Wuilloud Rodolfo G, Kannamkumarath Sasi S, Caruso Joseph A
Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, USA.
Anal Bioanal Chem. 2004 Jun;379(3):495-503. doi: 10.1007/s00216-004-2592-3. Epub 2004 Mar 27.
Molecular size distribution patterns of Cu, Mn, Ni, and Zn were determined in several nut species by size-exclusion liquid chromatography (SEC) coupled on-line to UV and inductively coupled plasma mass spectrometry (ICP-MS) for detection. The molecular weight (MW) fractionation of the different metals was performed with a Superdex Peptide column, injecting 100 microL of the extracted solutions. The association of the elements with different MW fractions was observed with sequential detection by UV and ICP-MS. Various separation conditions were evaluated to obtain proper resolution and reproducible results with the size-exclusion column. Complete MW information of the elemental fractions in the nut samples was obtained within a retention time of 30 min. Fractionation of the above mentioned elements was done in nine different nut species commonly found in commercial markets. Variability of the fractionation patterns for two different extraction media, 0.05 mol L(-1) NaOH and 0.05 mol L(-1) HCl, was evaluated for every nut sample. Differences in the elemental fractionation patterns were found depending on the extraction procedure, nut species, and the type of element studied. It was also observed that the elements studied showed predominant association with high MW fractions when extracted with basic solution whereas with acidic extraction media only low MW fractions were obtained.
通过在线连接紫外和电感耦合等离子体质谱（ICP-MS）检测的尺寸排阻液相色谱（SEC），测定了几种坚果中铜、锰、镍和锌的分子大小分布模式。使用Superdex Peptide柱对不同金属进行分子量（MW）分级，注入100微升提取液。通过紫外和ICP-MS顺序检测观察元素与不同MW级分的关联。评估了各种分离条件，以通过尺寸排阻柱获得适当的分辨率和可重复的结果。在30分钟的保留时间内获得了坚果样品中元素级分的完整MW信息。对商业市场上常见的九种不同坚果进行了上述元素的分级。对每个坚果样品评估了两种不同提取介质（0.05 mol L(-1) NaOH和0.05 mol L(-1) HCl）的分级模式的变异性。发现元素分级模式因提取程序、坚果种类和所研究元素的类型而异。还观察到，用碱性溶液提取时，所研究的元素主要与高分子量级分相关联，而用酸性提取介质时，仅获得低分子量级分。
