ABSTRACT
Objective:To establish the analysis method for the determination of Ni, Cu and Zn in aluminum food packaging mate-rials by inductively coupled plasma atomic emission spectrometry ( ICP-AES) . Methods: A small amount of EDTA was added to the test solution till the concentration at 0. 010 0 mol·L-1 and the pH value was adjusted to 5. 0. Strong acid cation exchange fibers were used for the assisted extraction of Al3+ with ultrasonic. Al3+ could not quickly form a complex anion with EDTA, so it was adsorbed by the strong acid cation exchange fibers. Cu2+, Ni2+ and Zn2+ could form complex anions with EDTA rapidly, so they could not be ad-sorbed by the strong acid cation exchange fibers and were left in the solution to be determined. Results:After the separation, the con-tents of Cu, Ni and Zn were not lost, and the content of residual aluminum was about 170 times of that of Cu, Ni and Zn, which had not interferece with the determination of Cu, Ni and Zn. The sample standard addition recovery was within the range of 98. 3%-104%with RSD of 0. 2%-2. 5%(n=5). The relative errors between the measured values and the certified values of standard substances were less than 5. 0%. Conclusion:The proposed method can be successfully applied in the separation and determination of Cu, Ni and Zn in aluminum cans, barbecue aluminum foil and standard substances.
ABSTRACT
Objective: To establish the method for quality control of Compound Herba Houttuyniae Granules(Herba Houttuyniae, Radix Scutellariae, Radix Isatidis, Flos Lonicerae, Fructus Forsythiae). Methods: Herba houttuyniae, Flos Lonicerae, Fructus Forsythiae in this medicine were identified by TLC. The content of baicalin in this medicine was determined by HPLC. Results: Herba Houttuyniae, Flos Lonicerae, Fructus Forsythiae could be identified by TLC. The content of baicalin determined by HPLC was 7.33～7.65 mg?g -1 . The average recovery was 99.16% and the RSD was 1.06%( n =6). Conclusion: The method was simple, accurate and with strong specificity and can be used for the quality control of Compound Herba Houttuyniae Granules.
ABSTRACT
OBJECTIVE:To establish a HPLC method for content determination of glycyrrbizic acid in Jianwei tea.MET_HODS:A Inertsil ODS-3 column was used with a mobile phase of methanol-0.2mol/L ammonium acetate solution-glacial acetic acid(67∶33∶1).The detection wavelength was 250nm,and the flow rate was 1.0ml/min.RESULTS:There was a good linear relationship between the sample size and peak area score of glycyrrbizic acid in the range of 0.784?g～4.70?g(r= 0.9 999).The average recovery was 99.1%(RSD=1.26%).CONCLUSION:The present method is convenient,accurate and practicable,and it can be used for quality control of Jianwei tea.