罗丹明B分子印迹聚合物微球的合成及其在固相萃取中的应用

以罗丹明B为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂,采用沉淀聚合法制备了罗丹明B分子印迹聚合物(MIP)微球,并用扫描电子显微镜表征。 采用紫外分光光度法测定了印迹分子罗丹明B与功能单体丙烯酰胺二者之间的结合常数(K=5.303×103 (mol/L)-1)和化学计量比(n=1)。 考察了沉淀剂的种类和用量对聚合物微球的影响。 将分子印迹聚合物微球应用于固相萃取材料自制固相萃取柱,从加标罗丹明B的红椒粉中萃取罗丹明B。 本文优化了固相萃取条件,高效液相色谱检测表明,在一定的萃取条件下,分子印迹聚合物对加标量为0.479 mg/kg的辣椒中罗丹明B的萃取加标回收率可达91.7％～103.5%。     

对硫磷分子印迹聚合物制备及其在水质检测中的应用

为了有效的分离富集水样中有机磷农药,以对硫磷为模板、三羟甲基丙烷三丙烯酸酯为交联剂,采用紫外聚合方法制备了对硫磷分子印迹聚合物(MIP)。利用紫外光谱、红外光谱研究了对硫磷与不同功能单体间作用力及印迹聚合物的结合位点。利用该MIP,建立MIP-固相萃取-气相色谱法测定水中痕量对硫磷,方法的检出限(3S/N)为0.48μg/L,加标回收率为86.2%～115.7%,相对标准偏差(n=6)为3.0%～6.6%。     

克百威分子印迹聚合物的合成及其性能评价

以克百威为模板分子,甲基丙烯酸(MAA)为功能单体,二甲基丙烯酸乙二醇酯(EGDMA)为交联剂,采用沉淀聚合的方法制备了克百威分子印迹聚合物。通过红外光谱分析得到模板和功能单体的最佳配比为n(carbofuran)∶n(MAA)=1∶6。印迹聚合物的红外光谱测定结果表明,聚合物中存在与模板分子相互作用的特征基团;从印迹聚合物的扫描电镜图观察到分子印迹聚合物(MIP)与空白聚合物(NIP)的表面形态不同,可推论MIP存在与模板分子相互识别的结合位点。通过静态平衡结合法研究了模板分子聚合物的吸附能力、结合动力学和选择特性。结果表明,与非印迹聚合物相比,印迹聚合物对克百威具有较强的吸附特性和很好的专一选择性,3h后基本达到最大吸附量。采用固相萃取柱预处理样品,用高效液相色谱法测定自来水中10、50、100mg/L克百威的加标回收率为94%～117%,相对标准偏差(n=3)为2.5%～4.7%。     

齐多夫定替代模板分子印迹聚合物的制备及其在血清样品固相萃取中的应用

制备了齐多夫定(AZT)替代模板分子印迹聚合物(MIP)用于血清样品的前处理。利用计算机模拟选择最佳单体甲基丙烯酸和交联剂二乙烯基苯,用自制的替代模板(AZT酯化物)制备了AZT的MIP。将替代模板MIP作为固相萃取吸附剂,进行固相萃取并优化萃取条件。确定pH 7的KH2PO4缓冲溶液为上样溶剂,2%(V/V)乙腈/pH 7的KH2PO4缓冲溶液为淋洗剂,甲醇/乙酸(9:1,V/V)作为洗脱剂。渗漏实验结果显示齐多夫定MIP的吸附容量为9.10 mg/g,而非分子印迹聚合物(NIP)的吸附容量仅为1.77 mg/g。以AZT酯化物和拉米夫定为结构类似物,进行吸附实验,发现MIP具有高选择性。本文所制备的替代模板分子印迹聚合物在水溶液体系中表现出了很好的识别能力。血清样品经印迹聚合物固相萃取后,用高效液相色谱法测定,发现MIP萃取柱回收率为99.3%,NIP萃取柱仅为13.2%,说明替代模板MIP可用于血清样品中AZT的选择性分离富集,并可以避免模板渗漏。     

对羟基苯甲酸印迹聚合物微粒的制备及其固相萃取应用

以对羟基苯甲酸(p-HBA)为模板分子,丙烯酰胺(AM)为功能单体,乙二醇二甲基丙烯酸酯为交联剂,采用沉淀聚合法在乙腈溶剂中制备了p-HBA印迹聚合物微粒,研究了p-HBA加入量及聚合反应体系的总浓度对印迹聚合物结合性能的影响,采用色谱法对其进行了评价。结果表明,p-HBA的加入量及反应体系的总浓度对结合性能均有影响,当p-HBA加入量为1.0 mmol(与AM物质的量比为1:2)时,在37.5 mL乙腈中制得印迹聚合物P₂对p-HBA具有高的亲和力(k'=4.01)和选择性。将印迹聚合物P₂作为固相萃取填料,研究了分子印迹固相萃取p-HBA的方法,测得2种不同载样模式下p-HBA的柱容量分别为6.91 μg/100 mg和1.93 μg/100 mg,测得天麻样品中p-HBA的加标回收率为76.8%~86.6%(RSD=3.4%~6.2%)(n=3)。结果表明,采用沉淀聚合法以AM为功能单体制备的p-HBA印迹聚合物微粒适宜作为固相萃取填料,可实现天麻样品中p-HBA的选择性分离净化。     

沉淀聚合法制备3-吲哚乙酸印迹聚合物微粒及其固相萃取应用

以3-吲哚乙酸(IAA)为模板分子、丙烯酰胺(AA)为功能单体,采用沉淀聚合法制备了IAA印迹聚合物微粒,研究了致孔剂乙腈的用量及IAA的加入量对印迹聚合物结合性能的影响,采用色谱法对其进行评价。结果表明,当乙腈为37.5 m L,IAA为2 mmol(与AA物质的量比为1∶1)时,制得印迹聚合物P7对IAA的亲和力最大(k=4.24),印迹因子(IF)为14.1,其对IAA展示了最显著的特异识别能力。将P7作为固相萃取柱的填料,研究了分子印迹固相萃取IAA的方法,测得绿豆芽样品的加标回收率为90.6%~92.6%。结果表明,以AA为功能单体沉淀聚合法制备的IAA印迹聚合物颗粒适合作为固相萃取柱填料,可实现实际样品中IAA的选择性分离净化。该文提出的采用适当增大模板分子加入量的方法是制备高亲和力与高选择性印迹聚合物的一条新途径。     

罗丹明B分子印迹固相萃取小柱的研制及应用

研制一种对罗丹明B具有特异性识别性能的分子印迹固相萃取小柱。用沉淀聚合法制备罗丹明B分子印迹聚合物,通过静态平衡吸附实验及固相萃取实验表征其性能,并对市售辣椒样品中的罗丹明B进行测量。罗丹明B模板聚合物的吸附能力明显优于空白聚合物;印迹固相萃取小柱对罗丹明B标准溶液(0.05 mmol/L)一次性萃取率为98.24%,实际样品测量的回收率为90.0%~95.0%,测定结果的相对标准偏差为0.9%~1.7%(n=3)。罗丹明B分子印迹固相萃取小柱选择性好、萃取率高,可应用于食品、化妆品检测等相关领域。     

咖啡因分子印迹固相萃取柱的制备及应用

以咖啡因作为模板分子,α-甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,制备了咖啡因分子印迹聚合物(MIP)。与非印迹聚合物(NIP)相比,MIP对咖啡因具有更高的吸附容量和选择性,MIP和NIP对咖啡因的最大静态吸附量分别为28.1和16.5mg/g,相对选择因子为1.25。以咖啡因分子印迹聚合物为固相萃取填料,结合高效液相色谱(HPLC),建立了茶水中咖啡因浓度及人饮茶后血清中咖啡因浓度的检测方法。考察了洗脱剂种类和用量对咖啡因回收率的影响。当萃取柱依次以2mL水活化,水溶液上样,2mL水淋洗,6mL甲醇-乙酸(9∶1,V/V)洗脱,咖啡因在MIP固相萃取柱上的回收率达到97.5%,而在NIP柱上的回收率仅为54.9%。     

选择性富集分离虎杖中白藜芦醇苷的分子印迹聚合物的制备及分子识别性能研究

以白藜芦醇苷(POL)为模板分子,分别以丙烯酰胺(AM)、4-乙烯基吡啶(4-VP)、甲基丙烯酸羟乙酯(HEMA)、甲基丙烯酸(MAA)为功能单体,二甲基丙烯酸乙二醇酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,采用本体聚合法制备白藜芦醇苷分子印迹聚合物。采用静态平衡结合实验研究了印迹聚合物对模板分子及不同底物的识别性能。结果表明,以丙烯酰胺为功能单体的印迹聚合物(MIP1)对模板分子的识别性能最好,其次是以4-VP为功能单体的聚合物(MIP2),以HEMA为功能单体的聚合物(MIP3)以及以MAA为功能单体的聚合物(MIP4)的分子识别性能较差。表明功能单体与模板分子之间相互作用的强弱对MIP的识别能力有较大的影响。静态平衡结合法以及Scatchard分析法表明,MIP1对模板分子呈现较好的结合能力和选择性,该印迹聚合物中形成了2类不同的结合位点,离解常数分别为7.43×10-5、3.70×10-3mol/L。将MIP1用于虎杖提取物中POL的固相萃取分离,效果良好。     

分子印迹聚合物纤维固相微萃取-高效液相色谱法测定水中痕量2,4-二氯苯酚

利用分子印迹固相微萃取-高效液相色谱法测定了水中痕量的2,4-二氯苯酚(2,4-DCP)。在石英毛细管中,以2,4-DCP为模板分子,甲基丙烯酸(MAA)为功能单体,聚合反应合成了2,4-DCP分子印迹聚合物纤维,考察模板分子的浓度,功能单体与交联剂的比例,聚合反应时间对制备分子印迹聚合物纤维的影响,优化了2,4-DCP的吸附时间对分子印迹聚合物纤维萃取效率的影响。高效液相色谱法测定了萃取后标准样品溶液中2,4-DCP的含量萃取率大于80%,方法的线性范围为10~120μg/L,检出限为2.5μg/L,相关系数(R2)在0.9993~0.9995之间,实测了自来水、湖水和工业废水水样,加标回收率为91.4%~106.0%,相对标准偏差为1.4%~6.6%。     

Molecularly imprinted polymer with high-fidelity binding sites for the selective extraction of barbiturates from human urine

In this paper we describe the synthesis of a molecularly imprinted polymer (MIP) by precipitation polymerisation, with barbital as the template molecule, and the application of the barbital MIP as a molecularly selective sorbent in the solid-phase extraction (SPE) of barbiturates from human urine samples. The MIP was synthesised by precipitation polymerisation using 2,6-bis-acrylamidopyridine as the functional monomer and DVB-80 as the cross-linking agent. The spherical MIP particles produced were 4.2 ± 0.4 μm in diameter; a non-imprinted control polymer (NIP) in bead form was 4.8 ± 0.4 μm (mean±standard deviation) in diameter. The particles were packed into a solid-phase extraction cartridge and employed as a novel sorbent in a molecularly imprinted solid-phase extraction (MISPE) protocol. The MIP showed high selectivity for the template molecule, barbital, a feature which can be ascribed to the high-fidelity binding sites present in the MIP which arose from the use of 2,6-bis-acrylamidopyridine as the functional monomer. However, the MIP also displayed useful cross-selectivity for other barbiturates besides barbital. For real samples, the MIP was applied for the extraction of four barbiturates from human urine. However, due to the high urea concentration in this sample which interfere the proper interaction of barbiturates onto the MIP, a tandem system using a commercially available sorbent was developed.     

Selective trace enrichment of acidic pharmaceuticals in real water and sediment samples based on solid-phase extraction using multi-templates molecularly imprinted polymers

A novel multi-templates molecularly imprinted polymer (MIP), using acidic pharmaceuticals mixture (ibuprofen (IBP), naproxen (NPX), ketoprofen (KEP), diclofenac (DFC), and clofibric acid (CA)) as the template, was prepared as solid-phase extraction (SPE) material for the quantitative enrichment of acidic pharmaceuticals in environmental samples and off-line coupled with liquid chromatography–mass spectrometry (LC/MS/MS). Washing solvent was optimized in terms of kind and volume for removing the matrix constituents nonspecifically adsorbed on the MIP. When 1 L of water sample spiked at 1 μg/L was loaded onto the cartridge, the binding capacity of the MIP cartridge were 48.7 μg/g for KEP, 60.7 μg/g for NPX, 52 μg/g for CA, 61.3 μg/g for DFC and 60.7 μg/g for IBP, respectively, which are higher than those of the commercial single template MIP in organic medium (e.g. toluene) reported in the literature. Recoveries of the five acidic pharmaceuticals extracted from 1 L of real water samples such as lake water and wastewater spiked at 1 μg/L were more than 95%. The recoveries of acidic pharmaceuticals extracted from 10-g sediment sample spiked at the 10 ng/g level were in the range of 77.4–90.6%. To demonstrate the potential of the MIP obtained, a comparison with commercial C18 SPE cartridge was performed. Molecularly imprinted solid-phase extraction (MISPE) cartridge showed higher recoveries than commercial C18 SPE cartridge for acidic pharmaceuticals. These results showed the suitability of the MISPE method for the selective extraction of a group of structurally related compounds such as acidic pharmaceuticals.     

硅胶表面水胺硫磷分子印迹聚合物的制备及其性能

以水胺硫磷为模板分子,甲基丙烯酸（MAA）为功能单体,三羟甲基丙烷三甲基丙烯酸酯（TRIM）为交联剂,采用表面分子印迹技术,以商品化硅胶为基体,合成了对有机磷农药水胺硫磷具有良好选择性的表面分子印迹聚合物（MIP）。 用红外光谱（IR）、扫描电子显微镜（SEM）和元素分析等技术分别对表面印迹聚合物进行了结构表征和表面形态观察;静态吸附平衡实验和Scatchard分析表明,该印迹聚合物中存在着两类不同的结合位点,离解常数分别为4.84×10-3和15.2×10-3 mol/L。与非印迹聚合物相比,MIP对水胺硫磷有较大的特异性吸附能力,其印迹因子为2.73。     

Synthesis of molecularly imprinted polymers for the application of selective clean-up vinblastine from Catharanthus roseus extract

Molecularly imprinted polymers (MIPs) are synthetic tailor-made polymers with high selectivity towards a particular substance (template). An MIP using vinblastine (VLB) as the template molecule was synthesized and characterized. The presence of monomer-template complexes in a non-covalent way was confirmed by UV-vis spectrometry analysis. The polymerization was performed using methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linking agent, and toluene as the porogenic solvent by a thermo-polymerization method. The characterization of the obtained MIP was evaluated by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis. It was observed that the morphology of the MIP was more porous and rough, and the surface area had a significant increase compared with that of the non-imprinted polymer (NIP). This MIP was used as the sorbents of solid-phase extraction (SPE) to assess the selectivity of the MIP after optimization of the SPE protocol. VLB was specifically adsorbed on the MIP cartridge, while to vincristine (VCR), the chemical analog of VLB, almost no selective binding appeared. On the basis of the results, Catharanthus roseus extract was applied to the MIP cartridge for investigating its capability to extract VLB from the plant extract, and the capacity of the MIP cartridge was also evaluated. It was shown that the MIP could effectively enrich VLB from C. roseus extract and the recovery amounted to 93.8%. The solvents dissolving the samples had significant influence on the capacity of the MIP cartridge; it was 750 μg/g in toluene, 625 μg/g in chloroform, and 250 μg/g in methanol.     

Direct determination of ciprofloxacin by mass spectrometry after a two-step solid-phase extraction using a molecularly imprinted polymer

A molecularly imprinted polymer (MIP) has been prepared for the first time with ciprofloxacin (CIPRO) as the template molecule, via a noncovalent synthetic procedure. Prior to its use as a sorbent in SPE, the MIP was evaluated chromatographically to confirm that it was indeed molecularly imprinted. The MIP was then used to extract CIPRO selectively from urine samples by means of a two-step SPE procedure in which a commercial Oasis cartridge and a molecularly imprinted SPE cartridge were combined in series. This approach allowed the matrix compounds present in the samples to be removed effectively. The urine extracts obtained after this two-step SPE procedure was applied were relatively clean compared to the original samples, and this made it possible to inject directly the extracts into a mass spectrometer and thus quantify CIPRO in urine samples at low levels and reduce the time of analysis.     

尼卡地平分子聚合物的制备及识别性能研究

采用分子印迹技术合成了以尼卡地平为模板分子,甲基丙烯酸为功能单体的分子印迹聚合物(MIP).运用平衡结合实验研究了聚合物的吸附特性和选择识别能力.通过Scatchard方程分析,结合位点的离解常数Kd=1.03 mmol·L-1,最大表观结合常数Qmax=18.76 μmol·g-1.结果表明,分子印迹聚合物对尼卡地平呈现出较高的吸附性和选择识别性,对尼卡地平药物的分离富集和检测具有实际临床意义.     

分子印迹聚合物选择性富集长春碱的研究

分子印迹聚合物(MIPs)是近年来发展起来的一种对特定分子(模板分子)具有高度选择性的合成高分子材料.本文以长春碱(VLB)为模板分子,以甲基丙烯酸(MAA)为功能单体、乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,在偶氮二异丁腈(AIBN)的引发下制备了长春碱印迹聚合物(VLB-MIP).采用紫外光谱对VLB与MAA之间形成的模板-功能单体复合物进行了分析,通过扫描电镜(SEM)对制备的VLB-MIP的表面形态进行了表征,并用BET法对MIP表面的孔径进行了测定.结果表明,VLB-MIP与未加模板分子制备的非印迹聚合物(NIP)相比表面多孔、粗糙,比表面积显著增加.以VLB-MIP作为固相萃取(SPE)的吸附剂,对VLB-MIP的选择性进行了评价,VLB-MIP能特异性地吸附VLB,而对VLB的结构类似物长春新碱(VCR)却没有表现出明显的吸附行为.将长春花提取物上样于填充VLB-MIP的SPE柱上,在最优实验条件下,长春花提取物中的VLB能被高效富集.此外,上样溶剂对MIP柱的吸附容量有影响,长春花提取物溶于非极性溶剂甲苯时,MIP的吸附容量最大为750μg/g,其次是氯仿吸附容量为625μg/g,最小的是甲醇为250μg/g.     

Temperature sensitive dopamine-imprinted (N,N-methylene-bis-acrylamide cross-linked) polymer and its potential application to the selective extraction of adrenergic drugs from urine

A temperature sensitive dopamine-imprinted polymer was prepared in 80% aqueous methanol solution by free-radical cross-linking co-polymerisation of methacrylic acid and acrylamide at 60 degrees C in the presence of N,N-methylene-bis-acrylamide as the cross-linker and dopamine hydrochloride as template molecule. The resulting molecularly imprinted polymer (MIP) formed temperature responsive materials, which could be used for the selective separation of appropriate dopamine and adrenergic compounds from a liquid matrix at ambient temperatures. The thermoresponsive MIP exhibited a swelling-deswelling transition in 80% aqueous methanol solution at about 35 degrees C. The capacity of the thermoresponsive MIP to recognise the template molecule when present in aqueous methanol solution changed with temperature, with the highest selectivity found at 35 degrees C. Additionally, binding parameters obtained from Scatchard analyses indicate that increasing temperature resulted in an increased affinity and binding capacity of specific binding sites, but had less effect on non-selective binding sites. Subsequently, the thermoresponsive MIP was tested for its application as a sorbent material, utilisable in the selective solid-phase extraction (SPE) of dopamine and other adrenergic compounds (epinephrine, isoproterenol, salbutamol and serotonin) from urine samples. It was shown that the compounds that were structurally related to dopamine could be removed by elution, while dopamine and serotonin, the analytes of interest, remained strongly adsorbed to the adsorbent during SPE applications. The thermoresponsive MIP displayed different efficiency in clean-up and enrichments using the SPE protocol at different temperatures.     

环丙沙星分子印迹聚合物的合成及识别性能研究

采用分子印迹技术合成了以环丙沙星为印迹分子,以甲基丙烯酸和4-乙烯基吡啶同时为功能单体的分子印迹聚合物。运用平衡结合实验研究了印迹聚合物的吸附特性和选择识别能力。Scatchard分析表明,在所研究的浓度范围内,分子印迹聚合物中形成了两类不同的结合位点。底物选择实验表明,这种聚合物对环丙沙星呈现高的选择结合能力。     

Extraction of crocin from saffron (Crocus sativus) using molecularly imprinted polymer solid‐phase extraction

A new molecularly imprinted polymer for extraction of crocin from saffron stigmas was prepared using gentiobiose (a glycoside moiety in crocin structure) as a template. Crocin binding to gentiobiose imprinted polymer (Gent‐MIP) was studied in comparison with a blank nonimprinted polymer in aqueous media. Affinity of the Gent‐MIP for the crocin was more than the nonimprinted polymer at all concentrations. In Scatchard analysis, the number of binding sites in each gram of polymer (maximum binding sites) and dissociation constant of crocin to binding sites were 18.4 μmol/g polymer and 11.2 μM, respectively. The Gent‐MIP was then used as the sorbent in an SPE method for isolation and purification of crocin from methanolic extract of saffron stigmas. The recovery of crocin, safranal and picrocrocin was determined in washing and elution steps. The Gent‐MIP had significantly higher affinity for crocin than other compounds and enabled selective extraction of crocin with a high recovery (84%) from a complex mixture. The results demonstrated the possibility of using a part of a big molecule in preparing a molecularly imprinted polymer with a good selectivity for the main structure.