一种聚酰胺胺-苯甲醛树状大分子的合成及其荧光性能

首先以乙二胺为中心核,丙烯酸甲酯为支化单体合成了2.0代的聚酰胺胺树状大分子(PAMAM G 2.0),然后同苯甲醛在60℃水浴恒温反应48 h,得到了一种聚酰胺胺-苯甲醛树状大分子,用FTIR1、HNMR和13CNMR表征了合成产物的分子结构,结果和设计一致。该树状大分子能溶解于三氯甲烷,不溶于水、环己烷。对其荧光性能进行了研究,结果表明,溶液中的Fe3+对聚酰胺胺-苯甲醛树状大分子的荧光具有猝灭效应,并且荧光发射峰从436 nm红移到458 nm;溶液中的Zn2+对聚酰胺胺-苯甲醛树状大分子的荧光具有增强作用,同时荧光发射峰从436 nm蓝移到402 nm。     

间苯氧基苯甲醛修饰聚酰胺胺树状大分子的合成及荧光性能

以乙二胺为中心核,丙烯酸甲酯为支化单体,间苯氧基苯甲醛为端基官能团合成了1.0G和4.0G两种聚酰胺胺-间苯氧基苯甲醛(PAMAM-PBZA)树状大分子,并用FTIR和1HNMR对产物结构进行了表征。通过对其荧光性能的研究表明:溶液中的Ce4+、Zn2+和Cu2+对荧光强度都有较显著的增强作用。另外,随着金属离子和PAMAM-PBZA树状大分子摩尔比的增加,其混合溶液的最大发射峰位置都出现了蓝移现象,尤其是1.0 G PAMAM-PBZA的蓝移现象更加显著。随着PAMAM-PBZA树状大分子浓度的增加,其荧光强度逐渐增强,其中1.0 G产物的荧光发射峰出现了很显著的红移现象。     

新型聚酰胺-胺树状大分子的合成与表征

以1-萘胺为核,乙醇钠为催化剂,与丙烯酸甲酯反应生成0.5代1-萘胺核聚酰胺-胺树状分子,再与乙二胺反应合成了1.0代产物,重复以上两步反应,得4.0代产物。利用核磁共振、傅里叶变换红外光谱仪对产物结构进行表征、分析。对比分析聚酰胺-胺树状大分子与1-萘胺核聚酰胺-胺树状大分子的荧光性能,荧光发射波长从490 nm红移到520 nm。     

苯环为瑞基官能团的疏水型聚酰胺胺树状大分子的合成及性质

以乙二胺为中心核,丙烯酸甲酯为支化单体,苯甲醛为端基官能团,设计合成了一种疏水型的聚酰胺胺树状大分子.随着分子代数的增加,树状大分子在最大吸收波长处的吸收强度增加,而且最大吸收波长出现了红移现象,从248 nm红移到260 nm;树状大分子溶液的荧光强度随着树状大分子的代数增加而增加,同时荧光发射峰从454 nm蓝移到442 nm;产品能溶解于三氯甲烷和二氯甲烷,不溶于水、环己烷和苯.     

树状桥联亚胺基吡啶-2-甲醛配体的合成与红外表征

以乙二胺和丙烯酸甲酯为原料,通过Michael加成和酰胺化缩合反应分别合成了0.5代聚酰胺-胺树状大分子PAMAM-Me和1.0代聚酰胺-胺树状大分子PAMAM-NH2,再利用PAMAM-NH2的端基与吡啶-2-甲醛进行希夫碱反应,制备了一种新型树枝状桥联亚胺基吡啶-2-甲醛配体,产率达到95%以上。作者还讨论了新型配体的合成及分离工艺条件,最后采用红外光谱法对配体的分子结构进行了表征。     

PAMAM树状大分子的合成及除油性能研究

通过发散法合成了各代聚酰胺-胺(PAMAM)树状大分子,整代PAMAM树状大分子合成的最适宜条件为:反应时间24 h,反应温度25℃,n(0.5代PAMAM树状大分子):n(乙二胺)=1:8,溶剂甲醇占总溶液质量分数的20%.用红外光谱对各代产品进行表征,结果证明合成产物是目标分子结构.处理胜利油田孤岛四号联合站污水实验表明,合成的3.0代PAMAM树状大分子除油效果最佳,除油效果好于现场使用的进口药剂罗曼哈斯,在加剂量为70 mg/L时,含油从888.7 mg/L降到132.5 mg/L,除油率可达到85.1%,悬浮物从138 mg/L降到73 mg/L.     

PAMAM树状大分子模板法合成CdSe量子点及其发光性质的研究

以聚酰胺-胺(PAMAM)树状大分子为模板合成了CdSe量子点,X-射线粉末衍射(XRD)分析表明产品与闪锌矿结构的CdSe晶体的标准粉末衍射花样的3个强峰位置相同,透射电镜(TEM)分析显示CdSe量子点包裹在树状大分子孔隙中,分散良好.实验表明以2.5 G和3.5 G PAMAM为模板合成的产品没有检测到荧光发射,而以4.5 G PAMAM树状大分子为模板制备的产品在410～465 nm范围内有较强的荧光发射,其发光波长随反应温度改变.     

多羟基树枝状聚(胺-酯)荧光性能及增溶性研究

以乙二胺、三羟甲基丙烷三丙烯酸酯和3,5-二羟基苯甲酸为原料,合成多羟基树枝状聚(胺-酯)(PAE-3,5-DAC),研究了Sn2+、Fe3+、Cu2+、Co2+、Zn2+对其荧光性能的影响。结果表明,溶液中的Sn2+、Fe3+、Cu2+及Co2+对PAE-3,5-DAC的荧光具有猝灭效应;溶液中的Zn2+对PAE-3,5-DAC的荧光具有先增强后减弱作用。同时测定了PAE-3,5-DAC水溶液对苯甲酸、水杨酸等难溶客体小分子的增溶性,结果表明,在质量浓度相同时,PAE-3,5-DAC对难溶客体小分子的增溶量远高于十二烷基硫酸钠(SDS)。     

PAMAM树状大分子负载和释放阿霉素的耗散粒子动力学模拟

采用耗散粒子动力学模拟方法研究了药物输送载体聚酰胺-胺（PAMAM）树状大分子对抗癌药物阿霉素（DOX）的负载和释放行为。构建了PAMAM树状大分子的粗粒化模型,该模型能准确地重现树状大分子的构象性质。考察了PAMAM树状大分子代数（G）对DOX负载以及pH环境对DOX释放的影响。模拟结果表明,PAMAM树状大分子主要通过疏水作用将DOX包封于内部空腔,G6和G7 PAMAM树状大分子的负载能力较强,因为其孔隙率较高,内部有更多的疏水空腔。在低pH环境下,PAMAM树状大分子结构发生变化,DOX分子能快速地从其中释放,主要原因是PAMAM的伯胺、叔胺和DOX伯胺发生质子化,质子化基团间的静电排斥作用使得PAMAM树状大分子发生溶胀,导致其内部空腔暴露,促进了DOX的释放。本工作可以为基于树状大分子的药物输送体系的设计和优化提供参考。     

PAMAM树状大分子负载和释放阿霉素的耗散粒子动力学模拟

采用耗散粒子动力学模拟方法研究了药物输送载体聚酰胺-胺(PAMAM)树状大分子对抗癌药物阿霉素(DOX)的负载和释放行为。构建了PAMAM树状大分子的粗粒化模型,该模型能准确地重现树状大分子的构象性质。考察了PAMAM树状大分子代数(G)对DOX负载以及pH环境对DOX释放的影响。模拟结果表明,PAMAM树状大分子主要通过疏水作用将DOX包封于内部空腔,G6和G7 PAMAM树状大分子的负载能力较强,因为其孔隙率较高,内部有更多的疏水空腔。在低pH环境下,PAMAM树状大分子结构发生变化,DOX分子能快速地从其中释放,主要原因是PAMAM的伯胺、叔胺和DOX伯胺发生质子化,质子化基团间的静电排斥作用使得PAMAM树状大分子发生溶胀,导致其内部空腔暴露,促进了DOX的释放。本工作可以为基于树状大分子的药物输送体系的设计和优化提供参考。     

Spectroelectrochemical analysis of ion-transfer and adsorption of the PAMAM dendrimer at a polarized liquid|liquid interface

The interfacial behavior of the fourth generation polyamidoamine (G4 PAMAM) dendrimer at a water|1,2-dichloroethane (DCE) interface was studied by cyclic voltammetry and potential modulated fluorescence (PMF) spectroscopy. Irregular voltammetric responses were observed at positively polarized interfaces. The cyclic voltammogram was strongly dependent on pH and on the concentrations of the G4 PAMAM dendrimer and the organic supporting electrolyte. PMF spectroscopy was successfully used to analyze the interfacial mechanism of the dendrimer by adding an anionic porphyrin derivative as a fluorescent probe. The results of the PMF measurements demonstrated that the G4 PAMAM dendrimer was transferred across the interface, a process that was accompanied by an adsorption step at pH 7. In contrast, under alkaline conditions, the adsorption process did not seem to be involved in the interfacial behavior.     

树枝状聚（胺-酯）的功能化及其荧光性能研究

以乙二胺(EDA)、三羟甲基丙烷三丙烯酸酯(TMPTA)和苯甲醛(BZA)为原料,合成了聚(胺-酯)-苯甲醛树枝状大分子(PAE-BZA),产率为60.82%,色谱纯度为65.27%。用IR、1HNMR和13CNMR表征了它的结构;并测定了PAE-BZA的荧光性能;考察了不同浓度PAE-BZA、不同溶剂及n(Sn2+)/n(PAE-BZA)对其荧光性能的影响。结果表明,丙酮为溶剂时,0.5 mmol/L PAE-BZA荧光强度最强;以丙酮、甲醇、DMSO、DMF和乙醇等为溶剂,PAE-BZA在乙醇中的荧光强度最强。随着n(Sn2+)/n(PAE-BZA)增加,PAE-BZA的荧光强度先减弱后增强,且Sn2+与PAE-BZA络合顺序是由外围的N原子逐步向内部的N原子络合。     

Pyridine terminated polyurethane dendrimer/chlorinated butyl rubber nanocomposites with excellent mechanical and damping properties

Due to the special viscoelastic property, traditional rubber with high performance has been widely used in human life and production. However, it is challenging to improve the damping property without sacrificing the extensibility. In this work, a novel type of second-generation polyurethane dendrimer terminated with pyridine (G2-Py) was synthesized by using thiolactone chemistry and subsequently complexed with Zn ions. The structure and morphology of G2-Py were characterized. G2-Py-Zn²⁺ was then mixed with chlorinated butyl rubber (CIIR) by a two-roll mill. A series of CIIR/G2-Py-Zn²⁺ elastomers were obtained through vulcanization. CIIR/G2-Py-Zn²⁺ elastomers could achieve high stretchability (a strain of ~1035%), high mechanical strength (a tensile stress of 7.64 MPa). This was benefitted from the friction between G2-Py and CIIR as well as variety of non-covalent bonds provided by G2-Py-Zn²⁺, which can dissipate energy to further improve the strength and extensibility. The coordination of Zn²⁺-pyridine was confirmed by Fourier transform infrared spectroscopy, stress relaxation and cycle tensile test. To further investigate the morphology and damping properties of the elastomers, scanning electron microscopy and dynamic mechanical analysis were performed. CIIR-5 showed the best damping performance with higher tanδ_max and wider effective damping temperatures. Therefore, this dendrimer modification technology provides wider applications for CIIR elastomers in daily life.     

Highly selective fluorescent chemosensor for Zn2+ derived from inorganic-organic hybrid magnetic core/shell Fe3O4@SiO2 nanoparticles

ABSTRACT: Magnetic nanoparticles with attractive optical properties have been proposed for applications in such areas as separation and magnetic resonance imaging. In this paper, a simple and novel fluorescent sensor of Zn2+ was designed with 3,5-di-tert-butyl-2-hydroxybenzaldehyde [DTH] covalently grafted onto the surface of magnetic core/shell Fe3O4@SiO2 nanoparticles [NPs] (DTH-Fe3O4@SiO2 NPs) using the silanol hydrolysis approach. The DTH-Fe3O4@SiO2 inorganic-organic hybrid material was characterized by transmission electron microscopy, dynamic light scattering, X-ray power diffraction, diffuse reflectance infrared Fourier transform, UV-visible absorption and emission spectrometry. The compound DTH exhibited fluorescence response towards Zn2+ and Mg2+ ions, but the DTH-Fe3O4@SiO2 NPs only effectively recognized Zn2+ ion by significant fluorescent enhancement in the presence of various ions, which is due to the restriction of the N-C rotation of DTH-Fe3O4@SiO2 NPs and the formation of the rigid plane with conjugation when the DTH-Fe3O4@SiO2 is coordinated with Zn2+. Moreover, this DTH-Fe3O4@SiO2 fluorescent chemosensor also displayed superparamagnetic properties, and thus, it can be recycled by magnetic attraction.     

香豆素类荧光增强型Cu2+荧光分子探针

设计合成了含酰肼和亚胺结构的双香豆素类Cu2+荧光分子探针CCu,其结构用1HNMR、IR、HRMS和元素分析进行了表征,并考察了其光谱性能。CCu在常见碱金属离子(K+,Na+)、碱土金属离子(Ca2+,Mg2+)、过渡金属及重金属离子(Cd2+,Ag+,Fe3+,Pb2+,Hg2+,Cr3+,Co2+,Ni2+,Cu2+,Zn2+)中能够专一性地识别Cu2+。滴加Cu2+后引起吸收光谱蓝移38 nm,荧光光谱蓝移17 nm,荧光增强8.2倍,溶液荧光由无色变为蓝色。CCu对pH不敏感具有较低的pKa值(3.32±0.07),可在近中性和弱碱性范围内对Cu2+进行检测。     

荧光性聚酰胺-胺树形分子在潜指纹显现中的应用研究

本文系统研究了不同条件(树形分子代数、浓度、浸泡时间等)下荧光性聚酰胺-胺树形分子(PAMAM)水溶液作为荧光探针对锡纸、透明胶带等基底上油印潜指纹的显现效果.结果发现PAMAM树形分子可以和指纹残留物进行靶向结合.结合到指纹纹线上的该荧光性纳米材料在暗室中365 nm紫外光的激发下发出明亮的蓝色荧光,指印纹线与基底反差大、指纹易于辨认,且操作简单,试剂完全环保无污染.这些结果表明PAMAM水溶液是一种潜在的优良的指纹显现试剂.最后,把PAMAM树形分子水溶液对指纹的显现效果进行量化处理,乳突纹与基底间的灰度对比度达到90%以上.     

Poly(amidoamine) dendrimers with phenyl shells: fluorescence and aggregation behavior

The fluorescence and aggregation behavior of poly(amidoamine) (PAMAM) dendrimers modified with phenyl groups at the periphery (PAMAM-P) were investigated. For comparison, the third generation (G3) PAMAM dendrimer with a shell of positive charge (PAMAM-PA) was also synthesized. PAMAM-P G3, G4 and G5 show dual fluorescence emission due to the fluorescence emission of phenyl ring and its excimer. By increasing the generation number from G2 to G4, the fluorescence intensity of phenyl ring decreases, and the fluorescence of phenyl excimer appears and becomes obvious. The three-dimensional geometry arrangement or dendrimer architecture was found to have a strong effect on their fluorescence behavior. This result is further supported by the solvent effect and model compound studies. The lower generations (PAMAM-P G0 to G3) were self-organized into spherical aggregates. However, no aggregation behavior was observed for the higher generations (>G3). The critical aggregation concentration (CAC) values measured by fluorescence spectroscopy were found to decrease gradually with increasing generation number from G0 to G3.     

1,1-双(1H-苯并咪唑-2-基)-1-十三碳烯的合成及其性能

以邻苯二胺和丙二酸为原料,在3 mol/L盐酸催化下合成双(1H-苯并咪唑-2-基)甲烷中间体,然后与月桂醛通过Knoevenagel缩合反应合成了双苯并咪唑衍生物——1,1-双(1H-苯并咪唑-2-基)-1-十三碳烯。利用元素分析、FTIR和~1HNMR对合成产物的结构进行了表征,考察了常规碱催化剂对目标产物收率的影响,并通过UVVis和荧光光谱(FL)测定了目标化合物的光学性能。结果表明:六氢吡啶催化效果最好,产物收率可达76.33%。目标化合物在243、315和361 nm 3处有紫外吸收峰,可有效覆盖日光紫外线UVA和UVB波段;目标化合物溶液在λem=464.5 nm处有蓝紫色荧光,固体薄膜在λ_(em)=476.5 nm处有蓝紫色荧光,荧光量子产率为0.47。标题化合物荧光增白效果与常用荧光增白剂VBL相当。     

以香豆素为母体的荧光探针的合成、离子识别及拟合计算研究

设计合成了含噻唑和腙结构的香豆素类钴离子荧光探针分子CCo,其结构用1HNMR和13CNMR进行了表征,考察了其光谱性能和电化学性能,并对其结构进行了拟合计算研究。CCo在常见金属离子(Cd2+、Co2+、Na+、Mn2+、Fe3+、Pb2+、Hg2+、Cu2+、Zn2+、Cu+、K+、Mg2+、Ag+、Ni2+、Cr3+)中能够选择性地识别Co2+。滴加Co2+后探针吸收光谱红移60 nm,荧光光谱蓝移75 nm。探针分子溶液在三电极系统及四丁基高氯酸胺作电解质下能用于Hg2+的检测。通过拟合计算进一步验证了探针吸收光谱峰值与实验值一致。