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The nanoparticles of polylactide (PLA) and poly(lactide-co-glycolide) (PLGA) were prepared by the binary organic solvent diffusion method. The yield, particle size and size distribution of these nanoparticles were evaluated. The yield of nanoparticles prepared by this method is over 90%, and the average size of the nanoparticles is between 130–180 nm. In order to clarify the effect of the organic solvent used in the system on nanoparticle yield and size, the cloud points of PLA and PLGA were examined by cloud point titration. The results indicate that the yields of nanoparticles increase with the increase of ethanol in the acetone solution and attain the maximum at the cloud point of ethanol, while the size of nanoparticles decreases with the increase of ethanol in the acetone solution and attains the minimum at the cloud point of ethanol. The optimal composition ratio of binary organic solvents coincides to that near the cloud point and the optimal condition of binary organic solvents can be predicted.

Distribution behavior of terbutaline enantiomers was examined in the aqueous and organic solvent of a two-phase system containing L-dibenzoyltartaric acid and lipophilic phase transfer reagent of Na-tetraphenylborate. The influences of pH, organic solvents, concentrations of Na-tetraphenylborate and L-dibenzoyltartaric acid on the partition coefficients and enantioselectivity of terbutaline enantiomers, were investigated. The results show that tetraphenylborate lipophilic anion and terbutaline enantiomers form two lipophilic salt complexes, which facilitates the solubility of the enantiomers in the organic phase. L-dibenzoyltartaric acid forms more stable complexes with enantiomer II than with enantiomer I. Enantioselectivity and partition coefficient increase with the addition of the length of alkyl chain of alcohols. pH and concentrations of lipophilic anion and L-dibenzoyltartaric acid influence them obviously and differently.

Two new chiral stationary phases, 2,3-di-O-acetyl-6-O-trimethylsilyl-β-cyclodextrin (DATBCD) and 2, 6-di-O-trimethylsilyl-3-O-acetyl-β-cyclodextrin (DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β-cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β-cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 4143 and 3928, the column efficiencies are respectively 3084 and 4198, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer (k 1) and separation factor(α)of α-phenylethanol on DATBCD stationary phase are respectively 8.23 and 1.019.