A new method for the determination of organic acids in tobacco was established based on matrix solid phase dispersion was established. The samples and graphitized carbon black sorbent (1:4) were homogenized in a mortar for 5 min and then packed into a cartridge. The organic acids were eluted from the cartridge with water. Then, they were analysed by high performance liquid chromatography with 2% methanol (containing 0.01 mol/L NaH2PO4 buffer, pH 2.98) as mobile phase at the flow rate of 2.0 mL/min and detected at wavelength of 210 nm. The six organic acids were separated on a ZORBAX Stable Bound (4.6×50 mm, 1.8 m m) column within 3 min. The limits of detections (S/N=3) were below 200 m g/L. The mean recoveries are range from 94% -98%, and the relative standard deviations are below 3.0%. This method had been successfully applied to the determination of organic acids in tobacco with good results.
Zhang Xin, Na Ji, Shi Yundong, Zhu Huixian, Hu Qiufen, Dong Xuecheng
(1 Department of Chemistry, Yuxi Teacher's College, Yuxi 653100; 2 Department of Chemistry, Yunnan Institute of the Nationalities, Kunming 650031, China)