Simultaneous determination of norfloxacin and lomefloxacin in milk by first derivative synchronous fluorescence spectrometry using Al (III) as an enhancer.
A novel method for the simultaneous determination of norfloxacin (NFLX) and lomefloxacin (LFLX) in milk samples was developed by using first derivative synchronous fluorimetry. The synchronous fluorescence (Δλ=160 nm) spectra and first derivative synchronous fluorescence spectra of NFLX, LFLX and their mixture were studied. The zero-crossing method was utilized to measure the first derivative value of the derivative spectrum. The zero-crossing points were located at 275.0 nm for NFLX and at 283.8 nm for LFLX, in first derivative synchronous fluorescence spectra. Therefore, 283.8 nm and 275.0 nm were selected for the determination of NFLX and LFLX. The first derivative values varied linearly with the concentrations in the range of 1.68×10(-8)-5.64×10(-6) mol L(-1) for NFLX and 1.89×10(-8)-6.19×10(-6) mol L(-1) for LFLX. The detection limits were 5.03×10(-9) mol L(-1) for NFLX and 7.58×10(-9) mol L(-1) for LFLX. The proposed method is reliable, selective and sensitive, and has been used successfully in the simultaneous determination of NFLX and LFLX in milk samples, whose results were in good agreement with those obtained by HPLC.
College of Public Health, University of South China, Hengyang, PR China.
Yan-Ni
YN
Yi
Gui-Rong
GR
Li
Yong-Sheng
YS
Wang
Yu-Zhen
YZ
Zhou
Hui-Min
HM
Zhu
D017607:Aluminum Compounds / Q000032:analysis* / Q000737:chemistry; D000818:Animals; D024841:Fluoroquinolones / Q000032:analysis* / Q000737:chemistry; D008892:Milk / Q000737:chemistry*; D009643:Norfloxacin / Q000032:analysis* / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods
D017607:Aluminum Compounds; D024841:Fluoroquinolones; C053091:lomefloxacin; D009643:Norfloxacin