纳米粒子在生物分析中的应用

纳米粒子探针与传统的有机染料相比有更好的光谱特性和光化学稳定性。本文介绍了3种类型的纳米粒子在生物分析中的应用，并评价了其作为生物荧光探针的发展前景。     

镉系量子点的生物毒性及相应机制

量子点(quantum dots,QDs)由于其优异的荧光特性在生物学和生物医学领域具有广泛的应用,并且在肿瘤的诊断和治疗方面也表现出巨大的潜力,但是随之而来的生物毒性问题近几年备受研究者们的高度关注。本文选取研究最多的Cd系量子点为代表,总结了量子点体外体内生物毒性的一般规律和特点,重点从量子点进入体内途径、内吞进入细胞方式和细胞内发挥功能等方面探讨了其毒性效应的机制。希望以此为发展安全低毒量子点提供指导和建议,促进量子点的临床应用。     

纳米材料在电化学生物传感器及生物电分析领域中的应用

纳米尺度上的生物分析化学是当今国际生物分析领域研究的前沿和热点.该文阐述了纳米粒子在电化学免疫传感器及电化学DNA传感器领域的应用,着重介绍了以纳米材料为载体设计新型的具有生物分子识别和电信号增强作用的纳米标记粒子在构建高灵敏电化学生物传感器以及多组分同时检测中的应用.     

量子点在生物分析及医学诊断中的研究与应用

量子点(quantum dots,QDs)是近年来发展起来的一种优异的新型荧光纳米材料,在生物分析及医学诊断研究中得到了广泛应用,并取得了一系列重要研究成果。本文简介了过去10年中量子点的合成和表面功能性修饰的发展,并重点介绍其在病原体检测、生物芯片、生物分子相互作用、生物传感器、基因沉默、细胞成像、靶向药物传输、光动力学治疗和植物学研究等领域的研究现状。同时,对量子点的应用前景及研究方向进行了评述和展望。     

基于功能纳米材料的灵敏生物传感策略

21世纪的第一个十年被称为＂传感的十载＂.功能纳米材料为灵敏的生物传感器件（包括光学和电生物传感）的制备提供了优秀的平台.这方面的大多数工作主要聚焦于不同纳米材料的生物功能化,例如金属纳米粒子、半导体纳米粒子和碳纳米粒子,功能化方式包括物理吸附、静电结合、特异性识别或共价键合.这些生物功能化纳米材料可以用作催化剂、电导体、光发射剂、载体或示踪剂,以获取被放大的检测信号、稳定的识别探针或生物传感界面.设计的信号放大策略已经极大地促进了不同领域中稳定、特异、具有选择性和灵敏的生物传感器的发展.本文介绍了基于功能纳米材料的一些生物传感新原理和检测新策略,也讨论了纳米材料的生物功能化方法和生物传感在蛋白质的免疫分析、DNA检测、糖分析和细胞传感中的应用.     

纳米材料在电化学生物传感器中的应用

纳米材料因其具有独特的性质,被广泛应用于研制和发展具有超高灵敏度、超高选择性的电化学生物传感器.本文总结了纳米材料在电化学生物传感系统中的主要功能,介绍了近年来国内外基于纳米材料构建的电化学生物传感器的研究进展,并对该领域的发展前景做出了展望.     

量子点在生物检测中的应用

过去十几年里,量子点从材料科学到生命科学、从基础研究到实际应用都开展了广泛的研究。 量子点在生物成像、光治疗、药物/基因转运、太阳能电池等领域均具有广泛的应用。 通过调节量子点的表面性质,实现量子点与细胞相互作用的可控性是一个关键的问题。 伴随着量子点潜在毒性问题的产生,纳米毒性成为纳米材料安全性评估的重要指标,并且受到科学家们的高度关注。 本文综述了量子点的特性、细胞生物学应用及在生物医药领域相关的细胞毒性研究,并展望了量子点的未来发展趋势。     

纳米材料在电化学生物传感器中的应用及纳米仿生界面的构建

对1995～2011年间各种纳米材料,包括金属纳米粒子、量子点纳米材料、碳纳米材料、复合纳米材料等在电化学生物传感器中的应用及纳米仿生界面的构建进行了综述。     

新型碳纳米材料在电化学中的应用

由于碳纳米材料具有良好的力学、电学及化学性能而被人们广泛研究,特别是对于具有大比表面积、高的电导率和良好生物相容性的碳纳米管、碳纳米纤维和石墨烯更是研究的热点。这些新型碳材料具有许多优异的物理和化学特性,被广泛地应用于诸多领域,特别是在电化学领域中显示出其独特的优势。本文主要阐述了碳纳米材料在电化学领域包括生物传感器、超级电容器和燃料电池中的应用。碳纳米材料由于高的比表面积和其较好的生物相容性,在生物电催化反应中起着重要作用,能够提高酶的直接电子传递速率,因而基于碳纳米材料构建的生物传感器灵敏度高、线性范围宽、重复性和稳定性能好。碳纳米材料是超级电容器研究最早和最成熟的一种,由其制备的超级电容器循环稳定性好,再通过和一些赝电容型电极材料复合,可使其比电容得到提高。另外,碳纳米材料作为燃料电池中的催化剂,能够提高燃料电池的能量密度、燃料利用率和抗中毒能力。     

Ⅱ一Ⅵ型量子点制备及其在生物检测中应用研究进展

Ⅱ-Ⅵ型量子点特殊而优良的可见光区荧光性质使得它们在生物识别及检测中具有潜在的应用前景，因而引起人们的广泛关注。本文概述了Ⅱ-Ⅵ型量子点的制备及其在生物检测中应用的研究进展。     

发光碳量子点的合成、性质和应用

基于碳量子点具有良好的水溶性、化学惰性、低毒性、易于功能化和抗光漂白性等优异性能,碳量子点和其它的碳纳米材料（如富勒烯、碳纳米管和石墨烯等）同样引起了研究者广泛的关注。 碳量子点可以通过很多较为廉价的一步法进行大规模的制备,包括化学氧化法、超声法、微波法和激光烧蚀法等。 本文主要介绍了不同碳量子点的合成方法,以及依赖于碳量子点尺寸和波长等性质的发光性能,并且讨论了碳量子点在生物成像、光催化、能量转换/储存、光电子、光限幅和传感器等方面的应用。     

A novel enzyme-mimic nanosensor based on quantum dot-Au nanoparticle@silica mesoporous microsphere for the detection of glucose

QD-Au NP@silica mesoporous microspheres have been fabricated as a novel enzyme-mimic nanosensor. CdTe quantum dots (QDs) were loaded into the core, and Au nanoparticles (NPs) were encapsulated in the outer mesoporous shell. QDs and Au NPs were separated in the different space of the nanosensor, which prevent the potential energy or electron transfer process between QDs and Au NPs. As biomimetic catalyst, Au NPs in the mesoporous silica shell can catalytically oxidize glucose as glucose oxidase (GOx)-mimicking. The resultant hydrogen peroxide can quench the photoluminescence (PL) signal of QDs in the microsphere core. Therefore the nanosensor based on the decrease of the PL intensity of QDs was established for the glucose detection. The linear range for glucose was in the range of 5–200 μM with a detection limit (3σ) of 1.32 μM.     

Recent Applications of Carbon Nanomaterials for microRNA Electrochemical Sensing

MicroRNA (miRNA) is an important tumor marker in the human body, and its early detection has a great influence on the survival rate of patients. Although there are many detection methods for miRNA at present such as northern blotting, real-time quantitative polymerase chain reaction, microarrays, and others, electrochemical biosensors have the advantages of low detection cost, small instrument size, simple operation, non-invasive detection and low consumption of reagents and solvents, and thus they play an important role in the early detection of cancer. In addition, with the development of nanotechnology, nano-biosensors show great potential. The application of various nanomaterials in the development of electrochemical biosensor has greatly improved the detection sensitivity of electrochemical biosensor. Among them, carbon nanomaterials which have unique electrical, optical, physical and chemical properties have attracted increasing attention. In particular, they have a large surface area, good biocompatibility and conductivity. Therefore, carbon nanomaterials combined with electrochemical methods can be used to detect miRNA quickly, easily and sensitively. In this review, we systematically review recent applications of different carbon nanomaterials (carbon nanotubes, graphene and its derivatives, graphitic carbon nitride, carbon dots, graphene quantum dots and other carbon nanomaterials) for miRNA electrochemical detection. In addition, we demonstrate the future prospects of electrochemical biosensors modified by carbon nanomaterials for the detection of miRNAs, and some suggestions for their development in the near future.     

Photophysical Properties of Au‐CdTe Hybrid Nanostructures of Varying Sizes and Shapes

We design well‐defined metal‐semiconductor nanostructures using thiol‐functionalized CdTe quantum dots (QDs)/quantum rods (QRs) with bovine serum albumin (BSA) protein‐conjugated Au nanoparticles (NPs)/nanorods (NRs) in aqueous solution. The main focus of this article is to address the impacts of size and shape on the photophysical properties, including radiative and nonradiative decay processes and energy transfers, of Au‐CdTe hybrid nanostructures. The red shifting of the plasmonic band and the strong photoluminescence (PL) quenching reveal a strong interaction between plasmons and excitons in these Au‐CdTe hybrid nanostructures. The PL quenching of CdTe QDs varies from 40 to 86 % by changing the size and shape of the Au NPs. The radiative as well as the nonradiative decay rates of the CdTe QDs/QRs are found to be affected in the presence of both Au NPs and NRs. A significant change in the nonradiative decay rate from 4.72×10⁶ to 3.92×10¹⁰ s^?1 is obtained for Au NR‐conjugated CdTe QDs. It is seen that the sizes and shapes of the Au NPs have a pronounced effect on the distance‐dependent energy transfer. Such metal‐semiconductor hybrid nanostructures should have great potentials for nonlinear optical properties, photovoltaic devices, and chemical sensors.     

利用DNA折纸术构建功能纳米材料

DNA折纸术(DNA origami)作为一种精确高效的自组装技术,自2006年Rothemund发明以来在生物医药、高灵敏度检测、纳米光电子器件、等离子体光子学等领域展现出巨大的应用潜力,近年来受到广大研究者的高度关注。 利用DNA折纸术构建纳米材料是以DNA origami结构为载体,通过碱基互补配对的原则及三维结构上可程序化设计和可寻址的特点精确地组装很多功能基团如金属及半导体纳米颗粒,蛋白质和单壁碳纳米管等,并应用于研究无标记的RNA杂交检测、单分子的化学反应、检测间距对多价态的配位体-蛋白质之间键合的影响等。本文对近几年来DNA origami构建功能纳米材料的研究进展加以系统综述,并对DNA origami的发展方向和应用前景进行了展望。     

二维纳米材料的改性及其环境污染物治理方面的应用

二维纳米材料是一类具有类似二维平面形态,且厚度在纳米级甚至数个原子层的材料,其种类繁多并且具有很多与体相材料不同的物化性质,在众多领域受到了广泛关注。二维纳米材料在催化降解、吸脱附、过滤、传感检测等领域具有可观的应用潜力,还可用于环境污染的防治。通过形貌、元素、基团、缺陷的修饰、改性和材料合成等策略可以调控二维纳米材料的性质,从而研发新的材料体系或者改善二维纳米材料的性能。本文首先归纳了二维纳米材料的种类,并重点阐述了各种改性策略的作用及研究现状,以及改性的二维纳米材料在治理水体污染、大气污染和污染物检测等方面的应用,为二维纳米材料在环境治理领域的发展现状作了系统介绍和展望。     

Optimization and performance evaluation of a fluorescent sensor for residual sulfonamide antibiotics in honey samples

In the quest to address the mounting concerns over sulfonamide antibiotic residues in food, which pose significant threats to public health and food safety, this study introduces a cutting-edge detection method. Surface molecular imprinting on silicon nanoparticles is harnessed to fabricate a novel fluorescent sensor that exploits the luminescent properties of cadmium telluride (CdTe) quantum dots. This innovative approach aims to detect residual sulfonamide antibiotics with high specificity and sensitivity. At the heart of this research is the development of a core-shell nanostructure, where silicon dioxide serves as the core, and a molecularly imprinted polymers (MIPs) layer, tailored to recognize sulfamethazine (SM₂), forms the shell. The pivotal advancement in this sensor design is the integration of highly fluorescent CdTe quantum dots within the MIPs layer, which significantly enhances the signal response, enabling the detection of SM₂ with remarkable precision. The synthesis of this sensor employs a novel strategy, utilizing 3-aminopropyltriethoxysilane as the functional monomer, while tetraethyl orthosilicate and ammonium hydroxide act as catalysts to facilitate the polymerization reaction. This meticulous process yields a stable core-shell structure with active fluorescent properties. Experimental results reveal that under optimal conditions, the sensor exhibits a robust linear response to SM₂ concentrations ranging from 10 to 60 μmol L⁻¹, with a detection limit as low as 0.78 μmol L⁻¹. Furthermore, when applied to real food samples, such as honey, the sensor not only demonstrates high recovery rates of 92.3%–98.1%, but also maintains a low relative standard deviation of less than 2.5%. The implications of this study are far-reaching, offering a promising avenue for the rapid and reliable monitoring of antibiotic residues in the food supply chain, thereby safeguarding consumer health and upholding food safety standards.     

Preparation of strongly fluorescent silica nanoparticles of polyelectrolyte-protected cadmium telluride quantum dots and their application to cell toxicity and imaging

Based on the polyelectrolyte-protected CdTe quantum dots (QDs), which were prepared by self-assembling of QDs and poly-diallyldimethylammonium chloride (PDADMAC) in the help of electrostatic attraction, the strong fluorescence silica nanoparticles (QDs-PDADMAC@SiO₂) have been prepared via a water-in-oil reverse microemulsion method. Transmission electron microscopy and Zeta potential analysis were used to characterize the as-prepared nanoparticles. All of the particles were almost spherical and there is a uniform distribution of the particle size with the average diameter about 25 nm. There is a large Zeta potential of −35.07 mV which is necessary for good monodispersity of nanoparticles solution. As compared with the QDs coated by SiO₂ (QDs@SiO₂), the QDs-PDADMAC@SiO₂ nanoparticles have much stronger fluorescence, and their fluorescence stability could be obviously improved. Moreover, QDs-PDADMAC@SiO₂ exhibits good biological compatibility which promotes their application in cellular imaging.