聶西度,符 靚
(1.湖南工學院材料與化學工程系,湖南衡陽 421002;2.長江師范學院化學化工學院,重慶涪陵 408100)
ICP-OES法測定堅果中微量元素的研究
聶西度1,符 靚2,*
(1.湖南工學院材料與化學工程系,湖南衡陽 421002;2.長江師范學院化學化工學院,重慶涪陵 408100)
采用微波輔助消解樣品,建立了軸向觀測電感耦合等離子體發射光譜(ICP-OES)法同時測定堅果中B、Na、Mg、Al、Si、S、K、Ca、Mn、Fe、Ni、Cu、Zn、Sr、Mo、Ba等16種微量元素的分析方法。 樣品采用硝酸+雙氧水混合酸微波輔助消解,優化了儀器的最佳測定條件,確定了各待測元素合適的分析譜線。采用國家一級標準物質(芹菜,GBW10048)進行方法驗證,測定結果與標準物質所提供的參考值一致,所有待測元素的檢出限為0.31~18.38μg/L,方法具有良好的精密度和準確度。
電感耦合等離子體發射光譜,微波輔助消解,堅果,微量元素
Abstract:A simple and reliable analytical procedure for the determination of 16 selected elements,namely B,Na,Mg,Al,Si,S,K,Ca,Mn,Fe,Ni,Cu,Zn,Sr,Mo and Ba in nuts by axially viewed inductively coupled plasma optical emission spectrometry(ICP-OES) after microwave digestion of samples was validated in this work.HNO3+H2O2were used to achieve the complete decomposition of the organic matrix in a closed-vessel microwave oven.The working parameters of the instrument were optimized.Appropriate analysis line of various elements was selected.The accuracy of the entire proposed method was confirmed by standard reference material analysis(celery,GBW10048).The results showed a good agreement between measured and certified values for all analytes.The method was shown to be very sensitive with limits of quantification in the range of 0.31~18.38μg/L for all investigated elements.This method was simple,sensitive and precise and could perform simultaneous multi-elements determination of nuts.
Key words:inductively coupled plasma optical emission spectrometry;microwave assisted digestion;nuts;trace elements
堅果又稱殼果,為植物種子的子葉或胚乳,是植物的精華部分,營養價值很高。堅果含有大量碳水化合物、優質蛋白質、脂肪等,還含有礦物質、維生素、氨基酸、膳食纖維等營養成分。在食物的分類中,堅果被歸類為脂肪類食物,高熱量高脂肪是堅果的特性,富含單、多不飽和脂肪酸,包括亞麻酸、亞油酸等人體的必需脂肪酸,對人體的生長發育、增強體質、預防疾病均有極好的功效,是補腦、益智的佳品。堅果種類繁多,一般分為樹堅果和種子兩類。樹堅果主要包括榛子、腰果、核桃、杏仁、開心果、松子、板栗、白果、夏威夷果等;種子則主要包括葵花子、花生、西瓜子、南瓜子等。堅果中微量元素的測定已有相關文獻報道,研究對象多集中于國產和種子類堅果[1-2],而研究方法則主要采用原子吸收法[3-4],分析速度較慢,不適合批量產品的分析,具有一定的局限性。……