Magnetic molecularly imprinted polymer nanoparticles for di‐(2‐ethylhexyl) phthalate were synthesized by surface imprinting technology with a sol–gel process and used for the selective and rapid adsorption and removal of di‐(2‐ethylhexyl) phthalate from aqueous solution. The prepared magnetic molecularly imprinted polymer nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and vibrating sample magnetometry. The adsorption of di‐(2‐ethylhexyl) phthalate onto the magnetic molecularly imprinted polymer was spontaneous and endothermic. The adsorption equilibrium was achieved within 1 h, the maximum adsorption capacity was 30.7 mg/g, and the adsorption process could be well described by Langmuir isotherm model and pseudo‐second‐order kinetic model. The magnetic molecularly imprinted polymer displayed a good adsorption selectivity for di‐(2‐ethylhexyl) phthalate with respect to dibutyl phthalate and di‐n‐octyl phthalate. The reusability of magnetic molecularly imprinted polymer was demonstrated for at least eight repeated cycles without significant loss in adsorption capacity. The adsorption efficiencies of the magnetic molecularly imprinted polymer toward di‐(2‐ethylhexyl) phthalate in real water samples were in the range of 98–100%. These results indicated that the prepared adsorbent could be used as an efficient and cost‐effective material for the removal of di‐(2‐ethylhexyl) phthalate from environmental water samples. 相似文献
We describe a molecularly imprinted polymer (MIP) for the solid-phase extraction of the skin protectant allantoin. The MIP was deposited on the surface of monodisperse silica microspheres possessing acroyl groups on the surface (MH-SiO2). The resulting MIP microspheres (MH-SiO2@MIP) showed a 3.4-fold higher adsorption capacity and a 1.9-fold better selectivity for allantoin than the respective non-imprinted polymer (MH-SiO2@NIP). The monolayer adsorption capacities of the MH-SiO2@MIP and the MH-SiO2@NIP were calculated with the help of the Langmuir model and found to be 6.8 and 1.9 mg?g?1, respectively. Adsorption kinetics fit a pseudo-second order rate mechanism, with an initial adsorption rate of 1.44 for the MH-SiO2@MIP, and of 0.07 mg?g?1?min?1 for the MH-SiO2@NIP. The material can be regenerated, and its adsorption capacity for allantoin remains stable for at least five regeneration cycles. It was successfully used as a sorbent for the selective solid-phase extraction of allantoin from Rhizoma dioscoreae.
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A molecularly imprinted polymer for the selective separation of allantoin was developed. It was successfully used as a sorbent for the selective solid-phase extraction of allantoin from Rhizoma dioscoreae. 相似文献
A novel sensor for the determination of parathion‐methyl based on couple grafting of functional molecular imprinted polymers (MIPs) was fabricated which is developed by anchoring the MIP layer on surfaces of silica particles embedded CdSe quantum dots by surface imprinting technology. The synthesized molecular imprinted silica nanospheres (CdSe@SiO2@MIP) allow a high selectivity and sensitivity of parathion‐methyl via fluorescence intensity decreasing when the MIP material rebinding the parathion‐methyl molecule. Compared with the MIP fabricated in traditional method, the template of parathion‐methyl was easier to remove from the CdSe@SiO2@MIP imprinted material. Under optimal conditions, the fluorescence intensity of parathion‐methyl at the imprinted sensor was detected by spectrofluorophotometer. The relative fluorescence intensity of CdSe@SiO2@MIP decreased linearly with the increasing concentration of parathion‐methyl ranging from 0.013 mg·kg−1 to 2.63 mg·kg−1 with a detection limit (3δ) of 0.004 mg·kg−1 (S/N=3), which is lower than the MIP in tradition. The imprinted film sensor was applied to detect parathion‐methyl in vegetable samples without the interference of other organophosphate pesticides and showed a prosperous application in the field of food safety. 相似文献
Accurate determination of Sarcosine (SAR) in urine with high sensitivity and selectivity is important, because it was recently recommended as a prospective biomarker for prostate cancer (PCa) and significant for the early identification of PCa. In this study, an electrochemical sensor based on Fe3O4 incorporated metal–organic frameworks (MOFs) @molecularly imprinted polymer (MIP) was constructed for SAR detection. Magnetic Fe3O4 nanoparticles embedded zeolitic imidazolate framework-8 (ZIF-8) was used as the support of MIP. MIP provides specific recognition sites for template molecules SAR and MOFs increase the rate of mass transfer and adsorption capacity due to the porous structure. The synthesized super-magnetic Fe3O4@ZIF-8@MIP was self-assembled onto an Au electrode in magnetic field and used as the sensing unit of electrochemical sensor. Cyclic voltammetry was used to monitor the electrochemical behavior, and the binding of SAR resulted in a reduction in the measured current. The results revealed a wide linear range from 1 to 100 pM towards trace SAR determination, with extremely low limit of detection down to 0.4 pM. In conclusion, the Fe3O4@ZIF-8@MIP based sensor provides a selective, sensitive, and convenient method for SAR diagnosis and other cancer marker detection. 相似文献
We describe a molecularly imprinted polymer (MIP) for the solid-phase extraction of the skin protectant allantoin. The MIP was deposited on the surface of monodisperse silica microspheres possessing acroyl groups on the surface (MH-SiO2). The resulting MIP microspheres (MH-SiO2@MIP) showed a 3.4-fold higher adsorption capacity and a 1.9-fold better selectivity for allantoin than the respective non-imprinted polymer (MH-SiO2@NIP). The monolayer adsorption capacities of the MH-SiO2@MIP and the MH-SiO2@NIP were calculated with the help of the Langmuir model and found to be 6.8 and 1.9 mg•g−1, respectively. Adsorption kinetics fit a pseudo-second order rate mechanism, with an initial adsorption rate of 1.44 for the MH-SiO2@MIP, and of 0.07 mg•g−1•min−1 for the MH-SiO2@NIP. The material can be regenerated, and its adsorption capacity for allantoin remains stable for at least five regeneration cycles. It was successfully used as a sorbent for the selective solid-phase extraction of allantoin from Rhizoma dioscoreae.
A molecularly imprinted polymer for the selective separation of allantoin was developed. It was successfully used as a sorbent for the selective solid-phase extraction of allantoin from Rhizoma dioscoreae.
Novel molecularly imprinted polymers of phthalate esters were prepared by atom transfer radical polymerization using methyl methacrylate as functional monomer, cyclohexanone as solvent, cuprous chloride as catalyst, 1‐chlorine‐1‐ethyl benzene as initiator and 2,2‐bipyridyl as cross‐linker in the mixture of methanol and water (1:1, v/v). The effect of reaction conditions such as monomer ratio and template on the adsorption properties was investigated. The optimum condition was obtained by an orthogonal experiment. The obtained polymers were characterized using scanning electron microscopy. The binding property was studied with both static and dynamic methods. Results showed that the polymers exhibited excellent recognition capacity and outstanding selectivity for ten phthalate esters. Factors affecting the extraction efficiency of the molecularly imprinted solid‐phase extraction were systematically investigated. An analytical method based on the molecularly imprinted coupled with gas chromatography and flame ionization detection was successfully developed for the simultaneous determination of ten phthalate esters from edible oil. The method detection limits were 0.10–0.25 μg/mL, and the recoveries of spiked samples were 82.5–101.4% with relative standard deviations of 1.24–5.37% (n = 6). 相似文献