| Porphyrins are macro-heterocyclic compounds formed by interconnection of?-carbon atoms of four pyrrole subunits through a methine bridge(=CH-).There are a variety of porphyrin compounds,due to the differences in the side chains.Commonly,porphyrins are divided into two classes by solubility,i.e.,lipophilic porphyrins and water-soluble porphyrins.Water-soluble porphyrin has been widely used in the field of chemistry including molecular recognition,analytical chemistry,electrochemical and photochemical reactions.Their applications in bio-medical area have also attracted great attention in last decades.Hematoporphyrin and its derivatives are well water-soluble porphyrins.They have been widely studied and applied as a new type of photochemical diagnostic reagents since 1970s,because of its excellent photochemical and photo-physical properties.In this thesis,the potential of hematoporphyrin and its derivatives as optical probes for the detection of pH or acidity was explored.Phthalocyanines are porphyrin-like compounds containing a similar parent structure,which are physico-chemically stable,facile to be synthesized and easy to be modified in parent structure.They have been widely applied in many high-tech fields.Tetrasulfonyl aluminum phthalocyanine(AlS4Pc),a diamagnetic metal phthalocyanine emitting strong fluorescence at red region,has been attracting more and more attention in analytical sciences,because of its good solubility in water,photo-bleaching resistance,photochemical stability,red-emitting characteristics and high quantum yield.This thesis focused on the applications of ion-paired association complex of AlS4Pc for the determination of acidity and Hg(?).This thesis is divided into five sections as following:In chapter 1,the research progress of porphyrins and phthalocyanines in analytical sciences was reviewed.First,the structures,properties and applications of porphyrin and phthalocyanine,as well as their applications in analytical sciences were introduced.The main point of review focused on the applications of porphyrin and phthalocyanine in the determination of acidity and heavy metal ions.Second,the research progress of determination of acidity was reviewed.The significance and the research progress of acidity measurement were introduced and the application of optical probes in the determination of acidity was emphasized.Finally,the progress of the determination of mercury was reviewed.The significance and the research progress of mercury measurement were introduced and the application of optical probes in the determination of acidity was emphasized.In chapter 2,the purpose of this study is to utilize the double-interval responding characteristics to pH of an optical probe,hematoporphyrin monomethyl ether(HMME),for the establishment of a new method for the determination of pH.It was found that the absorption spectra behavior of HMME showed significant correlation with the pH of the media.Further investigation indicated that HMME could respond to two different range of pH,exhibiting a double-interval response.The study pointed out that the responding characteristics of HMME to pH could be applied to the determination of two different interval of pH by a single probe,which was a new discovery of pH optical probe.In addition,HMME was found to be a ratio responding probe,which could overcome the influence of many non pH factors,to achieve a more accurate determination of pH.HMME,as a new type of pH optical probe,has been applied to the determination of pH of trace,viscous and high acidity span samples,for example,food,biological and environmental water samples with satisfactory results.This study expends the application of porphyrin compounds in analytical sciences.In chapter 3,fluorescent hematoporphyrin compounds(HMME and HPH),showed a double-interval responding characteristics to pH.Based on this founding,a new method for the determination of pH was established.It found that the fluorescence spectra behavior of HMME and HPH showed significant correlation with the pH of the media.Further investigation indicated that HMME and HPH could respond to two different range of pH,exhibiting a double-interval response.The study indicated that HMME and HPH could be applied to the determination of two different interval of pH by a single probe,which was a new discovery of pH fluorescence probe.In addition,HMME and HPH were found to be a ratio responding probe,which had the advantage of overcoming the influence of many non pH factors,to achieve a more accurate determination of pH.HMME and HPH,as the new type of pH fluorescence probe,has been applied to the determination of pH of trace,viscous and high acidity span samples in this thesis with satisfactory results.This study expends the application of fluorescent porphyrin compounds in analytical sciences.In chapter 4,a novel method for highly specific detection of strong acids based on the fluorescence recovery of the ion-paired association complex,tetrasulfonated aluminum phthalocyanine(AlS4Pc)-Alcian blue 8GX,which emits at long wavelength was constructed.Under the optimal conditions,the linear range of the calibration curves were 1.00-80.00 mmol/L(HNO3),1.00-200.00 mmol/L(HCl),1.00-120.00 mmol/L(HBr),0.01-80.00 mmol/L(H2SO4),and 0.20-62.40 mmol/L(H2SO3),respectively.The detection limits were 0.15 mmol/L(HNO3),0.15 mmol/L(HCl),0.14 mmol/L(HBr),0.29 mmol/L(H2SO4)and 0.36 mmol/L(H2SO3),respectively.The present method has been applied to the analysis of artificial samples with satisfactory results.In chapter 5,it was found that the fluorescence of AlS4Pc was dramatically quenched by Alcian blue 8GX because of the formation of non-fluorescent association complex(AlS4Pc-Alcian blue 8GX).However,fluorescence of the complex recovered obviously in the presence of Hg(?)in acidic or near neutral media.Screening experiments on common metal ions revealed that only Hg(?)could significantly restored the fluorescence of the complex,while the presence of other metal ions was weak or not restored fluorescence,indicating the high specificity of the response to Hg(?)of AlS4Pc-Alcian blue 8GX.Based on these foundings,a highly specific and sensitivity method for quantitative analysis of mercury(?)ions was proposed. |
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