糙米中砷形态检测方法的对比研究

Comparative study on the detection methods of arsenic in rice

中文关键词:  糙米  砷形态  液相色谱法  原子荧光光度计  电感耦合等离子体质谱仪

英文关键词:rice  arsenic species  liquid chromatography  atomic fluorescence spectrometry  inductively coupled plasma mass spectrometer

中文摘要:

      目的 比较液相色谱-原子荧光光谱法(high performance liquid chromatography atomic fluorescence spectrometry, HPLC-AFS)和液相色谱-电感耦合等离子体质谱法(high performance liquid chromatography inductively coupled plasma mass spectrometry, HPLC-ICP-MS)两种方法对糙米中砷形态的测定。方法 糙米样品经0.15 mol/L硝酸溶液提取, 分别采用HPLC-AFS联用仪, 流动相为15 mmol/L的磷酸二氢氨缓冲溶液(pH=6.0), 经CNWSep AX阴离子交换色谱柱分离检测; 同时, 采用HPLC-ICP-MS联用仪, 流动相为含5 mmol/L己烷磺酸钠、20 mmol/L柠檬酸的缓冲溶液(pH=4.3), 经安捷伦Zorbax SB-Aq反相色谱柱分离检测。结果 两种方法检测4种砷形态在5.0~ 100.0 ng/mL范围内线性良好, 相关系数均在0.999以上; HPLC-AFS法的检出限分别为2.3、0.6、1.0和1.1 ng/mL, 加标回收率在85.1%~106%之间, 相对标准偏差(relative standard deviation, RSD)均小于5%; HPLC-ICP-MS法的检出限分别为0.1、0.1、0.1和0.2 ng/mL, 加标回收率在82.8%~106%之间, 相对标准偏差(RSD)均小于5%。结论 两种方法都可以满足糙米中4种砷形态的检测, 在实际情况中可根据需要选择相应的检测方法。

英文摘要:

      Objective To compare the determination of arsenic species in brown rice by high performance liquid chromatography atomic fluorescence spectrometry (HPLC-AFS) and high performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Methods Rice samples were extracted with 0.15 mol/L nitric acid solution and separated by HPLC-AFS with 15 mmol/L ammonia dihydrogen phosphate buffer solution (pH=6.0) as mobile phase, and determined by CNWSep AX anion exchange chromatography column. Meanwhile, the samples were separated by HPLC-ICP-MS with 5 mmol/L sodium hexane sulfonate and 20 mmol/L citric acid buffer solution (pH=4.3) as mobile phase, and determined by Agilent Zorbax SB-Aq reversed phase chromatography column. Results The linearity of the 2 methods was good in the range of 5.0?100.0 ng/mL, and the correlation coefficient was above 0.999. The detection limits of HPLC-AFS were 2.3, 0.6, 1.0 and 1.1 ng/mL, respectively, the recoveries were between 85.1% and 106%, and the relative standard deviation (RSD) was less than 5%. The detection limits of HPLC-ICP-MS were 0.1, 0.1, 0.1 and 0.2 ng/mL, respectively. The recoveries were between 82.8% and 106%, and the relative standard deviation (RSD) was less than 5%. Conclusion Both methods can satisfy the detection of 4 arsenic forms in rice, and the corresponding detection method can be selected according to needs in actual situations.