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51.
A new sorbent for molecularly imprinted solid-phase extraction (MISPE) to detect cholesterol (CHO) in food matrices able to work in an aqueous media was synthesized. 相似文献
52.
Huiting Zhang Tao Song Fulin Zong Tiechun Chen Canping Pan 《International journal of molecular sciences》2008,9(1):98-106
2-methylphenoxyacetic acid (2-MPA), 2-methyl-4-chlorophenxyacetic acid (MCPA) and 4-chlorophenoxyacetic acid (4-CPA) were imprinted to investigate the cross-selectivities of molecularly imprinted polymers (MIPs). The result indicates that 2-MPA, which is similar in shape, size and functionality with phenoxyacetic herbicides, are suitable to be used as a suitable template to prepare the MIPs for retaining phenoxyacetic herbicides. To study the ion-pair interactions between template molecules and functional monomer 4-vinylpiridine (4-VP), computational molecular modeling was employed. The data indicate that the cross-selectivities of MIPs for phenoxyacetic acid herbicides depend on the binding energies of complexes. 相似文献
53.
A simple imprinted amino-functionalized silica gel material was synthesized by combining a surface molecular imprinting technique with a sol–gel process for solid-phase extraction–high performance liquid chromatography (SPE–HPLC) determination of diethylstilbestrol (DES). Activated silica gel was used as the supporter and non-imprinted silica sorbent was synthesized without the addition of DES using the same procedure as that of DES-imprinted silica sorbent. Compared with non-imprinted polymer particles, the prepared DES-imprinted silica sorbent showed high adsorption capacity, significant selectivity, good site accessibility and fast binding kinetics for DES. The maximum static adsorption capacity of the DES-imprinted and non-imprinted silica sorbent for DES was 62.58 mg g−1 and 19.89 mg g−1, respectively. The relatively selective factor value of this DES-imprinted silica sorbent was 61.7 at the level of 50 mg L−1. And the uptake kinetics was fairly rapid so that the adsorbent equilibrium was achieved within 10 min. Furthermore, the DES-imprinted polymers were used as the sorbent in solid-phase extraction to determine DES in fish samples. The MIP–SPE–HPLC method showed higher selectivity and good recoveries higher than 87.5% (R.S.D. 11.6%). 相似文献
54.
以吲哚-3-乙酸(indole-3-acetic acid,IAA)为模板、甲基丙烯酸为功能单体、乙腈为致孔剂,采用本体聚合法合成了对IAA有特异性识别的吲哚-3-乙酸分子印迹聚合物(IAA-MIP)。红外光谱分析表明,IAA是以氢键形式结合在聚合物的空腔中。等温吸附线及Scatchard分析表明,洗脱模板后的IAA-MIP结合IAA的能力比空白印迹聚合物(NIP)强,且有2种结合方式,其解离常数分别为KD1=1.04×10-6 mol·L-1和KD2=9.23×10-6 mol·L-1,最大表观结合位点分别为Bmax1=0.10μmol·g-1和Bmax2=0.28μmol·g-1。对植物样品的固相萃取实验表明,洗脱模板后的IAA-MIP对IAA具有较强的特异性吸附能力。 相似文献
55.
采用本体聚合法制备三聚氰胺(MEL)与双氰胺(DCD)双模板分子印迹聚合物(MEL/DCD-MIPs),将其作为固相萃取介质,实现了奶粉中MEL与DCD富集与纯化,建立了奶粉中两种物质同时检测的方法。通过热力学、选择性和动态结合试验表明,与单模板分子印迹聚合物相比,双模板分子印迹聚合物由于双模板-功能单体分子间的多位点协同作用而有更好的印迹效应,对MEL和DCD结合能力高于结构类似物三聚氰酸(CYA)。固相萃取试验显示,MEL/DCD-MIPs可以从市售奶粉中选择性地分离、富集MEL与DCD,对MEL与DCD的加样回收率分别为93.1%~100.1%和75.7%~82.5%,RSD均小于5.2%。所制得的MEL/DCD-MIPs可应用于奶粉等食品中氰胺类物质的检测。 相似文献
56.
使用扫描电子显微镜(SEM)、红外图谱(IR)、循环伏安(CV)、差示脉冲循环伏安(DPV)对血红蛋白聚合物膜修饰电极进行了表征。DPV测试表明血红蛋白的浓度和峰电流分别在低浓度和高浓度下均有良好的线性关系,低浓度下满足线性回归方程ip(μA)=13.05-3.58C(μM),相关系数R为-0.9960。检出限为2.7×10-9M,线性范围8.0×10-9~7.1×10-7M;高浓度下满足线性回归方程Ip(μA)=10.56-0.1001C(μM),相关系数R为-0.9957。检出限为5.7×10-7M,线性范围1.7×10-6~1.4×10-5M。可用于构建生物分子印迹的电化学传感器。 相似文献
57.
Minjie Jiang Lisheng Wang Xu Liu Hua Yang Fan Ren Lizhen Gan Weizhe Jiang 《International journal of molecular sciences》2015,16(2):3441-3451
A temperature-sensitive matrine-imprinted polymer was prepared in chloroform by free-radical cross-linking copolymerization of methacrylic acid at 60 °C in the presence of ethylene glycol dimethacrylate as the cross-linker, N-isopropyl acrylamide as the temperature-responsive monomer and matrine as the template molecule. Binding experiments and Scatchard analyses revealed that two classes of binding sites were formed on molecular imprinted polymer (MIP) at 50 °C. Additionally, the thermoresponsive MIP was tested for its application as a sorbent material for the selective separation of matrine from Chinese medicinal plant radix Sophorae tonkinensis. It was shown that the thermoresponsive MIP displayed different efficiency in clean-up and enrichments using the SPE protocol at different temperatures. 相似文献
58.
59.
Semi-covalent imprinting with carbonyl group as sacrificial spacer was employed to synthesize molecularly imprinted polymer (MIP) for phenols. A series of semi-covalently imprinted polymers were prepared by varying the templates and porogens. The MIP with 4-chlorophenyl (4-vinyl)phenyl carbonate as template was proved to be the best one, with ethylene glycol dimethacrylate (EGDMA) as cross-linker, 2,2-azobisisobutyronitrile(AIBN), and chloroform as initiator and porogen, respectively. Under such conditions, the corresponding non-covalently imprinted polymer was fabricated with 4-chlorophenol (4-CP) as template and 4-vinylpyridine (4-VP) as functional monomer. The polymer prepared by semi-covalent imprinting displayed superior selectivity to the non-covalently imprinted polymer for phenols. The peak broadening and tailing had been largely reduced on the column packed with semi-covalently imprinted polymer. Meanwhile, the constant retention for these phenols and the good linearity for phenol and 4-CP augured that the semi-covalently imprinted polymer had the potential application as stationary phase for quantitative determination of phenols. 相似文献
60.