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A new main-chain type ionic homopolymer GC stationary phase which has high separation efficiencies for alcohols, phthalates and PAHs and a maximum programmable temperature of 400 C was prepared and studied.Ionic liquids (ILs) are salts with relatively low melting points; they are usually liquid around ambient temperature. ILs have recently attracted a lot of interest due to their unique properties. Their minuscule vapor pressure and inflammability make them ''green'' solvents, in contrast to conventional organic solvents. Moreover, other properties such as solubility, conductivity, and thermal stability can be tuned by changing the substituted functional groups or the combination of cations and anions. These properties make ionic liquids multi-functional and designable. Detailed descriptions of these properties can be found in Ref. 1-7.Recently, Armstrong et al. demonstrated a series of ionic liquids as the stationary phases for gas chromatography. The ionic liquids have many properties that match the requirements of GC stationary phase, including high solubility, thermal stability, chemical stability, viscosity, wettability, and most important of all, the designability. Many successful applications and detailed discussions are available in the literature. [8][9][10] However, in spite ionic liquids normally having high thermal stability, they are still not comparable to some of the conventionally thermal-stable stationary phases. It could be due to the ion evaporation or decomposition under high temperature. Polymerized ionic liquids or ionic liquid polymers (PILs) show great promise. Ions are tethered to the backbone of the polymer. Despite the loss of ion mobility, the mechanical strength of the whole substrate increases as the does thermal stability. 11,12 The comb-like imidazolium based ionic liquid polymers show a decomposition temperature ranging from 280-380 C. More recently, Armstrong et al. demonstrated a series of

A method for the determination of four dialkylphosphate metabolites in urine by strong anion exchange disk (SAX) was investigated. Calcium hydroxide was added to a 1-mL urine sample to reduce interference. The aliquot was passed through the SAX disk to accumulate dialkylphosphate metabolites on the disk. The retained dialkylphosphate metabolites were derivatized with methyl iodide in acetonitrile online, and the resulting methyl esters of dialkylphosphate metabolites were directly analyzed by capillary column gas chromatography with flame photometric detection. The recoveries of these dialkylphosphate metabolites were found to be stable. When the intact sample was diluted with deionized water at a 1:1 ratio, the recoveries were both increased and stabilized. The urine samples collected from eight fruit farmers showed that levels of dialkylphosphate metabolites in urine were significantly different before and after pesticide application, indicating the method established in this study is applicable for real sample analysis. Compared with previous studies, this method not only can greatly simplify sample preparation, but it can also significantly reduce the consumption of toxic solvents in sample preparation.