Determination of Trace Neomycin Sulfate by Photoluminescence and Lanthanide Sensitized Fluorescence Quenching on Europium-norfloxacin-SDS

In the ammonia-ammonium chloride buffer solution of pH=7.4,europiumion(Eu3+) and norfloxacin(NFLX) react and combine as steady complex under room temperature.The complex shows its sensitized fluorescence of rare earth.The maximum excitation wavelength and maximum emission wavelength are 340 nm and 612 nm,respectively.The fluorescence intensity has a further increase in sodium dodecyl sulfate(SDS).When neomycin sulfate solution is added,the fluorescence intensity of the system of Eu3+-NFLX-SDS diminishes,while the locations of the excitation and emission wavelengths stay the same.According to this result,a new way to determine the concentration of neomycin sulfate is established.The concentration range that neomycin sulfate can detect is 0.909~22.7 mg/L.The detection limit is up to 0.4 mg/L.This measurement has been applied to determine neomycin sulfate in tablet and drops.The relative standard deviation is 1.4%~3.5% for 6 parallel determination of neomycin sulfate samples and the recovery is 90.5%~102.3%.