氧化石墨烯/丙酸氯倍他索分子捕获器的制备及性能

以氧化石墨烯修饰聚乙烯滤板为内部支撑体,采用表面分子印迹技术,以丙酸氯倍他索为模板分子,3-氨丙基三乙氧基硅烷为功能单体,正硅酸乙酯为交联剂,在内部支撑体表面进行分子印迹,制备了一种对丙酸氯倍他索具有特异选择吸附能力的分子捕获器。分别采用FTIR、FESEM、EDS、TGA对分子捕获器的结构、形貌、热稳定性进行了表征。并对其吸附性能进行了研究,结果表明,该分子捕获器对丙酸氯倍他索具有较好的结合性能。将该分子捕获器作为固相萃取整体材料,结合高效液相色谱检测,应用于加标化妆品样品中丙酸氯倍他索的选择性富集分离,方法检出限为0.04 mg/L,准确性、精密度良好。分子捕获器可以重复使用4次,具有良好的耐用性。     

克伦特罗分子印迹聚合物吸附性能研究

选用分子印迹技术,以克伦特罗为印迹分子,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,合成克伦特罗分子印迹聚合物,研究其吸附性能。结果表明,与组成相同的非印迹聚合物相比,克伦特罗印迹聚合物有较大的吸附性能,有望在克伦特罗分离分析中作为固相萃取的材料。     

搅拌管内分子印迹固相萃取涂层的制备与吸附性能

将分子印迹技术与搅拌吸附萃取技术结合,在镀镍铁管内壁制备了以雌二醇分子为模板,PA 66为骨架的分子印迹固相萃取涂层,使整个装置具有搅拌和萃取的功能,并探究了其对雌二醇及其结构类似物分子的吸附性能和选择性能。结果表明:该装置对雌二醇的吸附在90 min内可达平衡,吸附率为67.5%,分别是对雌三醇和雌酮吸附率的14和68倍,说明其对雌二醇具有高选择性;该分子印迹层使用50次后,对雌二醇的吸附率仅下降5.3%,说明管内分子印迹固相萃取涂层能保持较长的使用寿命。     

溶胶-凝胶法制备链霉素分子表面印迹聚合物及其性能表征

以四氢呋喃、乙醇和水的混合溶液(体积比6∶1∶1)为分散剂,3-氨基丙基三乙氧基硅烷和苯基三乙氧基硅烷为功能单体,正硅酸乙酯为交联剂,氨水为催化剂,通过溶胶-凝胶法在二氧化硅微球表面制备了分子印迹聚合物。用分子对接的方法初步分析了链霉素与功能单体和交联剂之间的相互作用,验证了它们形成氢键的可能性。活化时间会影响分子印迹微球的形貌。吸附实验表明,分子印迹微球比非印迹聚合物微球对链霉素具有更优越的吸附性能和选择性。     

溶菌酶分子印迹聚乳酸微球的制备及吸附性能

以改性聚乳酸微球(MPLA)为载体,以γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为功能单体,以四乙氧基硅烷为交联剂,采用溶胶凝胶方法制备了表面溶菌酶分子印迹改性聚乳酸微球(LZY-MIP-MPLA),采用红外、扫描电镜和粒径测定等方法对LZY-MIP-MPLA进行了表征,优化了制备条件。详细研究了LZY-MIP-MPLA对溶菌酶的吸附性能,考察了pH和NaCl对吸附性能的影响。结果显示,LZY-MIP-MPLA对溶菌酶的吸附能力明显大于非印迹改性聚乳酸微球(NIP-MPLA),达到吸附平衡的时间为200min左右。Scatchard方程的分析表明,印迹孔穴对模板分子的作用是不完全等价的,即存在两类不同的结合位点。LZY-MIP-MPLA对溶菌酶和牛血清白蛋白的分离因子为10.13,说明其对溶菌酶具有较好的选择吸附性能。     

溶菌酶分子印迹聚乳酸微球的制备及吸附性能

以改性聚乳酸微球(MPLA)为载体,以γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为功能单体,以四乙氧基硅烷为交联剂,采用溶胶凝胶方法制备了表面溶菌酶分子印迹改性聚乳酸微球(LZY-MIP-MPLA),采用红外、扫描电镜和粒径测定等方法对LZY-MIP-MPLA进行了表征,优化了制备条件。详细研究了LZY-MIP-MPLA对溶菌酶的吸附性能,考察了p H和Na Cl对吸附性能的影响。结果显示,LZY-MIP-MPLA对溶菌酶的吸附能力明显大于非印迹改性聚乳酸微球(NIP-MPLA),达到吸附平衡的时间为200 min左右。Scatchard方程的分析表明,印迹孔穴对模板分子的作用是不完全等价的,即存在两类不同的结合位点。LZY-MIP-MPLA对溶菌酶和牛血清白蛋白的分离因子为10.13,说明其对溶菌酶具有较好的选择吸附性能。     

溶胶-凝胶法制备鞣花酸表面分子印迹聚合物

采用溶胶-凝胶方法和表面分子印迹技术，以二氧化硅为载体，鞣花酸为模板分子，3-氨丙基三乙氧基硅烷为功能单体，四乙氧基硅烷为交联剂，在室温下合成鞣花酸分子印迹聚合物(MIPs)。通过扫描电镜表征了MIP的表面形貌。通过静态吸附实验评价了MIP对鞣花酸的吸附行为。结果显示，MIP对鞣花酸可在40 min内达到吸附平衡，印迹因子为2.68，饱和吸附容量可达70 mg/g；与非印迹聚合物相比，MIP对鞣花酸具有高选择性和特异识别性。对吸附数据进行非线性拟合结果显示，MIP对鞣花酸的吸附动力学较好地符合准二级动力学模型，MIP对鞣花酸的吸附等温线较好地符合Langmuir等温方程。另外，该材料在经过5次循环利用之后，对鞣花酸的吸附容量仍能保持在90%以上，表现了较好的重复利用性能。所合成的MIP能够作为一种良好的选择性吸附鞣花酸的功能材料，有望应用于复杂基质中鞣花酸的分离和纯化。     

分子印迹微溶胶的制备及对水中2,4-二氯苯酚的吸附研究

以2,4-二氯苯酚(2,4-DCP)为模板分子,甲基丙烯酰胺为功能单体,三羟甲基丙烷三甲基丙烯酸酯为交联剂,合成了一系列分子印迹聚合物微溶胶(MIPM)。采用紫外光谱法(UV)研究模板与单体间的结合作用,扫描电子显微镜(SEM)表征印迹聚合物的表面形貌。通过平衡吸附试验对MIPM的吸附性能进行评价。结果表明,当以乙腈作为致孔剂,功能单体与模板分子的摩尔比为4:1时,MIPM对2,4-DCP的印迹因子为1.93,最大吸附容量为159.61 mg/g,吸附在150 min左右可达到平衡。将MIPM用作固相萃取(SPE)柱填料,对水样中的2,4-DCP进行富集试验,回收率为96.30%~108.66%。     

糠醛分子印迹聚合物的制备及吸附性能研究

以糠醛为模板分子,采用本体聚合法制备了对糠醛具有高特异吸附性的糠醛分子印迹聚合物。利用扫描电镜和红外光谱对聚合物进行表征分析,并利用动态吸附、静态吸附和选择性吸附实验考察糠醛印迹聚合物的吸附性能。结果表明,所制备的糠醛分子印迹聚合物对糠醛呈现出较好的特异性吸附能力,有望作为固相萃取材料应用于食品中糠醛残留的分离、富集和检测。     

糠醛分子印迹聚合物的制备及吸附性能研究

以糠醛为模板分子,采用本体聚合法制备了对糠醛具有高特异吸附性的糠醛分子印迹聚合物。利用扫描电镜和红外光谱对聚合物进行表征分析,并利用动态吸附、静态吸附和选择性吸附实验考察糠醛印迹聚合物的吸附性能。结果表明,所制备的糠醛分子印迹聚合物对糠醛呈现出较好的特异性吸附能力,有望作为固相萃取材料应用于食品中糠醛残留的分离、富集和检测。     

Caffeine Molecular Imprinted Microgel Spheres by Precipitation Polymerization

Imprinted uniform microgel spheres were prepared by precipitation polymerization. Acetonitrile was used as the dilute solvent with MAA as the monomer, EDMA as the crosslinker and caffeine as the print molecule. Comparison of caffeine adsorption on molecular imprinted and blank microgel spheres was made. Langmuir model was used to fit the adsorption data. It was found that the caffeine imprinted microgel spheres show specific binding sites to the target molecules. A binding study of caffeine on imprinted microgel spheres was made by Scatchard analysis; the dissociation constants (K_D) and the maximum binding capacity were K_D= 1.84×10⁻⁴mol/L,Q _max = 16.98 μmol/g for high affinity binding site and K_D=1.33×l0⁻³ mol/L, Q_max=46.84 μmol/g for lower affinity binding site, respectively This microgel spheres can be useful affinity adsorbents in further applications.     

Preparation of water‐compatible molecularly imprinted polymers for caffeine with a novel ionic liquid as a functional monomer

Water‐compatible molecularly imprinted polymers (MIPs) for caffeine were synthesized in aqueous medium with a new functional monomer, 1‐(α‐methyl acrylate)‐3‐methylimidazolium bromide (1‐MA‐3MI‐Br), which had π–π and hydrogen‐bonding interactions. Caffeine‐imprinted polymers were prepared in suspension polymerization with 1‐MA‐3MI‐Br and methacrylic acid (MAA), which only had hydrogen bonding, as a functional monomer. For the specific binding characteristics of the new functional monomer 1‐MA‐3MI‐Br, the adsorption capacity and relative separation factor (β) of MIPs for caffeine were significantly enhanced. The maximum adsorption capacities of 1‐MA‐3MI‐Br–MIP and MAA–MIP imprinted microspheres for caffeine were 53.80 and 28.90 μmol/g, respectively. Moreover, the relative separation factors were measured by comparison of the separation characteristics under competitive adsorption conditions. The results showed that the β of MAA–MIP for caffeine relative to theophylline was only 1.65; this showed a very poor recognition selectivity for caffeine, but β of 1‐MA‐3MI‐Br–MIP for caffeine with respect to theophylline was remarkably enhanced to 3.19; this showed an excellent recognition selectivity and binding affinity toward caffeine molecules in an aqueous environment. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

氯霉素分子印迹聚合物功能单体筛选及分子识别性能

以氯霉素(CAP)为模板,采用分子动力学和紫外光谱法分析不同功能单体与模板分子间的相互作用情况以辅助筛选单体,并进行实验印证。分子动力学计算出结合能ΔE和紫外光谱最大吸收峰红移程度大小顺序均为甲基丙烯酸(MAA)>丙烯酸(AA)>丙烯酰胺(AM)>甲基丙烯酸甲酯(MMA),且n(MAA):n(CAP)=1:4时MAA与CAP间已有较强的相互作用。由不同功能单体合成的CAP分子印迹聚合物微球(MIPMs)的静态吸附实验表明,在甲醇溶液中,以MAA为功能单体合成的MIPMs对模板CAP的吸附性能最好,饱和吸附量为470.4μmol/g,AA和AM次之,分别为397.5μmol/g和378.3μmol/g,MMA最小,为172.8μmol/g,该结果与分子动力学计算及紫外光谱分析结果相吻合。以MAA为功能单体优化制备MIPMs,SEM显示所得聚合物微球具有良好的单分散性,平均粒径为8.44μm,分散系数为14.2%。最后研究不同用量MAA合成的CAP-MIPMs的分子识别性,实验发现,在各MAA用量下,所得MIPMs对CAP的静态分配系数均高于结构类似物,在n(CAP):n(MAA)=1:4时,其静态分配系数达到111.63 mL/g,CAP与甲砜霉素(TAP)和氟甲砜霉素(FF)间的分离因子分别为4.57和2.78,具有明显的特异识别性。     

喹唑啉分子印迹聚合物微球的吸附特性

以2,4-二氯-6,7-二甲氧基喹唑啉(DCQAL)为模板分子,采用单步溶胀聚合法制备了粒径均匀的分子印迹聚合物微球(M IPM s),并用静态吸附法研究了功能单体、三乙胺及水对M IPM s吸附性能的影响,考察了微球的识别性能。制得的M IPM s主要靠氢键作用吸附与识别模板分子,甲基丙烯酸(MAA)与模板分子间能产生较强的氢键作用,以其为功能单体制得的M IPM s具有较好的吸附与识别性能,其高亲和力与低亲和力结合点的最大表观吸附量分别为17.53μmol/g和117.02μmol/g,以4-氯-6,7-二甲氧基喹唑啉(CQAL)为竞争底物,其分离因子α达1.78。往吸附液中添加三乙胺或少量水会减弱M IPM s的吸附能力。     

不同功能单体制备的S-萘普生印迹聚合物材料的性能

以S-萘普生为模板,分别采用丙烯酰胺(AM)、N-乙烯基吡咯烷酮(NVP)和甲基丙烯酸(MAA)3种功能单体,合成了印迹聚合物P1、P2和P3。用UV和Chem 3D计算模拟,研究了功能单体与模板分子之间的相互作用,经PM3半经验方法计算得到AM、NVP、MAA与模板分子之间的相互作用能分别为-32.06、-21.01和-1.55kJ/mol。平衡结合实验测得当底物浓度为0.1 mmol/L时,P1、P2和P3的吸附量分别为0.360、0.305和0.150μmol;在浓度为0.1~4 mmol/L时,3种分子印迹聚合物对S-萘普生的吸附量大小关系为P1>P2>P3,这与计算出的功能单体与模板分子之间的相互作用能大小关系一致。     

Precipitation polymerization of molecularly imprinted polymers for recognition of melamine molecule

Molecular imprinted polymer microspheres (MIPs) were prepared by precipitation polymerization using melamine as template molecule, methacrylic acid (MAA) as functional monomer, trimethylol‐propane trimethacrylate (TRIM) as crosslinking agent, acetonitrile as solvent and dispersion medium. Release of the template was performed by continuous extraction with methanol containing 10% acetic acid. The microspheres were observed by scanning electron microscopy (SEM). The perfect microspheres were produced when the addition of crosslinker was 7.48 mmol. The binding capacity of MIPs was examined, Q_max = 68.36 μmol g^?1, and the dissociation constant at binding site of MIPs, K_d = 0.761, was estimated. Compared with the performance of conventional imprinted polymer, the imprinted microspheres showed high selectivity in special binding to template molecule. The imprinted microspheres could be used as the stationary phase in HPLC or SPE for selective extraction of melamine in daily products. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

单步溶胀聚合法制备单分散分子印迹聚合物微球

用无皂乳液聚合法制得的微米级聚苯乙烯微球为种球,以N-甲基天门冬氨酸(NMA)为模板分子,通过单步溶胀聚合法在水相中制备了单分散分子印迹聚合物微球(MIPMs)。研究了影响种球溶胀的因素,并对MIPMs的结构进行了表征。实验表明,单步溶胀聚合法能够制得粒径2~3μm、单分散性好的MIPMs,且具有较好的特异吸附性能。Scatchard分析表明,MIPMs在识别NMA过程中存在两类结合位点,计算得到高亲和力的结合位点的离解常数KD1和最大表观结合常数Bmax1分别为0.223 mmol/L和2.12μmol/g,低亲和力的结合位点的离解常数KD2和最大表观结合常数Bmax2分别为5.34 mmol/L和36.42μmol/g。     

A new molecularly imprinted polymer prepared by surface imprinting technique for selective adsorption towards kaempferol

A new molecularly imprinted polymer (KAE-MPS/SiO₂) with high performance for recognizing kaempferol (KAE) was prepared by adopting the surface molecular imprinting technique with silica nanoparticles modified with 3-methacryloxypropyltrimethoxysilane (MPS) as a carrier material, 2-vinylpridine as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. The static adsorption experiments indicated that KAE-MPS/SiO₂ had significantly higher adsorption capacity for KAE than its non-imprinted polymers. Scatchard analysis revealed that two classes of binding sites were formed in KAE-MPS/SiO₂ with dissociation constants of 0.26 and 2.34 μmol/mL, and the maximum apparent binding capacity was 3.33 and 16.16 μmol/g, respectively. The selectivity coefficients of KAE-MPS/SiO₂ for KAE in relation to competition species myricetin and chlorogenic acid were 2.51 and 4.24, respectively, which suggested that KAE-MPS/SiO₂ had high recognition selectivity and binding affinity for the template KAE. Dynamic binding study showed that the KAE-MPS/SiO₂ had good site accessibility and mass transport for KAE. The KAE-MPS/SiO₂ can be reused many times without decreasing their adsorption capacities significantly.     

Direct synthesis of surface molecularly imprinted polymers based on vinyl–SiO2 nanospheres for recognition of bisphenol A

Molecularly imprinted polymers (MIP) with high performance in selectively recognizing bisphenol A (BPA) were prepared by using a novel and facile surface molecular‐imprinting technique. Vinyl‐functionalized, monodispersed silica spheres were synthesized by a one‐step emulsion reaction in aqueous solution. Then, BPA surface molecularly imprinted polymers (SMIP) were prepared by polymerization with 4‐vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. Maximal sorption capacity (Q_max) of the resulting SMIP was up to 600 μmol g^?1, while that of nonimprinted polymers was only 314.68 μmol g^?1. Kinetic binding study showed that sorption capacity reached 70% of Q_max in 20 min and sorption equilibrium at 80 min. SMIP had excellent accessibility and affinity toward BPA, for the selectivity coefficients of SMIP for BPA in respect to phenol, p‐tert‐butylphenol, and o‐phenylphenol were 3.39, 3.35, and 3.02, respectively. The reusage process verified the SMIP owning admirably stable adsorption capacity toward BPA for eight times. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

黄杉素分子印迹聚合物的合成与性能研究

采用本体聚合法以黄杉素(Taxifolin,TAX)为模板分子,2-乙烯基吡啶(2-Vpy)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,制备了黄杉素分子印迹聚合物(TAX-MIP)。通过紫外光谱考察了TAX与2-Vpy的非共价作用,并采用静态和动态结合实验评价了TAX-MIP对底物分子的结合特性。结果表明,TAX与2-Vpy通过静电作用形成主客体配合物,其结合常数和化学配位比分别为K=6.06×10 10(mol/L)-4和n=4;TAX-MIP对TAX存在不同亲和力的两类结合位点,并对TAX显示出很高的选择吸附特性和良好的分子识别性能;TAX-MIP对TAX的吸附符合准二级反应动力学方程。