Determination of Gentamicin in Milk Using a New Metal–Organic Framework as a Dmspe Sorbent and Uhplc-Ms/Ms

Abstract

PCN-55(Zr), the first designed and synthesized metal–organic skeleton material, has great potential as a novel material for pretreatment. In this study, PCN-55(Zr) was thermal synthesized and applied for the first time in dispersive microsolid-phase extraction (DMSPE) for the enrichment of gentamicin (GEN) in milk samples. PCN-55(Zr) showed high adsorption capacity, fast kinetics, and easy regeneration for reuse and thus can be used as a promising adsorbent. The isothermal data were best fitted to the Freundlich model, the kinetics were consistent with a quasi-secondary kinetic model, and the adsorption mechanism was mainly attributed to interactions such as π-π stacking, hydrogen bonding, and electrostatic forces. The effects of pH, PCN-55(Zr) dosage, adsorption time, desorption solvent and time were also investigated. A simple, rapid, sensitive, inexpensive and solvent-consuming DMSPE method for ultrahigh-performance liquid chromatography–tandem mass spectrometry was developed and successfully used for the preconcentration and determination of GEN in milk samples.

Keywords: Metal-organic frameworks, Dispersive micro-solid phase extraction, gentamicins, Milk