Synthesis and Evaluation of a Magnetic Molecularly
Imprinted Polymer Sorbent for Determination of Trace
Trichlorfon Residue in Vegetables by Capillary
DEQING LI, XUGUANG QIAO, JUXIU LU, ZHIXIANG XU
College of Food Science and Engineering, Shandong Agricultural University, Tai’an 271018, China
Correspondence to: Zhixiang Xu; e-mail: email@example.com.
Received: March 7, 2016
Accepted: July 2, 2016
In this study, a magnetic molecularly imprinted polymer (MMIP) based on Fe
was synthesized using trichlorfon as template molecule, methacrylic acid (MAA) as the functional monomer, and ethylene glycol
dimethacrylate (EGDMA) as the cross-linker. The prepared MMIP was characterized, and the results showed that it exhibited good
recognition and selective ability, offered a faster kinetics for the adsorption of trichlorfon. Scatchard analysis indicated that the
binding sites in the CdTe@MMIP had two distinct groups (the high and low afﬁnity binding sites). The saturated adsorption
) was 63.2 mg/g due to the low afﬁnity binding sites, and another saturated adsorption capacity (Q
71.4 mg/g due to the high afﬁnity binding sites. Using it as sorbent, a method of molecularly imprinted magnetic solid-phase
extraction coupled with capillary electrophoresis (MIMSPE-CE) for selective extraction, magnetic separation, and fast determination
of trace trichlorfon in vegetable samples was developed. Under optimal conditions, appreciable sensitivity was achieved with a
LOD of 30 lg/kg (S/N = 3) for the developed method. The relative standard deviation (RSD) for ﬁve replicate extractions of
0.05 mg/L trichlorfon standard solution was 4.2%. To evaluate the accuracy of this method, the blank cucumber and cauliﬂower
samples spiked with trichlorfon were extracted and analyzed by this method with good recoveries ranging from 78.7% to 96.6%.
Moreover, this method was applied to the quantitative detection of the trichlorfon residues in rape samples, and the results corre-
lated well with that obtained from the gas chromatography method. © 2016 Wiley Periodicals, Inc. Adv Polym Technol 2018, 37,
21745; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21745
Capillary electrophoresis, Magnetic solid-phase extraction, Molecular imprinting technology, Trichlorfon
ith the world population increasing, organophospho-
rus pesticides are widely applied in agriculture to
ensure adequate food yields. However, their extensive use
also gives rise to pesticide residues in agricultural products,
which are harmful to human health because of their high toxi-
Therefore, it is crucial to develop a sensitive and effec-
tive method for monitoring and controlling the pesticide
residues in foods.
In the past decades, many different technologies have been
reported for the detection of organophosphorus pesticides,
such as gas chromatography with ﬂame photometric detection
gas chromatography coupled with tandem mass
high-performance liquid chromatogra-
phy (HPLC) with ultraviolet visible detector
or coupled with
tandem mass spectrometry,
capillary electrophoresis (CE) with a ultraviolet visible or QD/
Among these methods, CE has proven to be
an attractive analysis technique for various applications due
to its major advantages of high efﬁciency and resolution, fast
analysis, and low consumption of reagents and solvents.
Unfortunately, CE has poor sensitivity, which is insufﬁcient
for direct determination of trace pesticide residues. Conse-
quently, an efﬁcient separation and preconcentration step is
usually needed prior to CE analysis.
To date, many pretreatment techniques have been used for
detecting the pesticides residues in agricultural products
including solid-phase extraction (SPE),
liquid–liquid extraction (LLE),
persive liquid–liquid microextraction (DLLME),
ﬂuid extraction (SFE),
matrix solid-phase dispersion
, and stir bar sorptive extraction.
SPE has been
recognized as the principal and high efﬁcient pretreatment
technique, and is usually applied to concentrate the
Xuguang Qiao and Deqing Li contributed equally to this work.
Advances in Polymer Technology, Vol. 37, No. 4, 2018, DOI 10.1002/adv.21745
© 2016 Wiley Periodicals, Inc.
21745 (1 of 9)