Development of carbohydrate functionalized magnetic nanoparticles for aminoglycosides magnetic solid phase extraction.

Magnetic nanoparticles decorated with d-galactose and galactitol (FeO@SiN-galactose and FeO@SiN-galactitol) were synthesized and employed as sorbent in a magnetic solid phase extraction (MSPE) procedure prior the analysis of aminoglycosides (AGs) in honey samples by LC-MS/MS. AGs are broad spectrum antibiotics, characterized by aminosugars, widespread used in therapeutic and veterinary applications. AGs can be found in the environment and food of animal origin. FeO@SiN-galactose and FeO@SiN-galactitol were synthesized via copper catalyzed alkyne azide cycloaddition and the synthesis was efficiently followed by infrared spectroscopy. They were characterized by electron microscopy, thermogravimetric analysis and magnetization curves. The nature of the loading (acetonitrile:water, 50:50 v/v) and elution solution (formic acid 190 mM) were studied in order to optimize the MSPE. Quantitative difference between MSPE with FeO@SiN-galactose and MSPE with FeO@SiN-galactitol in terms of recovery was found. The final optimized method using FeO@SiN-galactose and FeO@SiN-galactitol was applied in the determination of AGs in honey. The MSPE performance of FeO@SiN-galactitol was found to be superior to that of MSPE with FeO@SiN-galactose. The limits of quantification were between 2 and 19 μg kg for amikacin, dihydrostreptomycin, tobramicyn and gentamycin. A good correlation between predicted and nominal values of AGs in honey was found (trueness from 84% to 109%). This MSPE procedure not only requires a minimum amount of sorbent (1 mg) and sample (0.2 g), but it can also be accomplish in a rather short time.