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With the rapid development of the life sciences, bio-engineering, and environmental science disciplines, the subject of increasingly complex and diverse, the separation and detection of the complex matrix of trace and ultra-trace components become a prominent problem. While the modern instrument detection limit of the analytical method is getting low, but to direct analysis of the content of these components is also often encounter difficulties, and sometimes even impossible, this is because the one hand, the sample itself, the physical and chemical state not suitable for the direct determination or analysis methods component of very low levels of sensitivity is not enough: the other hand, there is a matrix interference, or lack of appropriate calibration standards and reagents. Therefore have to rely on a variety of separation and enrichment technologies to improve the sensitivity and selectivity of the analytical method. Although atomic spectroscopy with high sensitivity, but analysis often required prior to the determination of the analyte content is extremely low or too complex sample chemical composition supplemented by chemical separation / preconcentration means of purification and enrichment of analytes and removing the interference matrix. Separation and enrichment technologies associated with not only measured element concentration can improve, and to some extent eliminate matrix interference, and effectively improve the analytical detection limits, precision and accuracy. Solid phase extraction enrichment technology and atomic spectra associated with has been widely used in the separation and enrichment of trace elements and morphological analysis, adsorption material which is an important factor to affect the analytical sensitivity and selectivity, and looking for new, performance The superior adsorption material is a hot topic in the technology research. Nanomaterials in recent years by the widespread attention as a new functional materials, has a new series of different physical and chemical properties. Its large specific surface area, around the surface atoms to neighboring atoms is missing, having unsaturation stabilized, easy to combine with other atoms, and having large chemical activity, and therefore the metal ion has a strong adsorption capacity and larger the adsorption capacity of adsorbent material is an ideal. Nanoparticles as an adsorbent material for the separation of trace element enrichment can improve the sensitivity of the analytical method, the lower limit of detection, an important application value. Nano titanium dioxide materials for the study of metal ion separation and enrichment has been reported, but due to the dispersion of nano-TiO 2 volatile activity, easy reunion, difficult to recycle and other shortcomings, severely limiting its practical application. Supported Nano TiO 2 by chemical vapor deposition, TiO 2 powder fixed sol - gel method nano TiO 2 immobilized on a solid carrier surface, greatly enhancing the the nano TiO 2 stability and reproducibility. Supported Nano TiO 2 has been widely applied in the photocatalytic degradation of pollutants, but as an adsorbent material for the separation and enrichment of metal ions is reported rarely. The purpose of this paper is the use of the sol - gel method nano titanium dioxide load to the surface of the silica gel, systematic study supported nano titanium dioxide material adsorption properties of inorganic elements and different valence states, on this basis, Trace Amounts separation and enrichment of elements and morphological analysis. The main contents are summarized as follows: (1) Preparation of supported nano titanium dioxide adsorption properties of Au and Pb, optimized for a variety of factors that affect the adsorption and liberation FAAS and GFAAS detection means, to establish a Determination of a new method of Au and Pb. The method has been successfully applied to the analysis of real samples. (2) to GFAAS as a means of detection, research supported nano titanium dioxide adsorption of As (Ⅲ) and As (Ⅴ) performance to achieve selective separation of the two selected pH conditions affecting adsorption optimize various factors and liberation, the establishment of a new method of an arsenic speciation analysis.
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