light and the influence of tube length and diameter was researched.The results indicated that the optimal flow rate of pump was 1.2 ml/min.The molar absorbance coefficient was 1.39×10⁵L.mol^-1.cm^-1and was improved in one order of magnitude compared with conventional spectrophotometry.In the range of 0～0.8μg/ml,LCW method showed good linearity and good recovery over the range of 104%～108%,and the limit of detection was 0.892ng/ml. Chapterâ…¢has established a kind laser induced fluorescence spectrographic methods based on the liquid-core waveguide.The detecting condition of method was optimized, including reduces the disturbance of source and increases the exciting light intensity through the adjustment position of laser illuminating;The detection signal to noise ratio was increased when optimizes the integration time and the smoothing width of CCD detector.When appied to detect the Cu²⁺that catalyse the oxidation of rhodanin B by hydrogen peroxide,the observed detection limit is 0.022μg/L in the continuous-flow mode.The high sensitivity of the detector is suggested to partly be due to the efficient rejection of scattered laser light in the LCW by imaging detection of CCD.Chapterâ…£reviewed on the SPME principle through literature summary,the type and preparation of Extraction coating;the operation mode of manual SPME conjunction with liquid chromatography was introduced;three mainstructures way of in-tube SPME-HPLC system were introduced and evaluated.Summarized several kind of coating used in-tubes solid phase microextraction and and Application Status of in-tube SPME-HPLC system.Chapterâ…¤bonded hydroxy terminated PDMS extracted layer on the capillary inner wall using sol-gel method;discussed the sol-gel reaction conditions,and the response steps and time within the capillary;the micro-structure of Extraction layer was observed by scanning electron microscope pictures;Since the rough surface structure of the extraction layer,organic-inorganic nature of gel layer and the bonding of polymer to the capillary wall;made the extraction layers having a strong capacity extraction and good stabilizability.Chapterâ…¥established in-tube SPME HPLC system through refitting Agilent1100 liquid chromatography automatic injector;the adsorption and desorption of SPME was completely automated.The experiments found the best extraction balance condition and solvents to elution;air stuff was used to eliminate interference from the residual flow phase.The detection showed high efficiency of extraction device, maximum 37.5 times the enrichment factor achieved compared to the direct injection method;The method had a good precision and linear in a certain concentration range thought to be a simple and efficient detection method.