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A comparison study of the adsorption capacity of octadecyl- and triacontylbonded phases was conducted. The latter exhibited greater capacity for phthalates dissolved in water than the former. A new device containing triacontyl packing was developed lo couple solid phase extraction (SPH) to narrow-bore column high performance liquid chromatography (HPLC) with ultraviolet absorption detection. The device consisted of a syringe filter unit packed with triacontyl-bonded silica, a gas-tight syringe (no needle), and an HPLC injection syringe needle. After a sample solution filled in a 5mL syringe was delivered to the device by use of a syringe pump, the .syringe was replaced with a 250 μL syringe filled with an eluting solvent. By inserting the needle of the device into the needle port of an injection valve followed by forcing the solvent through the packed bed, the analyte was desorbed from the bed and introduced into the sample loop of the valve. On rotating the valve, the extract was introduced into an HPLC column and separation was stalled. The performance of the device was evaluated by using diheptyl phthalate (DHP) and di-2 ethylhexyl phthalate (DEHP), spiked in water as samples. Preconcentration factors of 58 and 51 were attained with the device for DEP and DEHP, respectively. The method was linear in the range 1.0-50&ng/mL. Limits of detection (LOD)s were found to be 0.8 and 0.9 ng/mL for DHP and DEHP, Respectively. [ABSTRACT FROM AUTHOR]

Two-type polymeric chiral stationary phases (pCSPs) were prepared by surface grafting of chiral acryl-type monomers on a silica gel surface modified with 3-(trimethoxysilyl)propylmethacrylate. The prepared pCSPs were characterized by IR, FT-Raman, scanning electron microscopy, and elemental analysis. In addition, two-type monomeric chiral stationary phases (mCSPs) were also prepared. The racemic analytes were separated using the prepared mCSPs and pCSPs. The separation factor (α) and capacity factor (k1) of the racemic analytes for the pCSP and mCSP were compared. The α and k1 values of the mCSP were higher than those of the pCSP. [Copyright &y& Elsevier]