| Self-assembly is one of the important research topics in biomimetic and supramolecular phemistry. It has been found a wide application in life, material, and environmental science. When a drop of diluted solution spilled on a solid surface, a self-ordered ring (SOR) of solutes could be formed as long as (1) the solvent meets the surface at a non-zero contact angle, (2) the contact line is pinned to its initial position, and (3) the solvent evaporates.In this dissertation, we first studied the peculiarities of the SOR of a,b,y,5-tetrakis[4-(trimethylammoniumyl)phenyl]porphine (TAPP)-DNA and acridine orange (AO)-DNA. We find that a fluorescent SOR of TAPP can be formed on a dimethyl dichlorosilane (DMCS) modified glass slide, and the fluorescence emission of the SOR can be greatly enhanced by DNA when the pH of the solution is 7.54. Linear responses are obtained between the maximum enhanced fluorescence intensity (7max) and calf thymus DNA (ctDNA) in the range of 0.10-3.00 picomole, and fish sperm DNA (fsDNA) in the range of 0.20-3.00 picomole. Limits of determination are 6.76 femtomole for ctDNA and 19.1 femtomole for fsDNA, respectively.Also, at pH 5.62, acridine orange (AO) can form a SOR with the help of poly vinyl alcohol-124 (PVA-124), and its fluorescence intensity can be selectively enhanced by calf thymus DNA (ctDNA). Two times offish sperm DNA or yeast RNA, or proteins will not interfere the determination. When a drop of 0.2uL was spotted, linear response can be observed in the range of 120-720 f mol ctDNA, and the limit of determination (3cr) is 4.4 fmol. The method was developed for the selective determination of ct DNA in synthetic samles.The results of the above two systems show that when the volume of the droplet is less than 3.0ul, the radius of the SOR is proportional to the cube root of its volume, and the coefficient is dependent on the characteristic of the substrate. As to the SOR of fluorophores, the maximum fluorescence intensity (Imax) is proportional to the molar quantities of fluorophores in the droplet if the distribution of fluorophores across ring diameter direction can be described as Gaussian function. The coefficient here is decided by volume of the droplet, radius of the SOR, and the width of the ring section. So a quantitative basis for the SOR method has been established. This paper also gives a comparison of sensitivities between SOR and Spot method. The theoretic discussion shows that SOR method is more sensitive than Spot analysis for the solutes can accumulate along the ring. Hence the SOR method may have a wide application in bio-chemical and environmental analysis.Subsquently, we discussed the possibility of the application of SOR technique in environmental analytical chemistry. Four systems, including TAPP-Cu, a,b,y-tetrakis (4-sulfonylphenyl) porphine (TPPS4)-Cd, acid chrome dark blue (AB)-Al, and calcein red (CR)-Al have been examined. ,Firstly, a SOR method for the quantitative determination of trace amount of Cadmium (II) and Copper (II) in water and serum samples by the using of porphyrin TPPS4 and TAPP respectively. When the pH is 9.10 and the volume of the droplet is O.lOul, 1.0x10-14-2.0x10-13 mol of Cd (II) can be determined, and the limit of determination was 5 fmol (3 d) per ring. Water samples were determined with the RSD of 3.2-3.8%. When the pH is 5.0, the fluorescence intensity of the SOR of TAPP can be quantitatively quenched by trace amount of copper (II), the linear range is 0.01-0.16 pmol per ring and the limit of determination is 2.22 fmol (volume of the droplet, 0.20ul). Four samples of serum have been determined satisfactorily.Secondly, two SOR methods for the determination of aluminum in water samples (AB-A13+) and serum samples (CR-A13+) were presented. As to CR, when the pH is 4.0, the binding was incubated at water bath for 15 min, and the volume of the droplet is 0.20ul, linear response was observed in 0.02-0.4 pmol, and the limit of determination is 2.57 fmol. To AB, when the pH is 5.2, the binding reaction wasincubated a...
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