海带中碘含量的测定

Determination of Iodine Content in Kelp

本实验采用干式灰化法对市售干海带进行预处理,紫外分光光度法测定海带中碘含量。使用控制变量法对最佳氧化剂用量、显示剂用量、盐酸用量和显示时间等条件进行实验,实验结果为:最大吸收波长为600nm,盐酸的用量为1.50mL,氧化剂NaNO2的用量为0.40mL,显色时间为30min,显示剂淀粉用量为1.50mL。在最优条件下I-的含量在0~8μg/mL呈现良好的线性关系,线性回归方程为Y=0.0703X-0.0165,相关系数R2=0.9949,相对标准偏差为0.52%,加标回收率为94.51%~110.60%。研究结果为人们合理食用海带、补充人体所需碘元素提供参考。

In this experiment,the commercial dried kelp was pretreated by dry ashing method,and the iodine content in kelp was determined by ultraviolet spectrophotometry.The optimal dosage of oxidant,the dosage of display agent,the dosage of hydrochloric acid and the display time were tested with the method of control variable.The test results showed that the maximum absorption wavelength was 600nm,the dosage of hydrochloric acid was 1.50mL,the dosage of oxidant NaNO2was 0.40mL,the color developing time was 30min,and the dosage of starch was 1.50mL The linear relationship was good when the content of I-was 0~8μg/mL,the linear regression equation was Y=0.0703X-0.0165,the correlation coefficient R2=0.9949,the relative standard deviation was 0.52%,and the standard recovery was 94.51%~110.60%.The results provide a reference for the reasonable consumption of kelp and the supplementation of iodine.