共查询到20条相似文献,搜索用时 15 毫秒
1.
Xinyi Li Xiaolin Cao Zheng Zhang Ziping Zhang Zejun Jiang Jungang Yin 《Journal of separation science》2020,43(11):2133-2141
Molecularly imprinted polymers for strobilurin fungicides were prepared by precipitation polymerization employing azoxystrobin as template molecular together with methacrylic acid monomer and trimethylolpropane triacrylate cross‐linker. Morphological characterization showed molecularly imprinted polymers were uniform spherical particles with about 0.2 μm in diameter, while the morphologies of nonimprinted polymers were irregular bulk. The equilibrium binding and selective experiments proved that molecularly imprinted polymers possessed a higher affinity toward four fungicides compared to nonimprinted polymers and heterogeneous binding sites were found in the molecularly imprinted polymers. Molecularly imprinted solid‐phase extraction conditions, including sample loading solvents, selective washing, and elution solvents, were carefully optimized. The developed method showed good recoveries (70.0–114.0%) with relative standard deviations in range of 1.0–9.8% (n = 3) for samples (cucumber and peach) spiked at three different levels (10, 50, and 100 μg/ kg). The detection limit (signal/noise = 3) ranged from 0.01 to 0.08 μg/kg. The results demonstrated good potential use of this convenient and highly efficient method for determining trace strobilurin fungicides in agricultural products. 相似文献
2.
《Journal of separation science》2018,41(4):958-965
The determination of morphine concentration in the blood and urine is necessary for patients and recruitment purposes. Herein, a magnetic molecularly imprinted polymer for selective and efficient extraction of morphine from biological samples was synthesized by using a core–shell method. Fe3O4 nanoparticles were coated with SiO2‐NH2. The molecularly imprinted polymer was coated on the Fe3O4/SiO2‐NH2 surface by the copolymerization of methacrylic acid and ethylene glycol dimethacrylate in the presence of morphine as the template molecule. The morphological and magnetic properties of the polymer were investigated. Field‐emission scanning electron microscopy indicated that the prepared magnetic polymer is almost uniform. The saturation magnetization values of Fe3O4 nanoparticles, Fe3O4/SiO2‐NH2, and the magnetic polymer were 48.41, 31.69, and 13.02 emu/g, respectively, indicating that all the particles are superparamagnetic. Kinetics of the adsorption of morphine on magnetic polymer were well described by second‐order kinetic and adsorption processes and well fitted by the Langmuir adsorption isotherm, in which the maximum adsorption capacity was calculated as 28.40 mg/g. The recoveries from plasma and urine samples were in the range of 84.9–105.5 and 94.9–102.8%, respectively. By using the magnetic molecularly imprinted polymer, morphine can selectively, reliably, and in low concentration be determined in biological samples with high‐performance liquid chromatography and UV detection. 相似文献
3.
《Journal of separation science》2017,40(2):458-465
The aim of this work was to evaluate the use of a molecularly imprinted polymer as a selective solid‐phase extraction sorbent for the clean‐up and pre‐concentration of patulin from apple‐based food products. Ultra high pressure liquid chromatography coupled to ultraviolet absorbance detection was used for the analysis of patulin. The molecularly imprinted polymer was applied, for the first time, to the determination of patulin in apple juice, puree and jam samples spiked within the maximum levels specified by the European Commission No. 1881/2006. High recoveries (>77%) were obtained. The method was validated and found to be linear in the range 2–100 μg/kg with correlation coefficients greater than 0.965 and repeatability relative standard deviation below 11% in all cases. Compared with dispersive solid‐phase extraction (QuEChERS method) and octadecyl sorbent, the molecularly imprinted polymer showed higher recoveries and selectivity for patulin. The application of Affinisep molecularly imprinted polymer as a selective sorbent material for detection of patulin fulfilled the method performance criteria required by the Commission Regulation No. 401/2006, demonstrating the suitability of the technique for the control of patulin at low ppb levels in different apple‐based foods such as juice, puree and jam samples. 相似文献
4.
Polydopamine‐coated magnetic molecularly imprinted polymer for the selective solid‐phase extraction of cinnamic acid,ferulic acid and caffeic acid from radix scrophulariae sample 下载免费PDF全文
Yuli Yin Liang Yan Zhaohui Zhang Jing Wang Ningjing Luo 《Journal of separation science》2016,39(8):1480-1488
We describe novel cinnamic acid polydopamine‐coated magnetic imprinted polymers for the simultaneous selective extraction of cinnamic acid, ferulic acid and caffeic acid from radix scrophulariae sample. The novel magnetic imprinted polymers were synthesized by surface imprinting polymerization using magnetic multi‐walled carbon nanotubes as the support material, cinnamic acid as the template and dopamine as the functional monomer. The magnetic imprinted polymers were characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and vibrating sample magnetometry. The results revealed that the magnetic imprinted polymers had outstanding magnetic properties, high adsorption capacity, selectivity and fast kinetic binding toward cinnamic acid, ferulic acid and caffeic acid. Coupled with high‐performance liquid chromatography, the extraction conditions of the magnetic imprinted polymers as a magnetic solid‐phase extraction sorbent were investigated in detail. The proposed imprinted magnetic solid phase extraction procedure has been used for the purification and enrichment of cinnamic acid, ferulic acid and caffeic acid successfully from radix scrophulariae extraction sample with recoveries of 92.4–115.0% for cinnamic acid, 89.4–103.0% for ferulic acid and 86.6–96.0% for caffeic acid. 相似文献
5.
Xiaoling Qi Xiaoming Yang Bin Wang Hong Yang 《International journal of environmental analytical chemistry》2013,93(3):268-278
A broad selective molecularly imprinted polymers-based solid phase extraction (MISPE) for levonorgestrel (LNG) from water samples was developed. Using LNG as a template molecule, acrylamide (AA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as linking agent and bulk polymerisation as a synthetic method, the molecularly imprinted polymers (MIPs) were synthesised and characterised. The MIPs displayed a high specific rebinding for LNG with the imprinting factor of 3.71. The Scatchard analysis showed that there was at least one class of binding site for LNG formed in the MIPs with the dissociation constant of 8.046?µg?mL?1. The results of selectivity testing indicated that the MIPs also exhibited high cross-reactivity with structurally related compounds (estrone, methylprednisolone and ethinyl estradiol), but no recognition with non-structurally related compound (indomethacin), suggesting that the MIPs could be used as a broad recognition absorbent. MISPE column was prepared by packing MIPs particles into a common SPE cartridge. The MISPE extraction conditions including loading, washing and eluting solutions were carefully optimised. Water samples spiked with LNG were extracted by MISPE column and detected by high-performance liquid chromatography. The recoveries were found to be 79.97?~?132.79% with relative standard deviations (RSD) of 1.92?~?10.43%, indicating the feasibility of the prepared MIPs for LNG extraction. 相似文献
6.
《Journal of separation science》2018,41(7):1691-1703
Double‐templated molecularly imprinted polymers with specific recognition of three matrine‐type alkaloids were prepared using matrine and oxymatrine as the template molecules. An approach based on double‐templated molecularly imprinted solid‐phase extraction coupled with high‐performance liquid chromatography and tandem mass spectrometry was then developed to extract and purify matrine, oxymatrine, and sophocarpine from Sophora moorcroftiana in the Tibetan plateau herbs. The polymers were characterized by Fourier‐transform infrared spectroscopy and scanning electron microscopy. Their adsorption characteristics were evaluated using adsorption kinetics, isotherms, selectivity, and recycling experiments. This polymer exhibited excellent molecular recognition ability and good selectivity. The obtained polymers as adsorbent was further used for the determination of three matrine‐type alkaloids coupled to high‐performance liquid chromatography with tandem mass spectrometry, the recoveries of three matrines spiked at three concentration levels in samples were 73.25–98.42% (n = 5) with a relative standard deviation less than 6.82%. The limits of detection for the method were 9.23–15.42 μg/kg (S/N = 3). This proposed method was assessed to be an effective method for simultaneous extraction, isolation, and identification of matrine, oxymatrine, and sophocarpine from Sophora moorcroftiana. 相似文献
7.
采用沉淀聚合法,以红霉素(erythromycin,ERY)为模板,甲基丙烯酸(methacrylic acid,MAA)为功能单体,乙二醇二甲基丙烯酸酯(ethyleneglycoldimethacrylate,EGDMA)为交联剂,甲醇/乙腈(1:4,v/v)为致孔剂制备了ERY分子印迹聚合物(molecularly imprinted polymers,MIPs)。通过扫描电镜、平衡吸附实验等对制备的印迹和非印迹聚合物进行表征和测定,结果表明所制备的MIPs对ERY具有特异性吸附作用。Scatchard分析证明MIPs对ERY的吸附存在两类不同结合位点,最大表观结合量(Qmax)和平衡解离常数(Kd)分别为Qmax1=45.24 mg/g,Kd1=0.028 g/L; Qmax2=87.53 mg/g,Kd2=0.20 g/L。以制备的MIPs为吸附剂的分子印迹固相萃取柱,结合高效液相色谱法能够快速检测猪肉样品中的ERY残留,线性范围为0.5~50 mg/L(r2=0.9994),检出限(S/N=3)为0.2 mg/kg。猪肉样品中不同添加水平下ERY的加标回收率为95.2%~104.2%,相对标准偏差(RSD)小于5%。该方法选择性好,灵敏、可靠,可用于猪肉等复杂食品样本中ERY残留的检测。 相似文献
8.
Determination of donepezil in serum samples using molecularly imprinted polymer nanoparticles followed by high‐performance liquid chromatography with ultraviolet detection 下载免费PDF全文
Mehdi Rajabnia Khansari Shahrzad Bikloo Sara Shahreza 《Journal of separation science》2016,39(5):1000-1008
A molecularly imprinted polymer designed for the selective extraction of donepezil from serum samples was synthesized using a noncovalent molecular imprinting approach. The molecularly imprinted polymer was evaluated chromatographically and then its affinity for donepezil was confirmed by solid‐phase extraction. The optimal conditions for solid‐phase extraction were provided by cartridge conditioning using acidified water purified from a Milli‐Q system, sample loading under basic aqueous conditions, clean‐up using acetonitrile, and elution with methanol/tetrahydrofuran. Desirable molecular recognition properties of the molecularly imprinted polymer led to good donepezil recoveries (90–102%). The data indicated that the imprinted polymer has a perfect selectivity and affinity for donepezil and could be used for selective extraction and analysis of donepezil in human serum. 相似文献
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The highly selective, fast and effective sample pretreatment technique molecularly imprinted solid-phase extraction (MISPE) can overcome the low sensitivity of the highly efficient capillary electrophoresis-UV method (CE-UV). In this work, narrowly dispersible bisphenol A (BPA)-imprinted polymeric microspheres with a high capacity factor of k′ = 6.8 and an imprinted factor of I = 6.53 were investigated as selective solid-phase extraction (SPE) sorbents for use in extraction of BPA from different sample matrices (tap water, wastewater, Yangtze River water, soil from the Yangtze River, shrimp and human urine). Washing and eluting protocols of MISPE were optimized. Under optimal conditions, recoveries of MISPE were investigated. Recoveries were basically constant and the relative standard deviation (RSD) was lower than 5.8% when loading volumes changed from 1 to 50 mL. Recoveries ranged from 71.20% to 86.23% for different sample matrices. Compared with C18 SPE, MISPE had higher selectivity and recovery for BPA. BPA was determined with good accuracy and precision in different complex samples using CE-UV coupled with MISPE. Spiked recoveries ranged from 95.20% to 105.40%, and the RSD was less than 7.2%. Because a large loading volume was achieved, the enrichment efficiency of pretreatment and the sensitivity of this method were improved. The limits of detection of this MISPE-CE-UV method for BPA in tap water, wastewater, Yangtze River water, soil from the Yangtze River, shrimp and human urine were 3.0 μg L− 1, 5.4 μg L− 1, 6.9 μg L− 1, 2.1 μg L− 1, 1.8 μg L− 1 and 84 μg L− 1, respectively. 相似文献
11.
报道了一种替米考星磁性表面分子印迹聚合物吸附剂。它以Fe3O4@SiO2为磁性基质,替米考星为模板分子,甲基丙烯酸为功能单体,通过硅烷化反应在Fe3O4@SiO2表面键合上3-(甲基丙烯酰氧)丙基三甲氧基硅烷制备得到。该吸附剂对大环内酯类抗生素表现出高选择性和高富集能力(对4种模型大环内酯的富集倍数为212~675倍)。相比传统的非表面分子印迹聚合物,吸附平衡时间可缩短为30 min,可以重复使用至少6次;结合高效液相色谱-紫外检测,将该吸附剂应用于奶粉中4种大环内酯类抗生素的残留检测,所得检出限和定量限分别为0.58~1.36 μg/kg和1.92~4.55 μg/kg,日内(n=5)和日间(n=3)回收率在83.2%~123.0%之间,RSD均小于12.2%。 相似文献
12.
Nasim Baimani Parviz Aberoomand Azar Syed Waqif Husain Homayon Ahmad Panahi Ali Mehramizi 《Journal of separation science》2019,42(7):1468-1476
We developed an approach for the use of polyester dendrimer during the imprinting process to raise the number of recognized sites in the polymer matrix and improve its identification ability. Photoresponsive molecularly imprinted polymers were synthesized on modified magnetic nanoparticles involving polyester dendrimer which uses the reactivity between allyl glycidyl ether and acrylic acid for the high‐yielding assembly by surface polymerization. The photoresponsive molecularly imprinted polymers were constructed using methylprednisoloneacetate as the template, water‐soluble azobenzene involving 5‐[(4, 3‐(methacryloyloxy) phenyl) diazenyl] dihydroxy aniline as the novel functional monomer, and ethylene glycol dimethacrylate as the cross‐linker. Through the evaluation of a series of features of spectroscopic and nano‐structural, this sorbent showed excellent selective adsorption, recognition for the template, and provided a highly selective and sensitive strategy for determining the methylprednisoloneacetate in real and pharmaceutical samples. In addition, this sorbent according to good photo‐responsive features and specific affinity to methylprednisoloneacetate with high recognition ability, represented higher binding capacity, a more extensive specific area, and faster mass transfer rate than its corresponding surface molecularly imprinted polymer. 相似文献
13.
《Journal of separation science》2018,41(5):1138-1148
A class‐specific macrolide molecularly imprinted polymer was synthesized by precipitation polymerization using tulathromycin as the template and methacrylic acid as the functional monomer. The polymers revealed different specific adsorption and imprinting factor for macrolides with different spatial arrangement of side chains as well as lactonic ring size. And the molecularly imprinted polymer possessed maximum adsorption capacity (54.1 mg/g) and highest imprinting factor (2.4) toward 15‐membered ring azithromycin. On the basis of molecularly imprinted polymer dispersive solid‐phase extraction, a rapid, selective, and reproducible method for simultaneous determination of seven macrolide antibiotics residues in pork was established by using liquid chromatography with tandem mass spectrometry. At spiking levels of 5, 10, 25, and 100 μg/kg, average recoveries of seven macrolides ranged from 68.6 to 95.5% with intraday and interday relative standard deviations below 8%. The limits of detection and limits of quantification were 0.2–0.5 and 0.5–2.0 μg/kg, respectively. 相似文献
14.
Parezhati Pataer Turghun Muhammad Yunusjan Turahun Wenwu Yang Sailemayi Aihebaier Muyasier Wubulikasimu Lingxin Chen 《Journal of separation science》2019,42(8):1634-1643
We describe a stoichiometric approach to the synthesis of molecularly imprinted polymers specific for auramine O. Using the stoichiometric interaction in molecular imprinting, no excess of binding sites is necessary and binding sites are only located inside the imprinted cavities. The free base of the template was obtained to facilitate the interaction with the monomers. Itaconic acid was selected as the functional monomer, and stoichiometric ratio of the interaction with the free base was investigated. The molecularly imprinted polymer preparation conditions such as cross‐linker, molar ratio, porogen were optimized as divinylbenzene, 1:2:20 and chloroform/N,N‐dimethylformamide, respectively. Under the optimum conditions, a good imprinting effect and very high selectivity were achieved. A solid‐phase extraction method was developed using the molecularly imprinted polymers as a sorbent and extraction procedure was optimized. The solid‐phase extraction method showed a high extraction recovery for auramine O in its hydrochloride form and free form compared to its analogues. The results strongly indicated that stoichiometric imprinting is an efficient method for development of high selectivity molecularly imprinted polymers for auramine O. 相似文献
15.
《Journal of separation science》2017,40(6):1396-1402
We aim to develop novel photoresponsive surface molecularly imprinted polymer (SIMP) microspheres, an SiO2‐SIMP, for the photocontrolled extraction of uric acid from biological samples. The SiO2‐SMIP was prepared on silica microspheres by surface polymerization and characterized by using scanning electron microscopy, transmission electron microscopy, FTIR spectroscopy, thermogravimetric analysis, nitrogen adsorption–desorption analysis, and UV‐visible spectroscopy. The SiO2‐SMIP microspheres showed a photocontrolled uptake and release of uric acid in NaH2PO4 buffer upon alternate irradiation at 365 and 440 nm. The SiO2‐SMIP microspheres were able to photocontrollably extract uric acid from complicated biological samples for concentration analysis with no significant interference encountered and it exhibited very good recognition ability and fast binding kinetics toward uric acid. 相似文献
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《Journal of separation science》2017,40(24):4765-4772
New magnetic molecularly imprinted polymers with two templates were fabricated for the recognition of polysaccharides (fucoidan and alginic acid) from seaweed by magnetic solid‐phase extraction, and the materials were modified by seven types of deep eutectic solvents. It was found that the deep eutectic solvents magnetic molecularly imprinted polymers showed stronger recognition and higher recoveries for fucoidan and alginic acid than magnetic molecularly imprinted polymers, and the deep eutectic solvents‐4‐magnetic molecularly imprinted polymers had the best effects. The practical recovery of the two polysaccharides (fucoidan and alginic acid) purified with deep eutectic solvents‐4‐magnetic molecular imprinted polymers in seaweed under the optimal conditions were 89.87, and 92.0%, respectively, and the actual amounts extracted were 20.6 and 18.7 μg/g, respectively. To sum up, the developed method proved to be a novel and promising method for the recognition of complex polysaccharide samples from seaweed. 相似文献
18.
Benito-Peña E Martins S Orellana G Moreno-Bondi MC 《Analytical and bioanalytical chemistry》2009,393(1):235-245
A novel water-compatible molecularly imprinted polymer (MIP), prepared with enrofloxacin (ENR) as the template, has been optimised
for the selective extraction of fluoroquinolone antibiotics in aqueous media. The results of a morphological characterisation
and selectivity tests of the polymer material for ENR and related derivatives are reported. High affinity for the piperazine-based
fluoroquinolones marbofloxacin, ciprofloxacin, norfloxacin and ofloxacin was observed, whereas no retention was found for
nonrelated antibiotics. Various parameters affecting the extraction efficiency of the polymer have been optimised to achieve
selective extraction of the antibiotics from real samples and to reduce nonspecific interactions. These findings resulted
in a MISPE/HPLC-FLD method allowing direct extraction of the analytes from aqueous samples with a selective wash using just
50% (v/v) organic solvent. The method showed excellent recoveries and precision when buffered urine samples fortified at five
concentration levels (25–250 ng mL−1 each) of marbofloxacin, ciprofloxacin, norfloxacin, enrofloxacin and sarafloxacin were tested (53–88%, RSD 1–10%, n = 3). Moreover, the biological matrix of the aqueous samples did not influence the preconcentration efficiency of the fluoroquinolones
on the MIP cartridges; no significant differences were observed between the recovery rates of the antibiotics in buffer and
urine samples. The detection limits of the whole process range between 1.9 and 34 ng mL–1 when 5-mL urine samples are processed. The developed method has been successfully applied to preconcentration of norfloxacin
in urine samples of a medicated patient, demonstrating the ability of the novel MIP for selective extraction of fluoroquinolones
in urine samples. 相似文献
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以吲哚美辛(IDM)为模板分子,丙烯酰胺(AA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,本体聚合法制备过程中加入纳米胶体金,合成了吲哚美辛胶体金分子印迹聚合物(MIPs/Au),利用MIPs/Au表面胶体金对蛋白吸附作用,将抗吲哚美辛的多克隆抗体固定在MIPs/Au上,得到表面固定有抗体的新型聚合物(MIPs/Au-Ab)并对其进行了表征。制备了填充材料为MIPs/Au-Ab的固相萃取柱并对其上样、淋洗和洗脱条件进行了优化,并将所制备的新型萃取柱用于水样中IDM的分离富集。抗吲哚美辛抗体交联在聚合物表面,不仅增加了萃取柱的特异性吸附容量,而且有效地降低了MIP的非特异性吸附。 相似文献