催化动力学光度法快速测定青梅和杨梅中的痕量铅  

Catalytic Kinetic Spectrophotometry for Rapid Determination of Trace Lead in Green Plum and Bayberry

作　　者：王彦花 郭楠楠[1,2] 韩章华 赵风雨 WANG Yanhua;GUO Nannan;HAN Zhanghua;ZHAO Fengyu(College of Food Science and Engineering,Zhengzhou University of Science and Technology,Zhengzhou 450064,China;Zhengzhou City Food Safety Rapid Test Key Laboratory,Zhengzhou 450064,China;Henan Ambino Testing Technology Co.,Ltd.,Zhengzhou 450001,China)

机构地区：[1]郑州科技学院食品科学与工程学院,河南郑州450064 [2]郑州市食品安全快速检测重点实验室,河南郑州450064 [3]河南安必诺检测技术有限公司,河南郑州450001

出　　处：《食品科技》2022年第11期273-278,共6页Food Science and Technology

基　　金：郑州市科技局新兴产业研究开发计划项目(153PXXCY186);河南省高等学校重点科研项目(21B550008)。

摘　　要：在NaH_(2)PO_(4)-Na_(2)HPO_(4)缓冲液中,铅能催化过氧化氢氧化钙指示剂的褪色反应,由此可建立催化动力学光度法测定青梅和杨梅中痕量铅的最佳反应条件。通过单因素试验探究了催化反应体系的最适pH值、过氧化氢用量、钙指示剂用量、反应温度和反应时间对吸光度的影响,从而确定了测定青梅及杨梅中痕量铅的最佳反应条件为:pH值为6.4的NaH_(2)PO_(4)-Na_(2)HPO_(4)缓冲溶液5.0 mL、3%过氧化氢3.0 mL、0.1%钙指示剂2.0 mL、100℃水浴30 min,测定波长340 nm。该方法在铅浓度0~1.0μg/mL催化体系与非催化体系吸光度之差(ΔA)存在良好的线性关系,检出限为0.0048μg/mL,定量限为0.0159μg/mL,加标回收率为91.7%~101.9%。该方法测定青梅与杨梅中铅含量的结果与国标方法相比无显著性差异,相对标准偏差RSD(n=6)为0.522~1.117,可用于测定青梅和杨梅中的痕量铅。In the buffer solution of NaH_(2)PO_(4)-Na_(2)HPO_(4),lead can catalyze the fading reaction of calcium hydroxide indicator,which can establish the optimal reaction conditions for the determination of trace lead in green plum and bayberry by catalytic kinetic spectrophotometry.The effects of the optimum pH,the dosage of hydrogen peroxide,the dosage of calcium indicator,the reaction temperature and the reaction time on the absorbance of the catalytic reaction system were explored through single factor experiments,and the optimum reaction conditions for the determination of trace lead in green plum and bayberry were determined.The reaction condition is that:5.0 mL of NaH_(2)PO_(4)-Na_(2)HPO_(4)buffer solution with pH 6.4,3.0 mL of 3%hydrogen peroxide,2.0 mL of 0.1%calcium indicator,heated in a water bath at 100℃for 30min,and the measurement wavelength is 340 nm.This method has a good linear relationship between the absorbance difference(ΔA)of the catalytic system and the non-catalytic system in the range of lead concentration of 0~1.0μg/mL.The detection limit of the method is 0.0048μg/mL,and the quantification limit is 0.0159μg/mL,the recovery rate of standard addition was 91.7%~101.9%.Compared with the national standard method,the detection results of this method for the determination of lead in green plum and bayberry have no significant difference,and the relative standard deviation of the detection results is less than 1.2,which can be used for the determination of trace lead in green plum and bayberry.

关 键 词：催化动力学光度法 快速检测 铅 青梅 杨梅 

分 类 号：TS207.51[轻工技术与工程—食品科学]