Synthesis of Bifunctionalized Mesoporous Silica and Its Application in the Detection of Aminoglycosides

Abstract

In this work, a novel reversed phase/cation exchange mixed-mode sorbent for solid phase extraction (SPE) was synthesized by modifying the mesoporous material MCM-41 with 3-aminopropyltriethoxysilane (APTES) and octadecyltrimethoxysilane (C18 TMS) followed by succinic acid glycoside (SAA) in two steps. Various SPE parameters were optimized, and an analytical method was developed for the determination of six aminoglycosides (AGs) in milk by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) using an amide column for chromatographic separation. The results of structural characterization demonstrated that the synthesized material had a large specific surface area, uniform pore size, and modified functional groups, exhibiting strong adsorption capacity and selectivity for AGs. The bifunctionalized material significantly improved matrix interference of milk compared to the carboxylated material. The proposed method exhibited good linearity for the six AGs in the concentration range of 5–500 ng/mL with correlation coefficients of 0.992 7–0.999 5. The limits of detection (LOD) achieved using this method were 0.30–2.50 ng/mL. The average recoveries ranged from 74.3% to 107% with relative standard deviation (RSD) between 2.6% and 15.7%. The material is characterized by low cost, simple preparation and good operability as a SPE filler. It can be extended to the detection of AGs in other food or agricultural samples.

Keywords

• mesoporous materials; mcm-41; solid phase extraction; aminoglycosides; ultra-high performance liquid chromatography-tandem mass spectrometry; matrix effects; milk