Zink E W, Moffitt R A, Matson W R
J Assoc Off Anal Chem. 1983 Nov;66(6):1409-13.
The method presented describes the direct determination of lead in evaporated milk in which the milk ashing step prior to analysis is eliminated. Digital instrument readout units are microgram Pb/mL milk. Total analysis time after instrument calibration is less than 3 min per sample. Range of the method is 0.05-1.0 ppm lead in milk, and precision of the method expressed by relative standard deviation of duplicate pairs ranged from 30% at 0.1 micrograms/mL to 3% at 1.0 micrograms/mL of lead in milk. The method compares favorably with the AOAC official first action anodic stripping voltammetric method (25.074). In addition, the method appears to work equally well for skim evaporated milk, sweetened condensed milk, and nonfat powdered dry milk when the latter two are reconstituted with water according to product label instructions. Recovery and interference studies are presented.
所介绍的方法描述了对炼乳中铅的直接测定，该方法省去了分析前的牛奶灰化步骤。数字仪器读数单位为微克铅/毫升牛奶。仪器校准后，每个样品的总分析时间少于3分钟。该方法的测定范围为牛奶中铅含量0.05 - 1.0 ppm，方法的精密度以重复样品对的相对标准偏差表示，牛奶中铅含量为0.1微克/毫升时为30%，1.0微克/毫升时为3%。该方法与美国官方分析化学师协会（AOAC）的首次批准阳极溶出伏安法（25.074）相比具有优势。此外，当按照产品标签说明用水复溶后，该方法对脱脂炼乳、加糖炼乳和全脂奶粉似乎同样有效。文中还介绍了回收率和干扰研究。
