Ionic Liquid-Functionalized Magnetic Metal–Organic Framework Nanocomposites for Efficient Extraction and Sensitive Detection of Fluoroquinolone Antibiotics in Environmental Water

Abstract

Herein, the hydrophobic carboxyl-functionalized ionic liquid (IL-COOH) was encapsulated into the prepared Fe3O4@Zr-MOFs, and the novel water-stable IL-COOH/Fe3O4@Zr-MOF nanocomposites were first synthesized. The polydopamine-functionalized Fe3O4 was introduced to construct the core–shell structure via layer-by-layer modification, and the controlled growth of Zr-MOFs was achieved, which realized the adjustment of charged properties of nanocomposites and simplified the adsorption or extraction process. The IL-COOH/Fe3O4@Zr-MOFs were fully studied by IR, HNMR, XRD, N2 adsorption–desorption isotherms, TEM, EDS mapping, VSM, and so on. Then, they were employed for the selective adsorption and detection of fluoroquinolone antibiotics (FQs). The adsorption isotherms and kinetics demonstrated that the adsorption process followed a pseudo-second-order kinetic model and the Langmuir isotherm model. Among them, IL-COOH/Fe3O4@UiO-67-bpydc showed the best adsorption performance, and the maximum adsorption capacity of ofloxacin was 438.5 mg g–1. Coupled magnetic solid-phase extraction with HPLC-DAD, a convenient, sensitive, and efficient method for extraction and detection of FQs in environmental water, was developed based on IL-COOH/Fe3O4@UiO-67-bpydc. The recoveries of environmental water were ranging from 90.0 to 110.0%, and the detection limits were lower than 0.02 μg L–1. The novel functionalized composites served as solid-phase adsorbents and liquid-phase extractants. This study also provided a promising strategy for designing and preparing multi-functionalized nanocomposites for the removal or detection of pollutants in environmental samples.

Core‐shell magnetic porous organic polymer for magnetic solid‐phase extraction of fluoroquinolone antibiotics in honey samples followed by high‐performance liquid chromatography with fluorescence detection

“…The analytical performance of this method was compared with other methods reported for analysis of FQs, which are listed in Table S3. The LODs of this method were comparatively lower than [16,17,26–31] and equivalent to those reported [9,32]. The extraction efficiency of this method was up to 84.4–91.7%, which was significantly higher than that reported earlier [9].…”

“…While the adsorption efficiency showed a downward trend in the range of pH 8.0–12.0. FQs were amphoteric strong polar acid compounds, and their p K a1 and p K a2 values were between 5.7–6.2 and 8.0–9.8, respectively [26]. To explain the adsorption behavior of five FQs on HQ‐TAPB@Fe 3 O 4 MNPs, the Zeta potential of HQ‐TAPB@Fe 3 O 4 MNPs in the range of pH 2–12 was characterized (Figure 3B).…”

“…Since FQs were amphoteric acidic compounds [26] and their adsorption efficiency decreased when pH was higher than 8 (as shown in Figure 3A), the alkaline condition was more conducive to the desorption of FQs. First, 10 mmol/L NaOH mixed with methanol, ACN, and acetone with a volume ratio of 8:2, respectively, were used as eluents for desorption of FQs retained on HQ‐TAPB@Fe 3 O 4 MNPs.…”

Fabrication of Magnetic Al-Based Fe3O4@MIL-53 Metal Organic Framework for Capture of Multi-Pollutants Residue in Milk Followed by HPLC-UV

“…The black line represents the characteristic diffraction peak of amino-modified Fe 3 O 4 magnetic materials. When 2θ = 30.12°,35.6°,43.2°,53.4°,57.1° and 62.7°, the characteristic diffraction peak of the amino-modified Fe 3 O 4 magnetic materials of Fe-O can be clearly observed [ 27 ]. The red line represents the characteristic diffraction peak of the H 2 BDC-modified magnetic material.…”

Nanomaterials with Excellent Adsorption Characteristics for Sample Pretreatment: A Review

“…A method for the synthesis of novel magnetic nanocomposites was reported by Lu and co-workers [ 111 ]. Fe 3 O 4 particles functionalized by polydopamine was grafted onto Zr-MOF by layer modification, and then the hydrophobic carboxyl functionalized ionic liquids (IL-COOH) were coated onto the Fe 3 O 4 @Zr-MOF magnetic particles, and the novel IL-COOH/Fe 3 O 4 @Zr-MOF magnetic nanocomposites were obtained ( Figure 12 ).…”