Single pot in situ aqueous derivatization and subsequent determination of streptomycin and dihydrostreptomycin residues in honey by means of mass spectrometry

Abstract

Streptomycin (STR) and dihydrostreptomycin (DSTR) are the typically encountered aminoglycoside (AMG) residues in honey. For AMG analysis, studies in literature involve impractical and expensive applications such as ion-pairing chromatography, immunoassays, pre and post column derivatizations, or SPE approaches. Pretreatments of these methods are toilsome and costly. Herein, one-pot, aqueous in-situ derivatization method was presented as a superior protocol. Time and cost-efficient UHPLC-MS/MS method has been developed, and practical sample preparation was introduced. Satisfactory results were reported in method verification studies. The mean recovery values were 102.6% for STR and 101.3% for DSTR. Average values between 1.5% and 9.9% RSDs were found at intra and inter-day precisions. CCα (5.7 and 5.8 μg/kg) and CCβ (6.2 and 6.4 μg/kg) values were calculated for STR and DSTR respectively. AMG residues were found in 29 out of 110 analyzed samples using validated method. Described novelty enabled comprehensive analysis in an inexpensive and straightforward manner.

Keywords: Aminoglycosides; Honey; In situ derivatization; Residue; UHPLC-MS/MS.