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The enantiomeric separation of some poorly water-soluble organophosphorus pesticides (OPs) has been investigated using nonaqueous solvent and aqueous-organic solvent systems. In this work, sodium cholate (SC) either with SDS or gamma-CD was used to achieve enantiomeric separations of four neutral and poorly water-soluble OPs, i.e., profenofos, prothiofos, sulprofos, and pyraclofos. Electrophoretic medium consisted of a mixture of methanol (MeOH) with ACN (4:1 v/v) or a mixture of MeOH with H(2)O and ACN (5:4:1 v/v/v). On one hand, NACE was applied for enantiomeric separation of pyraclofos using a large amount of chiral and achiral surfactants (SC and SDS). On the other hand, H(2)O was added to act as a solvent additive to increase the solubility of gamma-CD in the organic solvents such as MeOH and ACN, in which the solubility of gamma-CD was very low. The presence of H(2)O was found to be particularly useful for the enantiomeric separation of profenofos, prothiofos, and sulprofos. In this way, the range of application of the neutral CDs in CE has been extended. In addition, SC was used as the only electrolyte. The proposed method has been applied for the analysis of soil samples.

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Enantioseparation of tryptophan enantiomers (Trys), tyrosine enantiomers (Tyrs) and phenylamine enantiomers (Phes) by chiral ligand exchange capillary electrophoresis (CLE- CE) using 1-ethyl-3-methyl imidazole L-lactate ([EMIM] [L-Lac ]) as the chiral ligand was studied. The effects of background electrolytes and central ions, the molar ratio and concentration of the chiral ligand and central ion, running buffer solution pH on the enantioseparation of Trys, Phes and Tyrs were investigated. Good enantioseparation of three pairs of enantiomers were obtained with 40.0 mmol/L [EMIM] [L-Lac] and 20.0 mmol/L cupric chloride (pH 4.5). To validate the good behavior of [EMIM] [L-Lac], L-lactate (L-Lac) was further used as the chiral ligand for the enantioseparation of Trys. The contrast experiment showed that Trys could only be partially enantioseparated by L-Lac. Moreover, the enantioseparation was improved by adding 1-ethyl-3-methyl imidazole acetate (EMIM-Ace) which markedly prolonged the migra- tion time of Trys to more than 30 min. In contrast, the migration time of Trys was obtained in 15 min by [EMIM] [L-Lac]. Finally, the enantioseparation mechanism was further discussed. The experimental results showed that in the EMIM-Ace assisting L-Lac system, EMIM-Ace was only used to suppress the electroosmotic flow and was not involved in the chiral ligand exchange reaction, while in the [EMIM] [L-Lac] system, the chiral ligand taking part in the re- action was mainly unionized [EMIM] [L-Lac] rather than L-Lac formed by ionized L-Lac ions.

The hydrolysis of cinnamaldehyde in aqueous solution catalyzed by amino acids has been investigated. Eight amino acids e.g. glycine, proline etc. have been employed as the small molecular organocatalysts. The effect of reaction time, temperature, buffer concentration on the reaction has been studied. Spectroscopic analysis indicated the reaction product is 3-hydroxy-3-phenylpropanal.