ABSTRACT
Corrado Sarzanini Department of Analytical Chemistry, University of Turin, Turin, Italy
I. INTRODUCTION II. SAMPLE HANDLING
A. Matrix Removal and Analyte Preconcentration B. Derivatization
III. CHROMATOGRAPHIC MODES A. Normal and Reversed-Phase Chromatography B. Ion Chromatography C. Ion-Interaction Chromatography D. Chelation Ion Chromatography
IV. METAL SPECIATION A. Arsenic B. Selenium C. Lead D. Mercury E. Tin F. Chromium REFERENCES
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their major drawbacks. The extraction of compounds from a solution onto a solid phase (SPE) using silica, alumina, celite, charcoal, polymeric, or ion-exchange resins has long been practiced. Silica gels or polymers have been bound with a wide variety of functional groups (e.g., alkyl, phenyl, amino, ciano, diol, alkylsulfonate, and quaternary ammonium groups), and more recently with chelating functional groups (e.g., carboxylic, quinolines, iminodiacetic) to provide a specific interaction with analytes. No attempts are made hereafter to define foams, resins, or sorbents of inorganic or organic nature. It must be mentioned that if silica-based supports are used, the residual silanol sites provide, for the analyte, a second type of binding sites, so it is advisable to use as supporting material in the column either a silica C18 end-capped type or a polymeric-based C18 derivatized support.
