摘要目的 采用均匀设计法优化食品中碘的碱灰化-砷铈催化分光光度法的最佳测定条件.方法 根据现行食品中碘的碱灰化测定法,用均匀设计U*8(84)表安排实验条件(碳酸钾和硫酸锌混合液、氯酸钾和氯化钠混合液、灰化温度、灰化时间),测定大豆中的碘含量,并计算回收率,建立回收率和各测定条件的数学模型,计算测定条件的最优组合,最后使用该组合平行3次测定大豆中的碘含量,进行验证.结果 测定条件的最优组合为:碳酸钾和硫酸锌混合液1.5 ml,氯酸钾和氯化钠混合液1.5 ml,灰化温度550℃,灰化时间4.5 h.3次大豆碘含量测定的平均回收率为101.6％.结论 均匀设计法找到的最优测定条件的组合应用于食品(大豆)中碘的测定,结果满意.

abstractsObjective To apply a uniform design method to optimize the experimental conditions for iodine determination in foods by alkaline ashing-As3+-Ce4+ catalytic spectrophotometric method.Methods According to the current method for determination of food iodine,uniform design table U*8 (84) for experimental conditions was set up as(K2CO3-ZnSO4 mixed solution,KClO3-NaCl mixed solution,ashing temperature,ashing time),iodine content in soybean was determined,and recovery rate was calculated.Mathematical model of recovery rate and various test conditions was established.Optimal combinational assay conditions were calculated.As a verification test,the optimal combinational assay was repeatedly used to determine iodine content in soybean for 3 times.Results The optimal combination for determination conditions was:K2CO3-ZnSO4 mixed solution 1.5 ml and KClO3-NaCl mixed solution 1.5 ml,ashing temperature 550 ℃ and ashing time 4.5 h.The average recovery rate for determination of iodine content in soybean was 101.6％ for the 3 times.Conclusion The optimal combination of determination conditions by uniform design is used in determination of iodine content of food(soybean) with satisfactory results.