Alegría A, Barberá R, Farré R, Ferrer E, Lagarda M J, Torres M A
University of Valencia, Faculty of Pharmacy, Nutrition and Food Chemistry, Spain.
J AOAC Int. 1998 Mar-Apr;81(2):457-61.
A flow injection hydride atomic absorption spectrometric (FI-HAAS) method was developed for determining selenium in human milk and whole blood after microwave digestion of the sample. The sample (2 mL human milk or 0.25 mL blood) was introduced into the microwave vessel with 1.5 mL HNO3 and 0.25 mL H2O2 and 300 W (4 min) and 600 W (4 min) were applied. The digestion was completed by heating to 140 degrees C (2-3 h). Se (VI) was reduced to Se (IV) with hydrochloric acid. The instrumental conditions for FI-HAAS (concentrations of reducing agent and carrier acid, flow rate of argon carrier gas, and sample volume injected) were optimized. The detection limit of the proposed method was 0.23 ng/mL (assay) or 115 pg Se (absolute) in biological samples (1.15 ng/mL milk, 10.4 ng/mL blood). The precision values were 5.0% for milk and 4.0% for blood. The accuracy was evaluated with 2 reference materials, National Institute of Standards and Technology Non-Fat Milk Powder (found: 104.3 +/- 7.2 ng/g, certified: 110 +/- 10 ng/g) and Whole Blood Seronorm (found: 81 +/- 7.3 ng/mL, reference: 83 +/- 4 ng/mL). The results show the suitability of the method for selenium determination in human milk and whole blood. The method was applied to whole blood samples obtained from pregnant women and to human milk.
建立了一种流动注射氢化物原子吸收光谱法（FI-HAAS），用于测定经微波消解后的人乳和全血中的硒。将样品（2 mL人乳或0.25 mL血液）加入到含有1.5 mL硝酸和0.25 mL过氧化氢的微波消解罐中，施加300 W（4分钟）和600 W（4分钟）的功率。通过加热至140℃（2 - 3小时）完成消解。用盐酸将硒（VI）还原为硒（IV）。对FI-HAAS的仪器条件（还原剂和载流酸的浓度、氩气载气的流速以及进样体积）进行了优化。该方法在生物样品（1.15 ng/mL牛奶，10.4 ng/mL血液）中的检测限为0.23 ng/mL（测定值）或115 pg硒（绝对量）。牛奶的精密度值为5.0%，血液的精密度值为4.0%。使用两种标准物质，美国国家标准与技术研究院脱脂奶粉（测定值：104.3±7.2 ng/g，认证值：110±10 ng/g）和全血血清标准物质（测定值：81±7.3 ng/mL，参考值：83±4 ng/mL）评估了准确性。结果表明该方法适用于人乳和全血中硒的测定。该方法应用于从孕妇采集的全血样品和人乳。
