非共价键自组装制备聚对苯撑乙炔/聚丙烯酸水溶性荧光纳米粒子及其光物理行为研究

通过功能化聚对苯撑乙炔(含羟基与氨基)和聚丙烯酸之间的非共价键自组装制备了一系列含共轭聚合物的水溶性荧光纳米粒子, 并进行了相关结构和光学性质表征. 研究表明, 纳米粒子的大小和聚丙烯酸/聚对苯撑乙炔质量比直接相关. 光物理性质研究表明, 形成水溶性纳米粒子后, 疏水的聚苯撑乙炔链在纳米粒子中易于形成π-链间聚集, 其光物理性质与其在薄膜态时相似.     

pH值响应的共轭聚合物纳米粒子的制备、表征与细胞成像研究

共轭聚合物纳米粒子（CPNs）因其高荧光亮度、低毒性、表面易修饰的特性,近年来在生物材料和生物医药领域备受关注。本论文中我们设计、合成了一种新的pH 值响应共轭聚合物（PFPA）,并通过纳米沉淀方法制备了其纳米粒子。动态光散射实验表明PFPA纳米粒子在水中分散性较好,其粒径约为8 nm。 PFPA纳米粒子的最大吸收峰为379 nm,其摩尔吸光系数为2.1×10⁶ L·mol -1·cm -1;另外该纳米粒子的荧光最大发射峰为422 nm,其荧光量子产率为35%。PFPA纳米粒子在汞灯（100瓦）照射下表现出较好的光稳定性,另外MTT实验表明其具有较低的细胞毒性。该纳米粒子具有pH响应的光学特性,并可以用于活细胞成像。PFPA纳米粒子在癌症诊断、药物与基因传递等方面具有潜在的应用价值。     

基于共轭聚合物的纳米粒子用于肿瘤的近红外二区荧光成像及光热治疗

为提高生物组织荧光成像质量以及对肿瘤的高效光热治疗,设计合成了一种新型的窄带隙共轭聚合物(BDT-TTQ),并通过纳米沉积的方式将聚合物制备成水溶性纳米粒子(BDT-TTQ NPs).该共轭聚合物纳米粒子在1000~1200 nm近红外二区范围具有较好的吸收,在1064 nm的激发光下能实现1200~1400 nm的近红外二区荧光成像. BDT-TTQ NPs纳米粒子粒径分布较窄,形貌呈规则的球形且分散均匀,具有好的生物相容性.该纳米粒子既可以在体外实现较高的近红外二区荧光成像穿透深度,又可以实现对小鼠活体血管的高清晰度的近红外二区荧光成像.此外,BDT-TTQ NPs纳米粒子在1064 nm激光下展现出优异的光热转换效率,具有较高的光毒性,对体外的肿瘤细胞以及小鼠的异质瘤具有高的光热杀伤能力.     

三元共聚法制备高亮度近红外二区荧光共轭聚合物纳米粒子及其二区光热治疗应用

为获得同时具有优异的溶解性,高亮度的近红外二区(NIR-Ⅱ,1000～1700 nm)荧光和强的NIR-Ⅱ光热转换能力的共轭聚合物,采用三元共聚策略构建了基于强电子受体和供体的NIR-Ⅱ发射共轭骨架.在此基础上,进一步通过调控电子给体BDT与2TC之间的比例,得到了一系列具有NIR-Ⅱ吸收和优异溶解性的共轭聚合物(BDT-2TC12,BDT-2TC11,BDT-2TC21).这些聚合物在700～1200 nm具有较强的NIR吸收,并在808 nm激光激发下表现出在1000～1400 nm区域内的优异NIR-Ⅱ荧光性能.利用纳米沉积的方法,将目标聚合物BDT-2TC12用两亲性的二硬脂酰磷脂酰乙酰胺-甲氧基聚乙二醇(DSPE-mPEG)进行包覆,制备得到水溶性良好的纳米粒子(BDT-2TC12NPs).该纳米粒子具有良好的稳定性,在808和1064 nm处均有较强的吸收.在1064 nm激光照射下,纳米粒子表现出优异的NIR-Ⅱ光热转换效果,可以实现对肿瘤细胞的光热治疗(PTT).在808 nm的激光激发下,纳米粒子还可以实现对小鼠血管和其他生物组织的高清晰度的NIR-Ⅱ荧光成像(FI).     

粒子-聚合物相互作用与粒子-粒子相互作用对聚合物基纳米复合物力学性能的影响

聚合物基纳米复合物(PNCs)具有比传统高分子材料更加优异的光学、力学、热力学等性能,广泛应用于各个工程领域.而纳米粒子(NPs)对材料性能提高的机理则是当前聚合物纳米复合物领域研究的重要问题,聚合物纳米复合体系相互作用的影响因素众多,至今尚未明确并完整建立复合体系相互作用与性能增强之间的关系.本文总结了近年来关于纳米粒子填充聚合物基体力学性能的研究,从粒子-聚合物相互作用和粒子-粒子相互作用角度阐述了聚合物纳米复合体系力学性能的增强机理,并根据体系中不同的结构关系分别总结了聚合物/未改性纳米粒子复合体系和聚合物/聚合物接枝纳米粒子复合体系中影响力学性能的因素.该部分内容具有重要的理论和实践意义,有助于构建复合体系微观结构与宏观性能之间的关系,进而对微观层面调控PNCs的力学性能提供指导.     

无机纳米晶-共轭聚合物异质结光电池研究进展

无机纳米晶_共轭聚合物固体薄膜太阳能电池是一种以半导体纳米晶作为电子受体、共轭聚合物作为电子给体的新型异质结光电池,近年来已成为国内外研究的热点。本文综述了近几年国际上关于这一领域的研究进展,重点讨论了几种最具潜力的无机半导体纳米晶(CdSe、TiO2、ZnO)共轭聚合物(P3HT、MEHPPV、MDMOPPV)复合太阳能电池,探讨了其光电转化机理并研究了纳米粒子的形貌、共混比例、制备方法和表面改性等对聚合物太阳能电池性能的影响。     

聚合物纳米粒子的结构和性能对胞吞和细胞功能的影响

随着纳米医学的发展,越来越多的聚合物纳米粒子被用作荧光探针和药物或基因的载体,在生物分析、检测以及药物传输和基因治疗等领域得到应用。细胞的胞吞是细胞将细胞外基质、病毒、微组织或纳米粒子运送到细胞内部的一个重要生理过程。研究细胞对纳米粒子的胞吞,有助于从细胞层次上理解生命现象,掌握细胞内治疗的机理。本文综述了近几年来细胞和聚合物纳米粒子之间相互作用的最新研究结果。首先介绍了用于胞吞研究的常用聚合物纳米粒子体系及其功能化方法,尤其是荧光探针的复合与表面修饰。进而介绍了细胞和聚合物纳米粒子之间相互作用的基本过程,包括聚合物纳米粒子在细胞转运过程中的驱动力、细胞内转运过程、在细胞中的分布及其细胞毒性。对影响聚合物纳米微粒胞吞的因素如纳米粒子浓度、共培养时间、纳米粒子性能（形状、粒径、电荷和PEG修饰）、细胞类型和培养条件等进行了总结。最后重点介绍了用于受体介导细胞胞吞的聚合物纳米粒子体系,指出了目前研究工作中的不足及未来发展方向。     

Q-CdS/聚合物纳米复合膜的制备与荧光性能

采用配位化学合成原理 ,分离制备出颗粒尺寸小于 10nm的单分散性的Q态CdS(Q CdS)纳米粒子 ,将Q CdS纳米粒子与聚合物复合成膜 ,制备出一系列Q CdS 聚合物纳米复合膜 .用紫外可见吸收光谱与透射电镜研究了纳米复合膜的量子尺寸效应和分散性 .通过荧光光谱探讨了不同聚合物基体材料和不同Q CdS含量的纳米复合膜的荧光发光性能 .结果表明 ,一方面这种以聚合物为基体的纳米复合膜 ,由于聚合物与Q CdS之间的相互作用 ,使纳米复合膜表现出与单一相组分完全不同的特征荧光发射峰 ;另一方面 ,随着纳米复合膜中Q CdS含量的不断增大 ,纳米复合膜的荧光强度不断增强 ,在一定浓度时达到最大值 .     

利用聚合物自组装实现绿色荧光蛋白生色团的荧光增强

根据绿色荧光蛋白的发光原理,采用聚乙二醇与聚甲基丙烯酸甲酯的两亲性两嵌段聚合物通过自组装包覆生色团的方式,模拟了绿色荧光蛋白发光,考察了组装行为对光学性能的影响,并将其用于细胞成像.通过核磁共振、高分辨质谱、傅里叶变换红外光谱、凝胶渗透色谱、紫外-可见吸收光谱及荧光光谱等表征了生色团分子和聚合物的结构及性能.生色团紫外最大吸收在371 nm,荧光最大发射峰在428 nm.聚合物和生色团进行组装后,其紫外吸收消失,而最大荧光发射峰强度大大增强,且发生了约70 nm的红移,这是因为组装使得生色团的自由旋转受到了限制,且生色团共平面性增加.动态光散射(DLS)和透射电镜(TEM)证明了纳米粒子的结构和尺寸.由于尺寸适合且具有较好的荧光性能,纳米粒子成功应用于细胞成像.这种绿色荧光蛋白生色团的简单自组装方式在生物成像领域具有良好应用前景.     

聚合物纳米光诊疗剂的制备与应用新进展

共轭聚合物纳米颗粒是由π-共轭有机聚合物组成的尺寸在1~100nm范围内的新型有机纳米材料。与传统的有机小分子、半导体量子点和无机纳米材料相比,聚合物纳米颗粒具有光学性质特殊、结构多样、表面易修饰和生物相容性好等优点,因而被广泛应用于生物成像、传感与检测、载药和治疗等领域。本文主要围绕聚合物纳米颗粒的制备方法、性质结构和生物相容性等方面,重点介绍了聚合物纳米颗粒作为光诊疗剂在荧光成像、光声成像,以及光动力和光热治疗领域的研究进展,并对聚合物纳米颗粒的发展前景和未来面临的挑战进行了探讨。     

Controlled syntheses of polythiophene nanoparticles with plain and hollow nanostructures templated from unimolecular micelles

Polythiophene nanoparticles (PTNs), as one of the typical conjugated polymer nanoparticles (CPNs) with novel optical and electronic properties have won extensive attentions, especially their applications in electronics and bioimaging. However, PTNs obtained with traditional methods are usually nonuniform or unstable. Herein, we developed a novel method to prepare uniform and stable PTNs templated from star‐like unimolecular micelles. Cyclodextrin‐cored unimolecular micelles with tailored components were prepared through atom transfer radical polymerization, and PTNs with plain or hollow nanostructures can be obtained via crosslinking the suspended thiophene units in designed domain of unimolecular micelles. The unimolecular micelles and PTNs were characterized via nuclear magnetic resonance, Fourier transform infrared, transmission electron microscopy, atomic force microscopy, dynamic light scattering, ultraviolet–visible, and photoluminescence, indicating that the PTNs exhibit uniform size, controllable surface chemistry, and well‐defined nanostructures. The obtained PTNs have potential applications in optics, electronics, and bioimaging. Also, this provides a new way to synthesize CPNs with tailored sizes, nanostructures, and surface chemistry. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1550–1555     

Polyfluorene based conjugated polymer nanoparticles for two-photon live cell imaging

Two-photon excitation microscopy (2PEM) has been known as a noninvasive and powerful bio-imaging tool for studying living cells, intact tissues and living animals because of their unique advantages such as localized excitation, deep tissue penetration as well as less photo-damage. However, the major limitations that hinder its practical applications in biological systems are low two-photon absorption cross sections of conventional fluorescence probes. Conjugated polymer nanoparticles (CPNs) consisting of highly fluorescent conjugated polymers are promising fluorescent probes for 2PEM due to their unique advantages including large two-photon absorption cross sections, high fluorescence quantum yield, good photo-stability and biocompatibility, facile chemical synthesis, tunable optical properties as well as versatile surface modifications. This account summarizes the recent efforts of our group on development of novel polyfluorene based CPNs as 2PEM contrast agents for live cell imaging.     

纳米四氧化三铁(Fe3O4)的制备和形貌

纳米Fe₃O₄因其特殊的理化性质和在生物医学领域潜在的应用价值而得到广泛研究。本文综述了纳米Fe3O4的制备方法，包括直流电弧等离子体法、热分解方法、沉淀法、水热法、电化学法、微乳液法、溶胶-凝胶法、有机物模板法、回流法等，结合作者在Fe3O4纳米粒子制备方面的最新工作，介绍了Fe3O4纳米粒子的新颖形貌。对纳米级Fe3O4制备研究的发展趋势进行了展望。     

Fluorescent nanoparticles for intracellular sensing: A review

Fluorescent nanoparticles (NPs), including semiconductor NPs (Quantum Dots), metal NPs, silica NPs, polymer NPs, etc., have been a major focus of research and development during the past decade. The fluorescent nanoparticles show unique chemical and optical properties, such as brighter fluorescence, higher photostability and higher biocompatibility, compared to classical fluorescent organic dyes. Moreover, the nanoparticles can also act as multivalent scaffolds for the realization of supramolecular assemblies, since their high surface to volume ratio allow distinct spatial domains to be functionalized, which can provide a versatile synthetic platform for the implementation of different sensing schemes. Their excellent properties make them one of the most useful tools that chemistry has supplied to biomedical research, enabling the intracellular monitoring of many different species for medical and biological purposes. In this review, we focus on the developments and analytical applications of fluorescent nanoparticles in chemical and biological sensing within the intracellular environment. The review also points out the great potential of fluorescent NPs for fluorescence lifetime imaging microscopy (FLIM). Finally, we also give an overview of the current methods for delivering of fluorescent NPs into cells, where critically examine the benefits and liabilities of each strategy.     

Sub-nanometre sized metal clusters: from synthetic challenges to the unique property discoveries

Sub-nanometre sized metal clusters, with dimensions between metal atoms and nanoparticles, have attracted more and more attention due to their unique electronic structures and the subsequent unusual physical and chemical properties. However, the tiny size of the metal clusters brings the difficulty of their synthesis compared to the easier preparation of large nanoparticles. Up to now various synthetic techniques and routes have been successfully applied to the preparation of sub-nanometre clusters. Among the metals, gold clusters, especially the alkanethiolate monolayer protected clusters (MPCs), have been extensively investigated during the past decades. In recent years, silver and copper nanoclusters have also attracted enormous interest mainly due to their excellent photoluminescent properties. Meanwhile, more structural characteristics, particular optical, catalytic, electronic and magnetic properties and the related technical applications of the metal nanoclusters have been discovered in recent years. In this critical review, recent advances in sub-nanometre sized metal clusters (Au, Ag, Cu, etc.) including the synthetic techniques, structural characterizations, novel physical, chemical and optical properties and their potential applications are discussed in detail. We finally give a brief outlook on the future development of metal nanoclusters from the viewpoint of controlled synthesis and their potential applications.     

Chemistry of two-dimensional MXene nanosheets in theranostic nanomedicine

Transition metal carbide,carbonitride and nitride MXenes,as the emerging two-dimensional(2D)nanomaterials,have aroused burgeoning research interest in a broad range of applications ranging from energy conversion to biomedicines attributing to their distinctive planar nanostructure,physiochemical properties and biological effects.They are featured with fascinating electronic,optical,magnetic,mechanical and thermal properties,which exert significant roles in biomedical applications of 2D MXenes.In this review,we briefly summarize the recent research progress of 2D MXenes and highlight their intrinsic chemistry in theranostic nanomedicines,focusing on the synthetic chemistry for MXenes construction,surface chemistry for surface engineering,physiochemical property for theranostic application and biological chemistry for biosafety evaluation.Furthermore,based on the current achieve ments on MXenes,their potential research directio n,critical challenges and future development in biomedicine are also discussed.It is highly expected that 2D MXene-based nanosystems would have a broad application prospect in theranostic biomedicine provided the current facing critical issues and challenges are adequately solved.     

Controlled aggregation in conjugated polymer nanoparticles via organic acid treatments

Understanding and controlling aggregation structures of conjugated polymers (CPs) in aqueous solutions is critical to improving the physical and photophysical properties of CPs for biological applications. Here, we present spectroscopic evidence, including nuclear magnetic resonance (NMR) spectroscopic results, that different organic acid treatment induces different aggregation structures and photophysical properties of CPs in water. Conjugated polymer nanoparticles (CPNs) were fabricated by treating a non-aqueous soluble, primary amine-containing poly(phenylene ethynylene) (PPE-NH(2)) with organic acids followed by dialysis. CPNs formed by acetic acid (AA) treatment (CPN-AAs) exhibit characteristics of loose aggregation with minimal π-π stacking, while CPNs formed by tartaric acid (TA) treatment (CPN-TAs) exhibit a high degree of π-π stacking among PPE-NH(2) chains. The controlled aggregation for a specific application was demonstrated by comparing the fluorescence quenching abilities of the CPN-AAs and the CPN-TAs. A doubled Stern-Volmer constant was obtained from the densely packed CPN-TAs compared to that of the loosely aggregated CPN-AAs.     

基于DNA与上转换纳米颗粒相结合的生物传感与成像研究进展

脱氧核糖核酸(DNA)的分子识别特性与功能使其在生物传感与成像领域得到了广泛应用. 另一方面, 得益于自身独特的光学性质, 镧系元素掺杂的上转换纳米颗粒在生物医学应用中备受关注. 特别地, 二者的有机结合可产生新的性质与功能, 在生物传感与成像领域展现出优势, 推动了该领域的发展. 本文综合评述了基于DNA与上转换纳米颗粒相结合的生物传感与成像技术的研究进展, 重点聚焦于相关方法的分类与设计原理, 简要概述了相关的应用研究, 并对该领域目前存在的挑战与未来的发展前景进行了讨论.     

Electrochemical methods--important means for fabrication of fluorescent nanoparticles

Fluorescent nanoparticles have attracted much attention over the last two decades. Due to the size- and composition-dependent optical and electrical properties, fluorescent nanoparticles have been emphasized in electronic, optical and biomedical applications. Till now, many kinds of methods have been developed to fabricate diverse fluorescent nanoparticles, which include pyrolysis, template synthesis, hydrothermal synthesis, microemulsion, electrochemical methods and so on. Among them, electrochemical methods are favored for relatively good controllability, ease of operation and mild reaction conditions. By adjusting the applied potential, current, components of the electrolyte and other relevant parameters, the fluorescent nanoparticles could be electrochemically manufactured with tunable sizes, compositions and surface structure, which allows for the modification of electronic and optical properties. Therefore, electrochemical methods are regarded as important means in preparing fluorescent nanoparticles. This review focuses on the recent progress in electrochemical fabrications of fluorescent nanoparticles (together with their optical properties and some applications in optoelectronics and biomedicine).