Amino functionalized magnetic covalent organic framework for magnetic solid‐phase extraction of sulfonylurea herbicides in environmental samples from tobacco land

Abstract

An amino-functionalized magnetic covalent organic framework composite TpBD-(NH 2 ) 2 @Fe 3 O 4 (Tp=Tp1,3,5-triformylphloroglucinol, BD-(NH 2 ) 2 is 3,3',4,4'-biphenyltetramine) was prepared by post-synthesis modification. Due to its abundant benzene rings and amino groups, large specific surface area and porous structure, the prepared TpBD-(NH 2 ) 2 @Fe 3 O 4 exhibits high extraction efficiency toward sulfonylurea herbicides. Based on this, a new method of magnetic solid-phase extraction with TpBD-(NH 2 ) 2 @Fe 3 O 4 as the sorbent combined with high-performance liquid chromatography and ultraviolet detection was developed for trace analysis of sulfonylurea herbicides in environmental water, soil and tobacco leaves samples from tobacco land. Under the optimized conditions, the limits of detection within 0.05-0.14 μg/L were achieved with a high enrichment factor of 217-260-fold, and the relative standard deviations were 4.9-7.5% (n = 7, c = 0.5 μg/L). The linear range was around three orders of magnitude with the square of correlation coefficient higher than 0.9936. The method was applied to analyze five sulfonylurea herbicides in the environmental water, soil, and tobacco leave samples collected from tobacco land. No sulfonylurea herbicides were detected in these samples. The recoveries of target sulfonylurea herbicides in spiked environmental water, soil, and tobacco leaf samples were found in the range of 90.7-104, 70.7-99.0, and 59.3-97.8%, respectively. The results illustrate that the established TpBD-(NH 2 ) 2 @Fe 3 O 4 -magnetic solid-phase extractionhigh-performance liquid chromatography-ultraviolet detection method is efficient for the analysis of trace sulfonylurea herbicides in environmental samples.

Facile synthesis of a novel magnetic covalent organic frameworks for extraction and determination of five fungicides in Chinese herbal medicines

“…For example, Gong et al [26] have prepared magnetic COFs (TpBD@Fe 3 O 4 ) for the detection the sulfonamides in animal-derived foods. Tian et al [27] have synthesized amino-functionalized magnetic COFs (TpBD-(NH 2 ) 2 @Fe 3 O 4 ) for the analysis of trace sulfonylurea herbicides in environmental samples. The established analytical method achieved low LODs and high enrichment factors (EFs).…”

“…Tian et al. [27] have synthesized amino‐functionalized magnetic COFs (TpBD‐(NH 2 ) 2 @Fe 3 O 4 ) for the analysis of trace sulfonylurea herbicides in environmental samples. The established analytical method achieved low LODs and high enrichment factors (EFs).…”

Fabrication of magnetic covalent organic framework for efficient extraction and determination of phthalate esters in milk samples

“…It is easy to separate magnetic adsorbents from liquid solution through a magnet, which avoids cumbersome centrifugation, filtration steps, or tedious SPE column packing procedures. The key point for the application of MSPE is the development of magnetic adsorbent materials [15]. Covalent organic frameworks (COFs) are a class of organic porous materials constructed from organic monomers whose backbone is composed entirely of light elements (C, H, O, and N) by covalent bonding.…”

Titanium‐based metal‐organic framework MIL‐125(Ti) for the highly selective isolation and purification of immunoglobulin G from human serum

“…It is mainly used for sample separation, purification, and enrichment before drug analysis, food analysis, environmental analysis, and chemical engineering [7][8][9][10]. So far, a series of adsorbents have been used in SPE, such as metal-organic frameworks (MOFs), carbon nanotubes, graphene and graphene oxide, silicon-based adsorbents, molecularly imprinted polymers, and so forth [11][12][13][14][15][16][17]. More and more research on protein separation and purification depends on the development of new adsorbents.…”