摘要
建立一种简便、快速、准确的食品中硒的测定方法;检测新资源食品芝麻叶、野生四叶参、野生菜葛根、野生葛花及桑蚕蛹中的硒含量。用1mg·mL-1硝酸镍为基体改进剂,加入体积分数为0.1%TritonX-100和0.5%硝酸(1∶1),以改善样液的表面张力。用HITACHIZ-5000型石墨炉原子吸收光谱仪及全自动进样方法进行硒含量测定。石墨炉采用光控升温方式,硒的灰化温度按程序升温方式进行,程序升温分为干燥、灰化、原子化和净化。该方法的测定限为18.6μg/L,精密度为3.26%￣9.29%(RSD),加标回收率为92.1%￣108.8%。该方法具有测定简便、快速和准确等特点,可作为食品中硒含量测定的良好方法。
A method has been developed for the direct determination of Se in Pueraria lobata （Willd） Ohwi by graphite furnace atomicabsorption spectrometry. Matrix modifiers of nickel Nitrate and 0.10% Triton X-100 has been added to testing samples. For 20 μL aqueous analytical solutions delivered into the graphite tube, analytical curves in the 40.0 μg ·L^-1 with good hnear correlation were established. Pyrolysis and atomization temperatures were evaluated using pyrolysis and atomization curves, respectively. The optimized heating program （temperature, ramp time, hold time） of the graphite tube of the HITACHI Z-5000 atomic absorption spectrometer was： dry steps （800 C, 5 s, 10 s; 1 000 C, 5 s, 10 s; 1 400 C, 30 s, 20 s） ; air-assisted pyrolysis step （8 000 C, 20 s, 10 s） ; pyrolysis step （12 000 C, 20 s, 10 s） ; atomization step （25 000 C, 0 s, 5 s） ; clean step （27 000 C, 0 s, 4 s） . The method was applied for Se determination in Pueraria lobata （Willd） Ohwi samples ar,d results were in agreement at 95% confidence level. The limit of detection is 1.86 μg/L, relative standard deviation （RS1）： is 3.26%-9.29%%. Recovery rate of selenium was 92.1%-108.8%, concurrent interfere is low. This method of determining selenium in Puerana lobata （Willd） Ohwi is the best.
出处
《农产品加工（下）》
2006年第7期68-69,73,共3页
Farm Products Processing
关键词
原子吸收光谱法
石墨炉
新资源食品
硒
atomic absorption spectrometry
graphite furnace
new rescourse tood
selenium
