Molecularly imprinted covalent organic polymers for the selective extraction of benzoxazole fluorescent whitening agents from food samples

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.

Section: Introductionmentioning

confidence: 99%

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

Tian

et al. 2022

“…In addition, a molecularly imprinted covalent organic polymer (MI‐COP) was prepared via non‐covalent imprinting for selective SPE of benzoxazole fluorescent whitening agents in food samples [107]. Tang et al.…”

Section: Applications Of Molecularly Imprinted Polymer‐based Spe To Rmentioning

confidence: 99%

Recent advances and applications of molecularly imprinted polymers in solid‐phase extraction for real sample analysis

Chen

Wang

et al. 2021

Sample pretreatment is essential for the analysis of complicated real samples due to their complex matrices and low analyte concentrations. Among all sample pretreatment methods, solid‐phase extraction is arguably the most frequently used one. However, the majority of available solid‐phase extraction adsorbents suffer from limited selectivity. Molecularly imprinted polymers are a type of tailor‐made artificial antibodies and receptors with specific recognition sites for target molecules. Using molecularly imprinted polymers instead of conventional adsorbents can greatly improve the selectivity of solid‐phase extraction, and therefore molecularly imprinted polymer‐based solid‐phase extraction has been widely applied to separation, clean up and/or preconcentration of target analytes in various kinds of real samples. In this article, after a brief introduction, the recent developments and applications of molecularly imprinted polymer‐based solid‐phase extraction for determination of different analytes in complicated real samples during the 2015‐2020 are reviewed systematically, including the solid‐phase extraction modes, molecularly imprinted adsorbent types and their preparations, and the practical applications of solid‐phase extraction to various real samples (environmental, food, biological, and pharmaceutical samples). Finally, the challenges and opportunities of using molecularly imprinted polymer‐based solid‐phase extraction for real sample analysis are discussed.

“…Four milliliters (10 μg/mL) AFB1 solution (prepared in methanol-water) was added into the tubes. The mixture was vigorously shaken at 2500 rpm for a series of time (1,2,3,6,9,12,15,20,25,30,35,40, and 60 min). The tubes were centrifuged and the supernatants were measured by HPLC.…”

Section: Dynamics Of Polymersmentioning

confidence: 99%

“…And MIPs were also combined with supporting materials to achieve better extraction effects. Such as, MIPs combined with covalent organic frameworks were applied in food and plants samples ; Amphiphilic magnetic MIPs were prepared and used to extract chloroacetamide herbicides and bisphenol A .…”

Section: Introductionmentioning

confidence: 99%

Combined biocompatible medium with molecularly imprinted polymers for determination of aflatoxins B1 in real sample

Song

Chen

et al. 2019

A kind of molecularly imprinted polymers modified with biocompatible medium was prepared by suspension polymerization. The obtained hybrid materials were used as the adsorbents for the solid‐phase extraction of aflatoxins B1 in real samples. A structural analog of the target, 6‐methyl‐4‐phenylchroman‐2‐one was used as the pseudo‐template, owing to their lower toxicity and cheaper price compared with aflatoxins B1; and methacrylic acid and glycidyl methacrylate were used as the co‐monomers. Scanning electron microscopy and size distribution analysis were used to characterize the obtained polymers. The extraction parameters were optimized to achieve the desired extraction performance. The polymer solid‐phase extraction coupled with high‐performance liquid chromatography was successfully applied to determine aflatoxins B1 from soy sauce without the process of protein removal. Under the optimum extraction conditions, the detection results of aflatoxins B1 in lab‐made column in soy sauce samples was carried out, with a recovery rate of 96%. The established method presented a linear range from 10 to 1000 ng/mL with the coefficient of determination of 0.9994 and the limit of detection of 0.05 ng/mL. Likewise, the inherent selectivity of lab‐made column towards aflatoxins B1, Ochratoxin A, and Zearalenone was demonstrated.