摘要
利用鲁米诺 铁氰化钾 尿酸化学发光体系,在酸性介质中,亚硝酸根氧化亚铁氰化钾为铁氰化钾,从而建立了一种间接测定痕量亚硝酸根的新方法。讨论了酸度、反应物浓度、干扰离子等因素的影响。方法的检出限为5.0×10-11g·ml-1,对样品进行了平行测定(n=11),其相对标准偏差为2.2%～3.9%,线性范围为1.0×10-9～1.0×10-5g·ml-1。方法简便,易于操作,并具有较高的灵敏度和选择性。用于食品中亚硝酸根的测定,回收率为93.5%～108.0%,结果满意。
Based on the chemiluminescence reaction among luminol, potassium ferricyanide and uric acid, trace amounts of nitrites in foodstuffs were satisfactorily determined. Before the chemiluminescence reaction, NO-2 in the sample was reacted with Fe(CN)4-6 to give Fe(CN)3-6 at an acidity of 0.06mol·L-1 HCl. Then the reaction mixture was led into the chemiluminescence reaction cell to react with luminol in the presence of uric acid and in this reaction, the solution was made to an alkalinity of 0.5mol·L-1 NaOH. Under the optimum reaction conditions the intensity of the chemiluminescence produced was directly proportional to the concentration of NO-2, and linearity was obtained in the range of 1.0×10-9～1.0×10-5g·L-1 of NO-2 ion. The detection limit of the method was found to be 5.0×10-11g·L-1(3S). RSD′s (n=11) obtained from the results in the analysis of some foodstuff samples were in the range of 2.2% to 3.9%, and the recoveries were in the range of 93.5% to 108.0%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2003年第9期515-516,518,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
