分子模拟辅助设计磁敏型分子印迹聚合物的制备及性能研究

结合计算模拟方法和分子印迹技术,采用电子转移反应生成催化剂进行原子转移自由基聚合方法,以二苯并噻吩(DBT)为目标物,设计并制备了一种新型磁敏型分子印迹聚合物(MMIPs)。运用多种表征方法对MMIPs形貌进行了研究,利用气相色谱法研究了MMIPs的吸附性能。结果表明,MMIPs的比表面积和孔体积分别为104.755和0.115 m2/g;MMIPs的饱和磁化强度为19.45 emu/g。采用静态吸附实验研究了MMIPs的吸附动力学、吸附等温线和特异性识别能力。MMIPs的动力学结合特性符合Elovich动力学方程,在298,308和318 K时,MMIPs的平衡吸附容量分别为31.81,36.27和43.13 mg/g。在不同吸附温度下,MMIPs吸附能力随浓度的变化符合Sips等温模型。选择性识别实验表明,在其它结构类似化合物的存在下,MMIPs对DBT具有选择性吸附能力。     

核-壳型磁性灭草隆分子印迹聚合物的制备及其吸附性能研究

以二氧化硅修饰的四氧化三铁为载体,灭草隆为模板分子,采用表面印迹技术制备了核-壳结构的磁性灭草隆分子印迹聚合物(Fe3O4@SiO2-MIPs)。采用扫描电镜(SEM)和磁强计(VSM)对产物的结构进行了表征。通过静态平衡结合法研究了磁性分子印迹聚合物的吸附能力、选择性。结果表明,与磁性非分子印迹聚合物相比,磁性分子印迹聚合物对灭草隆具有高选择性和高特异性吸附,最大吸附量80μmol g-1;Scatchard分析表明,印迹聚合物存在两类不同的吸附结合位点,Langmuir模型可以很好拟合吸附等温线,其相关系数R2=0.9989。     

多壁碳纳米管表面邻苯二甲酸二(2-乙基)己酯印迹聚合物的制备及其在固相萃取中的应用

以苯基修饰的多壁碳纳米管为载体,邻苯二甲酸二(2-乙基)己酯为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,在碳纳米管表面接枝一层塑化剂邻苯二甲酸二(2-乙基)己酯印迹聚合层.采用红外光谱和扫描电镜对聚合物进行表征和分析.结果表明,在碳纳米管表面成功接枝一层20～30 nm厚的印迹聚合层.采用高效液相色谱研究该印迹聚合物的吸附性能,结果表明,碳纳米管分子印迹聚合物对邻苯二甲酸二(2-乙基)己酯最大吸附量为69.1 μmol/g,达到吸附平衡时间约为60 min.选择性吸附实验表明,与其它结构类似物相比,该印迹复合材料对邻苯二甲酸二(2-乙基)己酯有良好的识别能力.作为固相萃取材料装填于固相萃取柱中,该印迹聚合物能对芒果汁样品中塑化剂进行有效的分离和富集.     

双功能单体法制备磁性葡萄糖分子印迹聚合物及其吸附性能研究

采用表面分子印迹技术,以改性的磁纳米球作为载体,双功能单体分别为刀豆凝集素和3-氨基苯硼酸,交联剂为N,N'-亚甲基双丙烯酰胺,引发剂为过硫酸铵,采用二次接枝法成功合成了双功能单体的磁性葡萄糖分子印迹聚合物(MMIPs).通过多种表征技术:X射线衍射,扫描电子显微镜,红外光谱,振动样品磁强计,热重分析仪对合成的聚合物进行了表征分析.通过吸附动力学、热力学模型对实验数据进行拟合,探究了反应的吸附机理和吸附过程.合成的MMIPs的印迹因子能达到2.93,吸附量为9.112 mg/g.对其类特异性吸附的探索使得合成的聚合物还可应用于富含糖苷类化合物的提取与分离.     

三聚氰胺磁性分子印迹聚合物材料的制备及性能表征

利用溶剂热法通过控制反应时间和温度制得了分散性好和磁性强的Fe3O4,并利用溶胶凝胶法制备得到包覆SiO2的磁性微球(Fe3O4@SiO2)。以三聚氰胺为模板分子,甲基丙烯酸(MAA)为单体,采用本体聚合法制备了磁性分子印迹聚合物(MMIPs)。通过静态吸附实验表明,MMIPs对三聚氰胺的饱和吸附量高达10.22μg/mg,是磁性非印迹聚合物(MNIPs)的1.62倍。粒子扩散模型、Elovich模型和动态吸附实验表明所制得的MMIPs有较好的吸附性能。     

邻苯二甲酸二异辛酯表面印迹聚合物的制备及其固相萃取应用

采用复合二氧化硅微球(H-SiO2)作为载体,以邻苯二甲酸二异辛酯(DIOP)为模板分子,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,制备了邻苯二甲酸二异辛酯表面印迹聚合物(H-SiO2@MIP)。 分别采用扫描电子显微镜和红外光谱对该印迹聚合物进行了观察和表征,结果表明,制备出的印迹聚合物呈球形,印迹壳层厚度为60~70 nm。 采用高效液相色谱技术对该印迹聚合物的吸附性能进行了检测,结果表明,该印迹聚合物对塑化剂DIOP表现出特异性吸附性能,最大吸附容量为50.35 mg/g,DIOP对于邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二乙酯(DEP)的选择因子(β)分别为2.31和2.47。 将该印迹聚合物装填于固相萃取柱中,结合液相色谱检测技术,能对牛奶样品中的塑化剂DIOP进行有效分离、富集和检测。     

高岭土磁性复合材料表面印迹聚合物选择性吸附分离环丙沙星

以氨基改性的磁性高岭土为基质材料,利用电子转移产生催化剂的原子转移自由基聚合法制备磁性高岭土表面印迹聚合物(MMIPs)。通过FTIR、TEM、TGA、XRD和VSM等方法对其物理化学性质进行表征,其比表面积112 m2·g-1,且具有较好的热稳定性、超顺磁性(Ms=13.365 emu·g-1)。吸附性能研究表明,准二级动力学模型能较好地描述MMIPs对环丙沙星(CIP)吸附动力学行为,Langmuir等温模型能较好地拟合MMIPs对CIP的吸附平衡数据,25℃时MMIPs的单分子层吸附容量为89.36 mg·g-1。选择性实验研究表明,MMIPs对CIP具有较好地选择识别性。结合高效液相色谱分析技术,MMIPs已成功应用于鲜鱼样品中痕量CIP的分离、富集和回收,CIP的回收率为92.15%。     

磁性分子印迹聚合物萃取/气相色谱法分离检测薰衣草精油中的樟脑

以樟脑为模板,Fe3O4为磁性粒子,P(St-co-MAA)为功能单体,制备了对樟脑具有特异选择性的磁性分子印迹聚合物微球(MMIPs)及不加模板的磁性非印迹聚合物(MNIPs)。利用X-射线粉末衍射仪、扫描电镜及傅里叶红外光谱仪对樟脑MMIPs的形态及组成进行表征;采用静态平衡吸附评价MMIPs及MNIPs对模板分子的结合性能,并进行动力学研究。结果显示MMIPs对樟脑表现出较好的特异性吸附,Scatchard分析显示MMIPs对樟脑存在两种不同类型的吸附位点。结合樟脑MMIPs和气相色谱技术,对薰衣草精油中樟脑进行富集分离和检测,在所研究浓度范围内,其回收率在67.0%~75.8%之间,RSD<4.5%,方法检出限为3.16μg/m L,实现了薰衣草精油中有害成分樟脑的快速分离与富集。     

氧化石墨烯基异丙隆分子印迹聚合物的制备及其吸附性能研究

以氧化石墨烯为载体,异丙隆为模板分子,采用表面印迹技术制备了分子印迹聚合物。采用透射电子显微镜、拉曼光谱和热重分析仪对该分子印迹聚合物的结构进行了表征,并通过动态平衡结合法研究了该分子印迹聚合物的吸附能力。结果表明:准二级动力学模型很好地拟合了吸附动力学,相关系数(R2)为0.999 7;与非分子印迹聚合物相比,制备的印迹材料表现出高吸附效率和快速的吸附动力学;选择性吸附试验表明该分子印迹聚合物对异丙隆具有选择性和特异性吸附。     

DNOP磁性分子印迹聚合物的制备及其表征

以磁性Fe_3O_4为载体,邻苯二甲酸二正辛酯(DNOP)为模板,α-甲基丙烯酸为单体,乙二醇二乙基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,通过悬浮聚合的方法制备了DNOP磁性分子印迹聚合物。通过红外光谱和扫描电镜等对聚合物的结构和形态进行了表征,结合气相色谱(GC-FID检测器)技术考察了磁性印迹聚合物对DNOP的吸附性能。通过正交实验表明,当反应在70℃、模板:单体:交联剂=1∶6∶30、引发剂占单体和交联剂总质量的2.5%的条件下,该磁性印迹聚合物对DNOP的饱和吸附量为1.82 mg g~(-1)。等温吸附实验表明,该磁性分子印迹聚合物对DNOP有较好的吸附性能。     

Selective recognition of sesamol using molecularly imprinted polymers containing magnetic wollastonite

The magnetic molecularly imprinted polymers (MMIPs) have been synthesized using piperonal molecules as dummy template and magnetic wollastonite composites as support. The resulting composites were applied to selective recognition of sesamol from aqueous solution. MMIPs were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) analysis, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). MMIPs were demonstrated with an imprinted polymer film (90-100 nm) and exhibited magnetic property (M(s) =8.60 emu/g) and thermal stability. The effective average diameter of the Fe(3) O(4) nanoparticles was about 10 nm and the thickness of magnetic film was about 160 nm. Batch mode adsorption studies were carried out to investigate the specific adsorption equilibrium, kinetics and selective recognition. The Langmuir isotherm model was fitted to the equilibrium data better than the Freundlich model, and the kinetic properties were well described by the pseudo-second-order equation. The value of E(a) in this study was 5.35 kJ/mol for MMIPs. In addition, the selective recognition experiments demonstrated that MMIPs have specific recognition ability toward sesamol.     

磁性伊利石表面分子印迹材料的制备及其对环丙沙星识别特性研究

利用溶剂热法制备磁性伊利石(MILT),以乙烯基功能化的磁性伊利石(MILT-MPS)为基质材料,通过表面引发原子转移自由基聚合法在甲醇/水的混合溶液中制备表面分子印迹材料(MMIPs)。通过 FT-IR、TEM、TGA、XRD 和 VSM 等方法对其物理化学性质进行了表征,其比表面积为109.58 m2/ g,且具有热稳定性、超顺磁性(Ms =3.866 emu/ g)。吸附实验研究表明,Langmuir 等温模型能较好地拟合 MMIPs 对 CIP 的吸附平衡数据,25℃时 MMIPs 的单分子层吸附容量为86.58 mg/ g。选择性识别实验表明,MMIPs 对 CIP 具有较好地选择性识别性。结合高效液相色谱分析技术,将所制备的 MMIPs 应用于环境样品中 CIP 的分离富集和分析测定,方法回收率为93.4%~98.3%,检出限达0.01 mg/ L。     

三聚氰胺磁性表面分子印迹聚合物的制备及其在牛奶样品中的应用

以三聚氰胺（MEL）为模板分子、α-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、Fe₃O₄@SiO₂磁性材料为载体,制备得到三聚氰胺磁性表面分子印迹聚合物（MEL-MMIPs）。分别使用透射电镜（TEM）、热重分析（TGA）、傅立叶变换红外光谱（FT-IR）和振动样品磁强计（VSM）对制备的MMIPs进行表征。结果表明,印迹聚合物层成功地在Fe₃O₄@SiO₂磁性材料表面包覆,印迹粒子具有良好的磁学性能。将磁性分子印迹聚合物应用于牛奶中三聚氰胺的富集分离,采用高效液相色谱法（HPLC）检测,结果显示该磁性表面分子印迹聚合物对三聚氰胺有特异性吸附。以制备的MMIPs为吸附剂,建立了一种简单、快速和高选择性测定牛奶中三聚氰胺的方法。     

Magnetic and hydrophilic imprinted particles via ATRP at room temperature for selective separation of sulfamethazine

In this work, a facile route to prepare hydrophilic molecularly imprinted particles with magnetic susceptibility (MMIPs) was first reported via atom transfer radical precipitation polymerization (ATRPP) in a methanol/water solvent at low temperature (298 K), which can be considered as an environment-friendly system. During the process, 2-hydroxyethyl methacrylate and N, N-methylenebisacrylamide monomers were added to improve the hydrophilicity of the polymers. The obtained materials were characterized in detail by X-ray diffraction, transform infrared spectroscopy, thermogravimetric analysis, vibrating sample magnetometer, scanning electron microscopy and transmission electron microscopy, and then used for the selective separation of sulfamethazine (SMZ) from aqueous medium. The images showed Fe₃O₄ nanoparticles that were successfully embedded into the polymer particles with the size ranging from 450 to 650 nm, which exhibited great superparamagnetic susceptivity and high thermal stability. Batch adsorption experiments were performed to determine specific adsorption equilibrium, kinetics, and selective recognition and separation. The effect of the ratio of the double monomers used in the adsorption property was also studied. The equilibrium data of MMIPs toward SMZ was well fitted by the Langmuir isotherm model, and the maximum adsorption capacity estimated was 66.67 μmol g^?1. The adsorption kinetics rapidly achieved equilibrium within 1.0 h and was well described by the pseudo-second-order model. The MMIPs synthesized showed outstanding affinity and selectivity toward SMZ over structurally analogous antibiotics and easily achieved magnetic separation under an external magnetic field. In addition, the adsorption performance of the resulting MMIPs was no obviously decreased at least six repeated cycles.     

Microwave‐assisted preparation of poly(ionic liquids)‐modified polystyrene magnetic nanospheres for phthalate esters extraction from beverages

The fabrication of novel poly(ionic liquids)‐modified polystyrene (PSt) magnetic nanospheres (PILs‐PMNPs) by a one‐pot miniemulsion copolymerization reaction was achieved through an efficient microwave‐assisted synthesis method. The morphology, structure, and magnetic behavior of the as‐prepared magnetic materials were characterized by using transmission electron microscopy, vibrating sample magnetometry, etc. The magnetic materials were utilized as sorbents for the extraction of phthalate esters (PAEs) from beverage samples followed by high‐performance ultrafast liquid chromatography analysis. Significant extraction parameters that could affect the extraction efficiencies were investigated particularly. Under optimum conditions, good linearity was obtained in the concentration range of 0.5–50 (dimethyl phthalate), 0.3–50 (diethyl phthalate), 0.2–50 (butyl benzyl phthalate), and 0.4–50 μg/L (di‐n‐butyl phthalate), with correlation coefficients R ² > 0.9989. Limits of detection were in the range 125–350 pg. The proposed method was successfully applied to determine PAEs from beverage samples with satisfactory recovery ranging from 77.8 to 102.1% and relative standard deviations ranging from 3.7 to 8.4%. Comparisons of extraction efficiency with PSt‐modified MNPs as sorbents were performed. The results demonstrated that PILs‐PMNPs possessed an excellent adsorption capability toward the trace PAE analytes.     

Preparation of magnetic molecularly imprinted polymer nanoparticles by surface imprinting by a sol–gel process for the selective and rapid removal of di‐(2‐ethylhexyl) phthalate from aqueous solution

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.     

Preparation of magnetic molecularly imprinted polymers for separating rutin from Chinese medicinal plants

The preparation of magnetic molecularly imprinted polymers (MMIPs) which can be used for the separation and purification of rutin from Chinese medicinal plants has been proposed. By applying the improved co-precipitation method, magnetic Fe(3)O(4) particles were easily prepared, followed by the modification of TEOS and functionalization with -CH=CH(2). Using functionalized Fe(3)O(4) particles as the magnetic cores, rutin as the template, and acrylamide as the functional monomer, MMIPs were synthesized by surface-imprinted polymerization under the protection of nitrogen gas and successive mechanical stirring at 60 °C for 24 h. Magnetic non-molecularly imprinted polymers (MNIPs) were also prepared with the same synthesis procedure as with MMIPs only without the presence of rutin. Magnetic particles were characterized by FT-IR, XRD, and TG analysis. And the selectivity of MMIPs was also investigated in detail. In addition, the performance of the MMIPs for the adsorption of rutin in the analysis of Chinese medicinal plants was assessed. The mean recoveries were 84.33% (RSD: 3.22%, n = 3) for Saururus chinensis (Lour.) Bail and 85.20% (RSD: 3.58%, n = 3) for Flos Sophorae, respectively, which showed that the prepared MMIPs with many advantages possess the value of practical application.     

新型磁性分子印迹聚合物的制备及其在氟喹诺酮类抗生素检测中的应用

建立了磁性分子印迹聚合物固相萃取与高效液相色谱联用同时检测环境水中4种氟喹诺酮类抗生素的研究方法。分别利用扫描电子显微镜、透射电子显微镜、X-射线衍射、傅里叶红外光谱、振动样品磁强计对合成的磁性分子印迹聚合物进行表征,对影响吸附实验的参数（包括吸附剂用量、吸附和解析时间、洗脱液种类、样品pH值）进行了考察和优化。在最佳的实验条件下,4种氟喹诺酮类抗生素的方法检出限为4.1~21.3 μg/L,方法定量限为13.7~71.0 μg/L,样品加标回收率为70.6%~103.6%。该方法快速、灵敏,能够满足环境水样中氟喹诺酮类抗生素的残留检测要求。     

Preparation of Surface-Imprinted Polymer Magnetic Nanoparticles with Miniemulsion Polymerization for Recognition of Salicylic Acid

Molecular surface-imprinted polymers nanoparticles encapsulating magnetite modified with oleic acid, for recognition of salicylic acid was prepared by three-step miniemulsion polymerization. The important factors including polymerization process, solvents, miniemulsifying approaches, and co-stabilizer have been investigated to obtain magnetic molecular imprinting polymers (MMIPs) nanoparticles (NPs) with high saturation magnetization (Ms), regular morphology, and good monodispersion. The results showed that the amount of magnetite encapsulated in MMIPs NPs was 43.4 wt% and Ms was 33.584 emu/g. Thus, MMIPs NPs could be separated easily within 2 minutes by an external magnetic field. The transmission electron microscope (TEM) showed MMIPs NPs were of regular sphere with core-shell structure, where magnetite NPs were uniformly encapsulated in homogeneous polymer shells. The average diameter of MMIPs NPs was 98 nm with RSD of 6.6%. Good recognition and high loading of target molecule were achieved by MMIPs NPs in batch rebinding tests.