Objective:To establish a GC-MS method for the simultaneous determination of 16 phthalate ester plasticizers in oral liquid preparations, compare the purification effect of liquid preparations by liquid-liquid extraction and solid phase extraction and opti-mize the operating parameters to determine the optimal experimental conditions. Methods:The samples were operated by liquid-liquid extraction and solid phase extraction, respectively. Selective ion monitor ( SIM) was adopt, phthalate esters were identified by the rela-tive abundance of major characteristic ions and the content was determined by an external standard method. Results:When the samples were operated by liquid-liquid extraction, the interference was strong with many impurity peaks. Therefore, the solid phase extraction was adopted for the sample pretreatment. GC-MS was used to detect the residues of 16 phthalate ester plasticizers in oral liquid prepara-tions. The detection limit was 0. 02μg·g-1 ,while the calibration curve showed good linearity within the range of 0. 25-8. 0μg·ml-1 with the correlation coefficient between 0. 990 7 and 0. 999 8. The average recoveries were 76. 0%-95. 4%. The relative standard devi-ations were between 2. 3% and 9. 6%(n=6). Conclusion: Pretreated by solid phase extraction, the residues of 16 phthalate ester plasticizers in oral liquid preparations can be detected by GC-MS with the properties of simple, fast, precise and sensitive, and it is suitable for the determination of phthalate esters in oral liquid preparations.

Objective: To establish an HPLC method for the simultaneous determination of three flavonoids in Tianjihuang gran -ules.Methods:A ZORBAX Eclipse XDB-C18 column was used.The mobile phase was methanol-0.2%phosphoric acid solution (42∶58).The detection wavelength was 350 nm and the flow rate was 1.0 ml· min-1.Results:The linear range of isoquercitrin, quer-citrin and quercetin was 4.572-114.300 μg· ml-1(r=0.999 8), 7.028-175.700 μg· ml-1(r=0.999 8) and 2.195-54.880 μg· ml-1(r=0.999 9), respectively.The average recovery was 98.01%(RSD=1.24%, n=6), 98.14%(RSD=0.98%, n=6) and 97.00%(RSD=1.09%, n=6) , respectively.Conclusion:The method is specific and simple,which can be used for the quality con-trol of Tianjihuang granules.