Method Study On Determination Of Lincomycin In Honey

Lincosamide antibiotic drug,Lincomycin,which can inhibit Gram-positive bacteria effectually.lincomycin was widely used in beekeeping,especially American foulbrood(AFB).To protect customers' health,it is necessary to develop an adequate analytical procedures to determine lincomycin residue in honey.Up to now,two simple analytical methods based on high performance liquid chromatograph(HPLC) and high performance liquid chromatograph-electrospray tandem mass spectrometry(LC-ESI -MS/MS) have been developed,for determination of lincomycin antibiotic in honey.1.A simple and rapid method of determination of lincomycin residue in honey by HPLC was developed.The analytes was extracted,and cleaned-up by a single solid-phrase extraction step.The chromatographic separation of analytes was performed on an C₁₈ (5μm,250mm×4.6mm i.d.) reversed-phase column using a borax buffer solution(pH5.0)-mathnol -acetonitrile(70:26:4) as the mobile phase,at a flow rate 1.0mL/min.Injection volumn is 20μL,ultraviolet detection at 204nm wavelength.The retention time of lincomycin is 6.9 min.The linear ranges were from 1.0μg.mL^-1 to 20.0μg·mL^-1 for lincomycin and the correlation coefficients(r²)were all greater than 0.999 93.The average recoveries for lincomycin ranged were 93.02±1.22%.In replicate sets of honey samples spiked with the drug concentration of 2.5,5.0,and 10.0μg·g^-1,and the relative standard deviations(RSDs)were less than 1.58%for intra-day and 1.49%for inter-day determinations.The method detection limit is 75ng·g^-1.2.An analytical method for the determination of lincomycin residue by LC-ESI-MS/MS in honey was developed.In the procedure a solid-phase extraction for the isolation of lincomycin from diluted honey samples was employed.The residue of lincomycin was subsequently analyzed by reversed—phase high performance liquid chrom atography coupled with electrospray tandem mass spectrometry.Mass spectral acquisition was applied with multiple reaction monitoring of two diagnostic transition reactions.The qualitative analysis was based on the retention time,the precursor ion and two product ions,and the quantitation was carried out with intension of the characteristic ion m/z126. The linear ranges were from 1.0 ng·mL^-1 to 20.0 ng·mL^-1 for lincomycin and the correlation coefficients(r²)were all greater than 0.999 6.The average recoveries for lincomycin ranged were 95.1±3.3%.In replicate sets of honey samples spiked with the drug concentrations of 2.5,5.0 and 10.0 ng·g^-1,and the relative standard deviations(RSDs)were less than 5.3% for intra-day and 8.5%for inter-day determ inations.The method detection limit was 0.1 ng·g^-1. The methods are simple and rapid for determination of licomycin residue in honey, with acceptable recoveries and repeatability and an adequate limit of determination.