A novel fluorescent sensors for sensitive detection of nitrite ions

In this work, the fluorescent sensors based ternary ZnCdS quantum dots (QDs) were constructed for nitrite (NO2-) detection, and ternary ZnCdS QDs were synthesized by a rather facile, low-cost and effective aqueous synthesis method using air-stable compounds. Experimental results indicated that the ZnCdS QDs fluorescence (PL) emission intensity was decreased gradually with the introduction of NO2-. Importantly, the F/F-0 (F and F-0 were the PL intensity in the presence and absence of NO2- at 505nm, respectively) was linearly proportional to the NO2- to 700 mu M, the equation of linear regression was y = -0.123x+1.1525, which showed a better performance to the detection of NO2-. Moreover, there was no interference to other interfering substances including metal ions and anion ions. Thus, we applied the ZnCdS QDs fluorescence sensors to detect the contents of NO2- in ham sausage and the results showed that the contents of NO2- in ham sausage was 18.45 mg/kg. Therefore, this test method had the advantages of simplicity, rapidity and high sensitivity.