Thiex Nancy J
Thiex Laboratory Solutions, 46747 214th St, Brookings, SD 57006.
J AOAC Int. 2016 Jul;99(4):914-922. doi: 10.5740/jaoacint.16-0050.
A previously validated method for the determination of both citrate-EDTA-soluble P and K and acid-soluble P and K in commercial inorganic fertilizers by inductively coupled plasma-optical emission spectrometry was submitted to the expert review panel (ERP) for fertilizers for consideration of First Action Official Method(SM) status. The ERP evaluated the single-laboratory validation results and recommended the method for First Action Official Method status and provided recommendations for achieving Final Action. Validation materials ranging from 4.4 to 52.4% P2O5 (1.7-22.7% P) and 3-62% K2O (2.5-51.1% K) were used for the validation. Recoveries from validation materials for citrate-soluble P and K ranged from 99.3 to 124.9% P and from 98.4 to 100.7% K. Recoveries from validation materials for acid-soluble "total" P and K ranged from 95.53 to 99.40% P and from 98.36 to 107.28% K. Values of r for citrate-soluble P and K, expressed as RSD, ranged from 0.28 to 1.30% for P and from 0.41 to 1.52% for K. Values of r for total P and K, expressed as RSD, ranged from 0.71 to 1.13% for P and from 0.39 to 1.18% for K. Based on the validation data, the ERP recommended the method (with alternatives for the citrate-soluble and the acid-soluble extractions) for First Action Official Method status and provided recommendations for achieving Final Action status.
一种先前经验证的方法，通过电感耦合等离子体发射光谱法测定商业无机肥料中柠檬酸 - 乙二胺四乙酸（citrate - EDTA）可溶性磷和钾以及酸溶性磷和钾，该方法已提交给肥料专家评审小组（ERP），以考虑作为首次行动官方方法（SM）的地位。ERP评估了单实验室验证结果，并推荐该方法作为首次行动官方方法的地位，并为实现最终行动提供了建议。验证材料中五氧化二磷（P2O5）含量范围为4.4%至52.4%（磷含量为1.7%至22.7%），氧化钾（K2O）含量范围为3%至62%（钾含量为2.5%至51.1%），用于验证。柠檬酸可溶性磷和钾的验证材料回收率范围为磷99.3%至124.9%，钾98.4%至100.7%。酸溶性“总”磷和钾的验证材料回收率范围为磷95.53%至99.40%，钾98.36%至107.28%。柠檬酸可溶性磷和钾的r值（以相对标准偏差表示），磷的范围为0.28%至1.30%，钾的范围为0.41%至1.52%。总磷和钾的r值（以相对标准偏差表示），磷的范围为0.71%至1.13%，钾的范围为0.39%至1.18%。基于验证数据，ERP推荐该方法（包括柠檬酸可溶性和酸溶性萃取的替代方法）作为首次行动官方方法的地位，并为实现最终行动地位提供了建议。
