荧光探针8-(3’,4’-二氨基苯)-二氟化硼-二吡咯甲烷用于光度法 灵敏测定食品中亚硝酸根和硝酸根

新型荧光探针8-(3’,4’-二氨基苯)-二氟化硼-二吡咯甲烷本体荧光很弱, 在酸性条件下, 和亚硝酸盐于30 ℃下反应15min后生成强荧光的三氮唑产物. 硝酸根可通过锌粉和氯化镉还原成亚硝酸根. 由此建立了一种新的荧光光谱法灵敏测定食品中的亚硝酸根和硝酸根. 其线性范围为0.06～6 μmol•L－1. 当信噪比等于3时, 方法的检出限为2 nmol• L－1. 将该方法首次用于多种食品中亚硝酸盐和硝酸盐的测定, 加标回收率为98.16%～103.20%.

Sensitive Determination of Nitrate and Nitrite in Food Products by Spectrofluorimetry with a Fluorescent Probe: 8-(3',4'-Diaminophenyl)-difluoroboradiaza-s-indacence

The fluorescence of 8-(3’,4’-diaminophenyl)-difluoroboradiaza-s-indacene is very weak, but when it reacts with nitrite, a strong fluorescent triazole forms in aqueous medium at 30 ℃, which offers the advantages of specificity and sensitivity for the determination of nitrite. Nitrate can be reduced to nitrite by zinc and cadmium chloride. Based on this, a new method is developed for sensitive determination of nitrite and nitrate in food products by spectrofluorimetry. The response is a linear function of concentration in the range of 0.06～6 μmol•L－1. The detection limit is 2 nmol•L－1 (S/N＝3). The proposed method has been used for the determination of trace level of nitrite and nitrate in food products with the recoveries of 98.16%～103.20%.