基于Cr(Ⅵ)-8-羟基喹啉对鲁米诺-H2O2化学发光体系的催化作用,建立了测定Cr(Ⅵ)的化学发光法.检出限为1.2×10-3mg·L-1,线性范围为3.0×10-3-4.0×10-2mg·L-1,回归方程为ICL=3.6+1.68×106 C(g·L-1),相对标准偏差2.8%(n=11)；将该法应用于丙酸钙、动物蛋白粉等生化产品中痕量铬的测定,加标回收率96%-105%,5次测定平均值与苯二碳酰二肼光度法相比较,相对偏差小于5%,并探讨了化学发光反应机理.

It was found that in an alkaline medium of KOH,the chemiluminescence (CL) reaction between luminol and H2O2 was catalyzed by the complex formed by Cr(Ⅵ) with 8-hydroxyquinoline,and that linear relationship between the intensity of CL and the concentration Cr(Ⅵ) ion was kept in the range of 3.0×10-3 to 4.0×10-2 mg·L-1,having its linear regression equation as ICL=3.6+1.68×106C (g·L-1) with correlation coefficient of 0.999.Detection limit of this method was found to be 1.2×10-3mg·L-1 for Cr(Ⅵ),under the condition of K=3 and confidential level of 99.6%.Test of precision was made at the concentration level of 2×10-2mg·L-1 of Cr(Ⅵ) for 11 multiplicate determinations,and the RSD′s obtained was 2.8%.In the application of this method to the determination of Cr(Ⅵ) in samples of calcium propionate and animal protein powder,results obtained were in consistency with the results obtained by photometry.RSD′s (n=5) found were less than 3.2%,and recovery tested by the standard addition method gave results in the range of 96% to 105%.A brief discussion on the reaction methanism was also given.