A Solid‐phase Spectrophotofluorimetry for the Determination of Trace Amount of Nitrite in Food Samples with Rhodamine B

Abstract

A simple and sensitive solid‐phase fluorescence quenching method for the determination of trace amounts of nitrite in food samples has been developed. The method is based on that rhodamine B (RhB) which is used as an emission reagent and is included by β‐cyclodextrin polymer(β‐CDP), reacts with nitrite in the presence of iodide to form a nonfluorescence compound in acidic medium. The fluorescence intensity of the RhB‐included β‐CDP was measured in solid phase with excitation and emission wavelengths of 353 and 592 nm, respectively. The fluorescence quenching degree is good linear with the concentration of nitrite over the ranges of 1.0–3.0 µg with a detection limit of 0.04 µg and RSD is 1.2%. The general coexisting ions do not interfere to the reaction of RhB with nitrite. The proposed method has been applied to the determination of trace amount of nitrite in food samples with the recoveries of 102.8% (ham) and 99.0% (sausage), respectively.

Keywords:

• Nitrite
• solid‐phase fluorescence
• fluorescence quenching
• rhodamine B

Notes

This work was supported by the Natural Science Foundation of Tianjin, China.