摘要
建立基于智能手机与自制比色装置的数字图像比色法完成对水中氨氮的快速测定。以水杨酸钠为显色剂,三聚氰酸二氯钠为氧化剂,亚硝基铁氰化钠为催化剂,在碱性条件下与水中氨氮反应生成蓝色化合物,通过正交试验对反应条件进行优化。通过自制数字图像比色装置对显色溶液进行手机拍照分析,将经过色彩选择器(color picker)软件获得的RGB值和空白值基础上计算得出的欧氏距离D值应用于图片比色,对氨氮进行定量测定。氨氮质量浓度在0.05~2.0 mg/L与D值呈线性关系,相关系数(r)为0.998,检出限为0.03 mg/L,测定下限为0.12 mg/L。以空白水样为基体进行加标回收试验,氨氮回收率为98.7%~106.0%,测定结果的相对标准偏差为1.1%~7.4%(n=6)。实际样品该法分析结果与分光光度法基本一致。该方法可用于水样中氨氮的现场快速测定。
A digital image colorimetric method was established for the rapid determination of ammonia nitrogen in water by a smartphone and a self-made colorimetric device.Sodium salicylate was used as color developer,sodium dichloride cyanurate was used as oxidant,sodium nitroferricyanide was used as catalyst,the above reagents reacted with ammonia nitrogen in water under alkaline conditions to form a blue compound.The reaction conditions were optimized by orthogonal experiments.According to the self-made digital image colorimetric device,the color developing solution was photographed and analyzed by mobile phone,and the Euclidean distance D value calculated on the basis of the RGB value and blank value obtained by the color picker software was applied to the picture colorimetric,and the ammonia nitrogen was quantitatively determined.The values of D and mass concentration of ammonium nitrogen had good linear relationship in the range of 0.05-2.0 mg/L,and the correlation coefficient(r)was 0.998.The detection limit and the lower detection limit of the method was 0.03,0.12 mg/L,respectively.The recovery test of standard addition method was carry out by using blank water sample,and the recovery was in the range of 98.7%-106.0%,and the relative standard deviation of determined values was 1.1%-7.4%(n=6).Through the analysis of the actual samples,the results were basically consistent with the spectrophotometry.This method can be used for the rapid on-site determination of ammonia nitrogen in water samples.
作者
蔡璐
李春野
谷仕敏
CAI Lu;LI Chunye;GU Shimin(Physical and Chemical Laboratory of Nanjing Center for Disease Control and Prevention,Nanjing 210003,China)
出处
《化学分析计量》
CAS
2023年第5期18-22,共5页
Chemical Analysis And Meterage
关键词
数字图像比色法
智能手机
氨氮
快速测定
digital image colorimetry
smart phone
ammonia nitrogen
rapid detection
