電感耦合等離子體質譜法測定富硒蘋果中硒

周慧敏 趙彤

摘 要：本方法預先將試樣進行干燥處理，然后加入硝酸和過氧化氫在電熱板上進行常壓消解，待消化液蒸發至近干后轉移定容，同時加入內標溶液，通過電感耦合等離子體質譜法進行測定。該方法不需要微波消解，可直接準確測定富硒蘋果中硒的含量，定量限低于國家標準6倍，線性范圍為0.002～0.020 mg/L，相關系數R為0.999，加標回收率為81.6%～91.5%，相對標準偏差為4.4%～9.2%，適用于富硒水果等樣品中硒的準確定量。

關鍵詞：電感耦合等離子體質譜法;富硒蘋果;硒

Determination of Selenium in Selenium Rich Apples by Inductively Coupled Plasma Mass Spectrometry

ZHOU Huimin， ZHAO Tong

（Dalian Center for Certification and Food and Drug Control， Dalian 116630， China）

Abstract： In this method， the sample is dried in advance， then nitric acid and hydrogen peroxide are added for digestion on an electric heating plate under normal pressure. After the digestion solution is evaporated to nearly dry， it is transferred to constant volume. At the same time， the internal standard solution is added， and then the samples were determination by inductively coupled plasma mass spectrometry. This method does not need microwave digestion， and can directly and accurately determine the content of selenium in selenium rich apples. The quantitative limit is 6 times lower than the standard method. The linear range is 0.002～0.020 mg/L， the correlation coefficient R is 0.999， the recovery rate is 81.6%～91.5%， and the relative standard deviation is 4.4%～9.2%. It is suitable for the accurate quantitative determination of selenium in selenium rich fruits and other samples.

Keywords： inductively coupled plasma mass spectrometry; selenium-enriched apples; selenium

硒是人體必須的微量元素，具有清除自由基、抗炎、抗腫瘤的抗脂質氧化、延長壽命和提高機體免疫力等作用[1]。人體硒的生理需求量為40 μg/d，缺硒會引起克山病和大骨節病等，還會使機體處于抗氧化應激態，受精能力和胚胎發育能力都會受到一定程度的損傷[2];人體攝入過多的硒則會形成硒中毒，出現脫發、周圍性神經炎和生長遲緩等癥狀[3]。科學補硒對人體健康極為關鍵，因此建立一種快速、準確的食品中硒的測定方法，對人體健康有著重要的意義。

目前食品中硒元素的檢測方法主要以氫化物原子熒光光譜法、電感耦合等離子體質譜法為主[4]。原子熒光光譜法需用濕法消解，即先將試樣完全消解至無機狀態，然后用6 moL/L鹽酸將試樣中Se6+還原到Se4+，過程需要用到3種以上的酸且用量較大，同時用到的玻璃器皿也會帶來一定的污染，造成空白的本底值難以控制;此外富硒蘋果中硒的含量多在20 ～50 μg/kg，因此該方法難以準確測定出富硒蘋果中微量硒。……