Journal of Saudi Chemical Society (2012) 16, 31–33 King Saud University Journal of Saudi Chemical Society www.ksu.edu.sa www.sciencedirect.com ORIGINAL ARTICLE Determining mineral elements in four kinds of grains from Beijing market by ICP-MS simultaneously Zhang Hongxing a, Rui Yu-Kui a b b,* Department of Food Science, Beijing Agricultural College, Beijing 102206, China College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China Received 24 August 2010; accepted 17 October 2010 Available online 28 October 2010 KEYWORDS Grain; ICP-MS (inductively coupled plasma mass spectrometry); Mineral elements; Minor grains Abstract Mineral elements are essential components for human health from food, but their contents in wheat, millet, corn and soybean have not been compared Contents of mineral elements in wheat, millet, corn and soybean from Beijing market of China were detected by ICP-MS The RSDs (relative standard deviation) range from 0.85% to 3.52% and the detecting limits range from 0.13 to 0.85 lg/L, which showed that this method is accurate and precise to detect mineral elements in grains simultaneously The data showed that (1) ICP-MS is a simple and precise method to determine many mineral elements in grains simultaneously (2) Elements followed by descending order in four grains are usually K > Mg > Ca > Fe > Zn > Mn > Cu > Mo > Li, and grains arranged in order from high to low levels of mineral elements are usually soybean > millet > wheat corn So we should take in more minor grains, such as soybean and millet on daily diet ª 2010 King Saud University Production and hosting by Elsevier B.V All rights reserved Introduction Mineral elements are essential for life growth and development and they are mostly bound to proteins, forming metal* Corresponding author Address: Yuanmingyuan Xilu No 2, Haidian District, Beijing 100193, China Tel.: +86 10 62732574 E-mail address: ruiyukui@163.com (Y.-K Rui) 1319-6103 ª 2010 King Saud University Production and hosting by Elsevier B.V All rights reserved Peer review under responsibility of King Saud University doi:10.1016/j.jscs.2010.10.014 Production and hosting by Elsevier loproteins, especially enzymes Usually mineral elements accomplish decisive functions to maintain human health, and their deficiency can lead to undesirable pathological conditions that can be prevented or reversed by adequate supplementation (Cesar, 2005) Most of mineral elements in human body come from daily food, especially grains (Gai et al., 2004) Wheat, millet, corn and soybean are four kinds of essential grains in northern China, so determining and comparing contents of mineral elements in these grains are very meaning for human health ICP-MS (inductively coupled plasma mass spectrometry) is a new method to determine many elements simultaneously and has high accuracy (Rui et al., 2009a, 2007, 2009b, 2008) So we compared contents of ten mineral elements in wheat, millet, corn and soybean grains 32 Table H Zhang, Y.-K Rui Microwave digestion temperature control program Step Maximum power (W) Climb time (min) Pressure (psi) Temperature (°C) Hold time (min) 1200 1200 10 300 300 120 190 10 Table 2.2 Experimental method Operating parameters for ICP-MS Method parameters Value Power (W) Plasma flow (L/min) Nebulizer flow (L/min) Auxiliary flow (L/min) Sampling depth (mm) Scanning times Pump rate (rpm) Rinse time (s) Replicates Replicate read time (s) Instrument stabilization (s) Sample delay uptake (s) 1200 14.0 0.98 1.20 2.0 200 20 10 10 10 60 Table Relative standard deviations and detecting limits Elements Detecting limits (lg/L) RSD (%) Li Ca Mg Fe Mn Cu Zn Mo K Se 0.72 0.61 0.85 0.13 0.25 0.37 0.32 0.64 0.77 0.59 3.52 3.14 2.79 1.20 0.85 1.08 1.31 3.19 2.78 2.61 Table Contents of 10 mineral elements in four kinds of grains from Beijing (lg/g) Mineral elements Corn Soybean Wheat Millet Li Ca Mg Fe Mn Cu Zn Mo K Se 0.014 47.69 313.09 16.99 1.42 0.647 6.11 0.248 1688.87 Null 0.065 699.53 1184.51 108.44 15.11 6.698 31.70 2.403 9611.04 0.352 0.020 200.63 321.11 19.02 6.69 2.896 8.01 0.175 1569.34 0.067 0.012 154.20 1129.71 34.13 11.16 6.119 26.89 0.261 2285.54 Null The samples were prepared by microwave digestion; the microwave digestion conditions are shown in Table After cooling the digestion tank, adding volume to 25 mL for detection Detailed methods for these were given by Shen et al (2009) and Oăzkan et al (2010) And the operating parameters for ICP-MS are shown in Table Results and analysis The relative standard deviations of ten detected elements (Li, Ca, Mg, Fe, Mn, Cu, Zn, Mo, K and Se) range from 0.85% to 3.52% and the detecting limits range from 0.13 to 0.85 lg/ L All these data showed that this method can determine these 10 mineral elements simultaneously, and this method is accurate and precise (Table 3) All these four kinds of grains from Beijing market were found with Li, Ca, Mg, Fe, Mn, Cu, Zn, Mo and K, but Se was not found in corn and millet In the four kinds of grains, the list from high to low is K > Mg > Ca > Fe > Zn > Mn > Cu > Mo > Li, and the list of the four grains is soybean > millet > wheat corn (Table 4) Conclusions (1) ICP-MS is simple and precise method to determine many mineral elements in grains simultaneously (2) Elements followed by descending order in four grains are usually K > Mg > Ca > Fe > Zn > Mn > Cu > Mo > Li, and grains arranged in order from high to low levels of mineral elements are usually soybean > millet > wheat corn So we should take in more minor grains, such as soybean and millet on daily diet Acknowledgements The authors appreciate the financial support of the Programs of Beijing Emphasis Construction Subjects (No PXM2009_ 014207_078172) We thank Ms Ouyang Li (School of Public Health, Peiking University, China) for detecting References Materials and methods 2.1 Materials and instruments Wheat, millet, corn and soybean were brought from supermarket of Beijing The ICP-MS instrument was the PQ Excell instrument (ELAN DRCII, PE Company, USA) Cesar, G.F., 2005 Relevance, essentiality and toxicity of trace elements in human health Mol Aspects Med 26, 235–244 Gai, K., Dong, Y.J., Fu, F., 2004 Brief introduction about the microelement in foodstuff J Longdong Univ (Nat Sci Ed.) 14 (1), 4648 Oăzkan, Oă., Safak, U., Nuray, E., 2010 Study on the behavior of the trace metal and macro minerals in Mytilus galloprovincialis as a Determining mineral elements in four kinds of grains from Beijing market by ICP-MS simultaneously bioindicator species: the case of Marmara Sea, Turkey J Verbr Lebensm doi:10.1007/s00003-009-0544-8 Rui, Y.K., Yu, Q.Q., Jin, Y.H., Guo, J., Luo, Y.B., 2007 Application of ICP-MS to the detection of forty elements in wine Spectrosc Spect Anal 27 (5), 1015–1017 Rui, Y.K., Shen, L., Sheng, J.P., 2008 Content of trace elements and heavy metals in Chinese winter jujube fruit Spectrosc Spect Anal 28 (8), 1928–1930 33 Rui, Y.K., Qu, G.Q., Zhang, F.S., 2009a Distribution of six trace elements in Fuji apple Spectrosc Spect Anal 29 (2), 509–510 Rui, Y.K., Wang, W.Y., Liu, P.H., Zhang, F.S., 2009b Mineral element distribution in organs of dual-toxin transgenic (Bt + CpTI) cotton seedling Plant Biosyst 143 (1), 137–139 Shen, X.Y., Xie, C.X., Deng, W.P., Qian, X.Y., 2009 ICP-AES determination of trace elements in violet grown in Tianshan Phys Test Chem Anal (Part B: Chem Anal.) 45 (12), 1428 ... macro minerals in Mytilus galloprovincialis as a Determining mineral elements in four kinds of grains from Beijing market by ICP- MS simultaneously bioindicator species: the case of Marmara Sea,... All these four kinds of grains from Beijing market were found with Li, Ca, Mg, Fe, Mn, Cu, Zn, Mo and K, but Se was not found in corn and millet In the four kinds of grains, the list from high... 3.14 2.79 1.20 0.85 1.08 1.31 3.19 2.78 2.61 Table Contents of 10 mineral elements in four kinds of grains from Beijing (lg/g) Mineral elements Corn Soybean Wheat Millet Li Ca Mg Fe Mn Cu Zn Mo