共轭聚合物荧光纳米粒子研究进展

近年来,共轭聚合物荧光纳米粒子因其优异的光学性能,在化学、医学和环境科学等研究领域显示了极其广阔的应用前景.相比于传统无机半导体荧光纳米材料,共轭聚合物荧光纳米粒子具有结构多样性、功能可设计性、生物相容性好等显著优势.本文从共轭聚合物荧光粒子的制备方法、光学性能、表面功能化修饰出发,重点讨论了近年来共轭聚合物纳米粒子作为荧光探针在细胞成像及生物化学检测方面的研究进展,阐述了当前研究的主要发展方向和仍需解决的问题.     

大面积多元化表面等离激元金纳米粒子结构的制备

具有显著表面等离激元共振效应的贵金属纳米粒子因其独特的光电学性质在许多领域表现出了潜在的应用价值. 结合纳米压印技术与自组装技术发展了一种高效的多元化纳米粒子结构的制备方法, 并制备了一种由不同尺寸金纳米粒子构成的周期性表面等离激元纳米粒子结构. 实验结果证明此种方法在大批量制备和结构多元化的控制方面具有独特的优势. 利用不同的表面等离激元纳米粒子结构对不同荧光分子增强效果的差异, 设计了2种具有明显明暗差异的荧光条码, 展示了多重的荧光增强响应.     

荧光碳纳米颗粒:新进展和技术挑战

与其他荧光纳米粒子相比,荧光碳纳米颗粒不仅具有良好的生物相容性和易于表面功能化等优点,还具有发光稳定并可实现上转换荧光发射的特性,所以在生物医药领域有重要的应用价值。本文结合近年来的最新研究成果,综述了金刚石、石墨和非晶等不同结构的荧光碳纳米颗粒的制备方法及其局限性;分析了不同结构碳纳米颗粒的荧光发射特性和在生物技术中应用的优缺点;阐述了荧光碳纳米颗粒在今后研究中需要解决的问题和发展方向。     

金属纳米粒子在手性拆分及手性识别领域中的应用

手性是自然界的本质属性,开发新的快速、高效、灵敏的手性分离分析方法对于对映体的立体选择性合成、手性药物的药理研究、对映体的纯度分析以及环境监测均具有重要意义。金属纳米粒子具有比表面积大、稳定性好和表面易修饰等优点,因而可作为理想的载体用于手性色谱领域;由于导带电子的集体震荡而产生的特殊的表面等离子体共振、荧光和催化性能等,使得金属纳米粒子在光学、电化学等手性传感器方面的应用和理论研究也不断深入。该文对近年来不同类型金属纳米粒子(金纳米粒子、银纳米粒子、量子点、磁性纳米粒子等)在手性分离和手性识别领域的应用现状进行了综述,并对该领域今后的发展进行了展望。     

超顺磁/荧光双功能纳米粒子的合成、表征和生物功能化

通过反相微乳液聚合, 在热解法合成的MnFe2O4纳米粒子表面修饰了一层掺杂有荧光染料(联吡啶钌)的SiO2, 制备了同时具有超顺磁性和荧光特性的双功能纳米粒子. 再通过氨基硅烷的修饰作用, 将该双功能纳米粒子与万古霉素结合, 所得到的生物功能化的纳米粒子表现出很好的对大肠杆菌的识别和磁性分离能力. 本研究制备的超顺磁/荧光双功能纳米粒子具有磁性强、光稳定性高、制备简单、分散性好和尺寸均匀等优点, 可以推断这种新型纳米粒子在生物学、医学和分析化学等领域中将有广阔的应用前景.     

掺杂ZnS纳米粒子的制备及应用

近年来,掺杂ZnS半导体纳米材料作为一类新型发光材料,因其独特的光学特性和在众多领域中的广阔应用前景而成为研究的热点。由于量子尺寸效应,随着纳米粒子粒径减小,掺杂ZnS纳米粒子量子产率增加、带隙能增大,导致吸收光谱和荧光激发光谱发生蓝移,而荧光发射光谱红移。本文详细讨论了影响掺杂ZnS纳米粒子发光性能和量子产率的因素,并综述了掺杂ZnS纳米材料制备及其应用的研究进展。     

氧化石墨烯/金银纳米粒子复合材料的制备及其SERS效应研究

近年来,氧化石墨烯/金银纳米粒子复合材料由于其优异的表面增强拉曼散射（SERS）性能引起了人们极大的关注,在污染物检测、化学传感和癌症诊断等领域具有重要的应用价值。本文综述了氧化石墨烯片层上修饰金银纳米粒子、氧化石墨烯包覆金银纳米粒子、氧化石墨烯附着在金银纳米粒子层三种氧化石墨烯/金银纳米粒子复合材料的制备方法,对其SERS效应进行了详细介绍。SERS研究表明,结合了金银纳米粒子与氧化石墨烯两种材料各自在SERS研究与应用中的优势,氧化石墨烯/金银纳米粒子复合材料的SERS性能比单纯金银纳米粒子更加优异。氧化石墨烯在其中起到了化学增强、分子富集、钝化保护、荧光猝灭的重要作用。氧化石墨烯/金银纳米粒子复合材料在表面增强拉曼光谱中具有广阔的应用前景。     

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。     

磁性纳米粒子在生物传感器中的应用研究进展

磁性纳米粒子是一种新型纳米材料,可应用于各种生物活性物质如蛋白质、DNA等的富集和分离,药物的磁靶向,以及疾病的诊断和治疗等许多领域。由于磁性纳米粒子有着独特的化学和物理性能,已经成功应用到磁控生物传感器、DNA传感器、蛋白质传感器、酶传感器以及其它类型的生物传感器中,并显著提高了生物传感器检测的灵敏度、缩短了生化反应的时间和提高检测的通量,为生物传感器领域开辟了广阔的应用前景。本文概述了磁性纳米粒子在生物传感器中的应用研究进展。     

荧光碳点在分析检测中的研究进展

碳点是一种具有强荧光、低毒性、荧光波长可调、无光闪烁等特性的新型荧光纳米粒子。经过近年来的发展,碳点的制备方法逐渐多样化,合成过程更加快捷、简便;使其在生化传感、环境检测等领域中得到了广泛应用。该文简述了碳点的特性及制备方法,综述了荧光碳点在金属离子、阴离子、有机小分子及生物大分子检测中的研究进展,最后提出了其发展过程存在的问题并对其应用前景进行了展望。     

Photoswitchable Fluorescent Nanoparticles: Preparation,Properties and Applications

This minireview highlights recent advances of research dedicated to photoswitchable fluorescent nanoparticles and their applications. Recently, several strategies have been developed to synthesize nanoparticles with optically switchable emission properties: either fluorescence on/off or dual‐alternating‐color fluorescence photoswitching. The underlying mechanisms of fluorescence photoswitching enable many different types of photoswitchable fluorescent nanoparticles to change fluorescence colors, thus validating the basis of the initial photoswitching design. Among all possible applications, the usage of photoswitchable fluorescent nanoparticles to empower super‐resolution fluorescence imaging and to label biological targets was subsequently reviewed. Finally, we summarize the important areas regarding future research and development on photoswitchable fluorescent nanoparticles.     

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).     

Highly Fluorescent Semiconducting Polymer Dots for Biology and Medicine

In recent years, semiconducting polymer nanoparticles have attracted considerable attention because of their outstanding characteristics as fluorescent probes. These nanoparticles, which primarily consist of π‐conjugated polymers and are called polymer dots (Pdots) when they exhibit small particle size and high brightness, have demonstrated utility in a wide range of applications such as fluorescence imaging and biosensing. In this review, we summarize recent findings of the photophysical properties of Pdots which speak to the merits of these entities as fluorescent labels. This review also highlights the surface functionalization and biomolecular conjugation of Pdots, and their applications in cellular labeling, in vivo imaging, single‐particle tracking, biosensing, and drug delivery. We discuss the relationship between the physical properties and performance, and evaluate the merits and limitations of the Pdot probes for certain imaging tasks and fluorescence assays. We also tackle the current challenges of Pdots and share our perspective on the future directions of the field.     

Fluorescent assemblies: Synergistic of amphiphilic molecules and fluorescent elements

In recent years, fluorescent assemblies based amphiphilic molecules have gained attention as unique and powerful materials for multiple applications that cover sensors, optoelectronics and bioimaging because of amphiphilic molecules self-assembly with outstanding flexibility and diversity spanning assembly structure from micelles, vesicles and nano-assemblies to gels. Weak and noncovalent interactions are important driving force for assemblies. The combination of the structural characteristics of self-assembly and the fluorescent properties of the fluorescent building element render the fluorescent material versatility and their easy-to-tune properties. Amphiphilic molecules can be used as building elements to co-assemble with dye molecules, aggregation-induced emission (AIE) gens, fluorescent nanoparticles and new amphiphilic molecules containing fluorescent groups can also be designed and prepared with self-assembly capability. Concomitantly, the improvement of fluorescence performance including fluorescence intensity, quantum yield, stability and controllability during assembly proved outstanding properties of fluorescence assemblies. These promising fluorescent assemblies are by far not exhaustive in construction method and mechanism explanation but foreshadow their more potential applications. Here, we will understand deeper the fluorescent assemblies and inspire future developments and applications employing this emerging fluorescence soft materials.     

Fluorescent Phthalocyanine-Encapsulated Bovine Serum Albumin Nanoparticles: Their Deployment as Therapeutic Agents in the NIR Region

In recent times, researchers have aimed for new strategies to combat cancer by the implementation of nanotechnologies in biomedical applications. This work focuses on developing protein-based nanoparticles loaded with a newly synthesized NIR emitting and absorbing phthalocyanine dye, with photodynamic and photothermal properties. More precisely, we synthesized highly reproducible bovine serum albumin-based nanoparticles (75% particle yield) through a two-step protocol and successfully encapsulated the NIR active photosensitizer agent, achieving a good loading efficiency of 91%. Making use of molecular docking simulations, we confirm that the NIR photosensitizer is well protected within the nanoparticles, docked in site I of the albumin molecule. Encouraging results were obtained for our nanoparticles towards biomedical use, thanks to their negatively charged surface (−13.6 ± 0.5 mV) and hydrodynamic diameter (25.06 ± 0.62 nm), favorable for benefitting from the enhanced permeability and retention effect; moreover, the MTT viability assay upholds the good biocompatibility of our NIR active nanoparticles. Finally, upon irradiation with an NIR 785 nm laser, the dual phototherapeutic effect of our NIR fluorescent nanoparticles was highlighted by their excellent light-to-heat conversion performance (photothermal conversion efficiency 20%) and good photothermal and size stability, supporting their further implementation as fluorescent therapeutic agents in biomedical applications.     

Preparation and Characterization of Uniform Near IR Polystyrene Nanoparticles

Biomaterials for in vivo fluorescence imaging are required to be biocompatible, nontoxic, photostable and highly fluorescent. Fluorescence must be in the near infrared (NIR) region of the electromagnetic spectrum to avoid absorption and autofluorescence of endogenous tissues. NIR fluorescent polystyrene nanoparticles may be considered ideal biomaterials for in vivo imaging applications. These NIR nanoparticles were prepared by a swelling process of polystyrene template nanoparticles with a hydrophobic NIR dye dissolved in a water‐miscible swelling solvent, a method developed for preparation of nonbiodegradable nanoparticles, for NIR fluorescent bioimaging applications. This method overcomes common problems that occur with dye entrapment during nanoparticle formation such as loss of fluorescence and size polydispersity. Fluorescence intensity of the nanoparticles was found to be size dependent, and was optimized for differently sized nanoparticles. The resulting NIR nanoparticles were also found to be more fluorescent and highly photostable compared to the free dye in solution, showing their potential as biomaterials for in vivo fluorescence imaging.     

One‐pot synthesis of carbon dots@ZrO2 nanoparticles with tunable solid‐state fluorescence

In recent years, fluorescent carbon dots (CDs) have been developed and showed potential applications in biomedical imaging and light‐emitting diodes (LEDs) for their excellent fluorescent properties. However, it still remains a challenge to incorporate fluorescent CDs into the host matrix in situ to overcome their serious self‐quenching. Herein, a one‐pot hydrothermal method is used to prepare nano‐zirconia with CDs (CDs@ZrO₂) nanoparticles. During the reaction, CDs and nano‐zirconia are generated simultaneously and connected with silane coupling agent. The CDs@ZrO₂ nanoparticles exhibit tunable emission wavelength from 450 to 535 nm emission by regulating the content of citric acid in the feed. The quantum yield of the CDs@ZrO₂ is up to 23.8%. Furthermore, the CDs@ZrO₂ nanoparticles with regulable fluorescence emission can be used for the fluorescent material to prepare white LEDs. The prepared LED has significant white light emission with color coordinates of (0.30, 0.37) and its color rendering index (CRI) is 67.1. In summary, we have developed the solid‐state CDs@ZrO₂ nanoparticles with tunable emission by a valuable strategy, that is, one‐pot method, for white LEDs.     

Fluorescent dye-doped silica nanoparticles: new tools for bioapplications

The need to decipher various biological events has led to the elucidation of the molecular mechanisms underlying a number of disease processes. Consequently, the detection and simultaneous monitoring of chemical interactions between biological targets has become indispensable in medical diagnosis, targeted therapeutics, and molecular biology. Multiplexed applications employing nanomaterials, which represent the integration of nanotechnology and biology, have changed the bioanalytical outlook and provided various promising tools. Among these nanomaterials, fluorescent dye-doped silica nanoparticles have demonstrated excellent potential for use in advanced bioanalysis to facilitate deeper understanding of biology and medicine at the molecular level. In particular, silica nanoparticles have been applied to diagnostics and therapeutic applications in cancer and gene/drug delivery. This feature article summarizes recent developments in the synthesis, biocompatibility, and bioapplications of fluorescent dye-doped silica nanoparticles.     

荧光纳米颗粒标记免疫分析*

荧光纳米颗粒标记是目前免疫分析研究中一个新兴的领域。由于荧光纳米颗粒标记可以有效地提高单个识别分子上标记的荧光量（F/P），从而大大提高分析的灵敏度。但是由于在标记和免疫分析过程中具有很多不同于传统荧光染料的特点，需要很多经验的积累，在现阶段限制了其在实际医学诊断中的广泛应用。本文就近年来荧光纳米颗粒标记免疫分析中涉及到的标记方法、免疫模式、影响因素等方面进行了综述。     

纳米粒子在食源性致病菌检测中的应用进展

食品安全事关人民群众的身体健康和生命安全,而食源性致病菌是食品安全的主要影响因素。由食源性致病菌引起的疾病和死亡持续威胁着全球的公共卫生安全。因此,开发快速、准确且灵敏的食源性致病菌检测方法是预防食源性疾病暴发和确保食品安全的关键。常规检测方法费时费力,需要昂贵的设备和专业的人员,应用受限。近年来,随着纳米技术的快速发展,纳米粒子凭借其小尺寸、高比表面积和高反应活性等理化特性成为食源性致病菌检测领域的研究热点。此外,将识别元件修饰于纳米粒子表面并结合新颖的分析技术,能提高检测的特异性和灵敏度。该综述主要总结和比较了磁性纳米粒子、贵金属纳米粒子、荧光纳米粒子和二氧化硅纳米粒子在食源性致病菌检测中的应用,以期为食源性致病菌的快速分析提供思路。