HPLC法测定水溶性肥料植物生长调节剂的不确定度评定

为确保实验室分析的准确性和可靠性,减少实验室误差,采用HPLC法测定水溶性肥料中脱落酸、萘乙酸、氯吡脲、烯效唑4种植物生长调节剂的含量,通过分析试验方法、标准物质、仪器设备、样品前处理过程以及测量过程中的不确定度来源,从人、仪器、物料、方法、环境等5个方面进行不确定度评定,建立HPLC法测定水溶性肥料中植物生长调节剂的不确定度模型。结果表明,通过对不确定度的校准,水溶性肥料中脱落酸的含量表示为w±（-5.232 5w +0.158 5）（置信区间为95%,k=2）,萘乙酸含量为w±（-1.633 4w +0.101 3）（置信区间为95%,k=2）,氯吡脲含量为w±（-0.262 7w +0.034 4）（置信区间为95%,k=2）,烯效唑含量为w±（-0.144 5w+0.034 3）（置信区间为95%,k=2）。水溶性肥料中脱落酸、萘乙酸、氯吡脲、烯效唑测定结果的不确定度主要来源于标准曲线的拟合和样品的重复测定,而标准物质纯度、样品称量、样品前处理等引入的不确定度对最终合成不确定度影响不显著。脱落酸、萘乙酸、氯吡脲、烯效唑含量的扩展不确定度随含量的增加呈线性变化,扩展不确定度随含量的升高而降低。研究结果为水溶性肥料行业的健康发展提供技术保障。

Evaluation of Uncertainty in Determination of Plant Growth Regulators in Water-soluble Fertilizers by HPLC

In order to ensure the accuracy and reliability of laboratory analysis and reduce laboratory errors, the contents of abscisic acid, 1-naphthylacetic acid, chlorfenuron and uniconazole in water-soluble fertilizer were determined by HPLC. By analyzing the uncertainty sources of test methods, standard materials, instruments and equipment, sample pretreatment and measurement process, the uncertainty was evaluated from five aspects: human, machine, material, method and environment, and the HPLC method was established to determine the uncertainty evaluation model of plant growth regulators in water-soluble fertilizer. The results showed that the content of abscisic acid in water-soluble fertilizers was expressed as w±（-5.232 5w + 0.158 5） (confidence interval 95%, k=2), the content of 1-naphthylacetic acid was w±（-1.633 4w +0.101 3） (confidence interval 95%, k=2), the content of forchlorfenuron was w±（-0.262 7w +0.034 4） (confidence interval 95%, k=2), and the content of uniconazole was w±（-0.144 5w +0.034 3） (confidence interval 95%, k=2). The main sources of uncertainty affecting the results of abscisic acid, 1-naphthylacetic acid, forchlorfenuron and uniconazole in water-soluble fertilizers were the fitting of standard curve and repeated determination of samples, while the uncertainty introduced by referrence substance purity, sample weighing and sample pretreatment had no significant influence on the uncertainty of final synthesis. The expanded uncertainty of abscisic acid, 1-naphthylacetic acid, forchlorfenuron and uniconazole content changed linearly with the increase of content, and decreased with the increase of content. The research results provided technical support for the healthy development of water-soluble fertilizer industry.