鲁米诺/二氧化硫脲流动注射化学发光灵敏检测亚硝酸钠OA

Sodium nitrite(NaNO2)is widely used as a food additive.Long-term excessive intake of NaNO2 may induce diseases such as gastric cancer,while acute overconsumption can lead to methemoglobinemia which shows severe acute poisoning symptoms.Therefore,rapid and accurate detection of NaNO2 is crucial for preventing acute poisoning as well as monitoring long-term excessive intake-induced diseases.Chemiluminescence(CL)is a method which has advantages of compact instrumentation,simplicity of detection,and high sensitivity.Combining with the benefits of using thiourea dioxide as a luminol co-reagent to enhance the stability and selectivity of the CL system,a luminol/thiourea dioxide flow injection CL system was employed for quantitative analysis of NaNO2.The significant reduction in luminescence upon addition of NaNO2 demonstrated the feasibility of this analytical method.Optimal detection conditions were further established by optimizing solution pH value and flow rate of peristaltic pump.The system was proved suitable for quantifying NaNO2 from 10 nmol/L to 5 mmol/L,with a detection limit(S/N=3)of 3.5 nmol/L.The linear correlation coefficient(r)was 0.9971.A relative standard deviation of 4.36%was obtained for nine consecutive injections of 10 μmol/L NaNO2,indicating a good reproducibility.Furthermore,the addition of six representative interferents showed no significant effect on CL intensity,indicating a good selectivity.