海带碳点对斑马鱼胚胎发育的影响

以水产养殖常见的藻类海带为原料,通过水热法绿色、便捷、高效地合成了生物质碳点,全程实现了从原料选择到材料合成的绿色环保无污染。选择斑马鱼模式生物作为研究对象,研究不同浓度碳点在斑马鱼胚胎发育过程中的荧光成像以及代谢情况。并通过研究碳点对斑马鱼胚胎发育的影响,包括孵化率、心率和成鱼存活率等指标,评价了制备的海带碳点的生物安全性。     

基于碳量子点的绿色合成及生物成像研究进展EI北大核心CSCD

碳量子点(CQDs)作为碳纳米材料家族成员之一,因其原材料广、成本低廉、较高的光致发光性能和良好的生物相容性,在研究和应用领域都受到了广泛的关注,是应用于生物成像的理想材料。CQDs的绿色合成是指采用环保型或无毒型原料,通过绿色合成方法,如炭化法、微波法、水热法等,合成具有荧光性能的无毒碳量子点,与传统的化学氧化、激光烧蚀、热解处理等方法相比,更加绿色环保、经济,其应用已成为研究热点。本文对碳量子点材料特性、绿色合成过程机理、绿色合成原料来源、合成方法,及其在癌细胞、微生物细胞等细胞成像方面的应用进行了综述,探讨了绿色合成CQDs的利弊问题,并提出了今后该研究领域面临的机遇与挑战。     

生物质基碳量子点的合成及传感成像研究进展

作为一种碳基发光纳米材料,碳量子点因其毒性低、光学性质可调、成本低廉、优异的光稳定性以及良好的生物相容性等优点,被广泛用于生物传感和生物成像等领域。目前,已经开发了众多的合成碳量子点的方法,其中,采用生物质基天然原料的绿色合成方法,可以利用天然原料或者将低价值废弃物转化为高价值生物质基碳量子点,是未来实现能源可持续发展的趋势。本文主要介绍了生物质基碳量子点的合成方法以及在传感成像领域应用的最新进展,并对生物质基碳量子点在传感成像领域的应用前景和发展方向进行了展望。     

碳点的设计合成、结构调控及应用

碳点是一类环境友好且性能独特的纳米粒子, 在光电转换、 生物医学、 催化及储能等领域的研究日益活跃. 碳点主要分为碳量子点(CQDs)、 石墨烯量子点(GQDs)和碳化聚合物点(CPDs), 其中CPDs作为一种新型碳点, 具有合成原料广泛、 碳化程度及共轭结构可调且材料相容性好等优点. 本文综合评述了近年来碳点尤其是CPDs的合成方法; 阐述了通过选择前驱体分子、 控制反应条件及掺杂原子等手段实现对其碳化和共轭程度、 晶格和能级结构的调控, 从而建立碳点及其杂化与复合材料微纳结构与性能之间的关系; 最后, 介绍了碳点在生物标记与成像、 光(电)催化、 光电转换及储能等领域的应用, 并对碳点领域的发展前景进行了展望.     

基于Cite Space的碳量子点研究热点及趋势可视化分析

利用Cite Space软件梳理了碳量子点领域1998～2021年期间3465篇文献的主要研究信息（国家、机构、作者）,归纳了该领域的研究主题及热点。碳量子点作为一种具有良好荧光性能的碳纳米材料,在荧光检测、传感器、光催化降解等方面得到广泛应用。2011～2021年,碳量子点领域研究呈现高速发展态势。中国科学院、苏州大学及江苏大学等机构的学者在该领域的学术研究十分活跃。该领域的研究主题及热点呈现阶段性特点,2003～2007年,研究主题是碳量子点合成,研究热点是碳量子点的反应活性和转化率;2008～2012年,研究主题是碳量子点合成及发光机理,研究热点是碳量子点的光致发光机理和光催化降解;2013～2017年,研究主题是碳量子点绿色合成和传感器应用,研究热点是碳量子点传感器和检测应用;2018年至今,研究主题是碳量子点传感器以及复合碳量子点材料对有机污染物的光催化降解性能,研究热点是碳量子点在生物传感器,生物检测等领域的应用开发。     

荧光碳点的合成、性质和应用

与传统半导体发光材料相比,荧光碳点作为一种新型的碳纳米发光材料,因其优异的生物相容性、良好的发光性能、简单的合成工艺、低廉的成本等优点而备受关注。荧光碳点在生物荧光标定、医学传感器、光诊疗剂以及发光器件等方面具有广阔的应用潜力。本文重点阐述了荧光碳点的合成方法、显微结构分析、荧光机理及应用的最新成果,希望为荧光碳点合成与应用研究的发展提供参考。     

煤基碳量子点合成研究进展

随着纳米科学技术的出现与发展,各种纳米材料层出不穷,碳量子点以其独特且优异的性质吸引了众多研究者的关注。碳源材料对碳量子点的合成及性质有着重要影响,我国煤炭储量相对丰富,焦炭、煤焦油和煤沥青等煤基衍生物的产量也居于世界前列,煤及煤衍生物富含芳环结构,在微观结构上适宜制备碳量子点。本文主要综述了近年来以煤及煤衍生物为碳源,通过化学试剂氧化、超声和电化学氧化等方法合成碳量子点(统称为煤基碳量子点)的研究进展,阐述了煤及其衍生物作为原料的优势所在,对比分析了不同制备方法的特点,并简要介绍了煤基碳量子点的性质以及其在生物成像、金属离子检测和光催化等领域的应用,最后对煤基碳量子点的可控制备等前景进行了展望。     

碳量子点荧光成像法应用于聚丙烯酰胺凝胶电泳检测人血清蛋白质的研究

建立了碳量子点荧光成像法检测聚丙烯酰胺凝胶电泳分离蛋白质如人血清蛋白质的新方法. 通过一步绿色微波法合成的碳量子点并将其应用在聚丙烯酰胺凝胶电泳分离蛋白质的检测中, 通过醋酸-醋酸钠调节孵育溶液, 优化pH值、碳量子点的用量及孵育溶液的浓度等条件, 使碳量子点和蛋白质相结合并在365 nm的紫外灯照射下得到了清晰的人血清蛋白电泳图, 该新方法具有原料便宜易得、无污染、简单、快速、高灵敏度、低背景及高分辨率的优点, 在生物技术方面和纳米技术方面具有巨大的应用前景.     

酪氨酸微波水热法制备碳点及其在Fe3+检测和荧光标记方面的应用

以酪氨酸为原料,乙二胺为钝化剂,采用绿色、简便的微波辅助水热法制备了尺寸均一、分散性好的碳点.通过调节乙二胺的加入量可以在一定程度上对碳点尺寸进行调节.所得碳点可以通过改变激发波长实现蓝光到绿光的转变,且荧光强度随激发光波长的红移也保持了一定的强度.所得碳点对Fe³⁺具有很好的选择性猝灭,被用于检测Fe³⁺时检测限为0.82 nmol/L,检出限为2.98 nmol/L.所制备碳点具有良好的生物相容性和低细胞毒性,被用于标记AD293细胞时标记位置为细胞质.     

绿色荧光碳点的制备及其在铜检测中的应用

以D-葡萄糖和L-天冬酰胺为原料,通过热解法制备得到绿色荧光碳点。该碳点在Cu2+存在下,碳点荧光发生显著猝灭。基于此,建立了一种可选择性检测Cu2+的方法,在1.0~20.0μmol/L线性范围内对Cu2+呈现良好的响应,检出限为6.3 nmol/L。通过标准加入法将其用于实际水样中Cu2+的检测,回收率为95.2%~105.0%,该碳点可以应用在环境水样中Cu2+的检测。此外,为充分利用该碳点较低的细胞毒性和良好的生物相容性等优点,通过荧光共聚焦成像技术将其成功用于细胞中Cu2+的可视化检测,进一步拓宽了碳点的应用领域。     

氮掺杂碳点的制备及其对阿莫西林高灵敏检测

以天然物质石斛为原料,一步水热法合成高荧光量子产率的氮掺杂碳点(NCDs),通过透射电子显微镜(TEM)、X射线光电子能谱(XPS)、傅里叶变换红外光谱(FT-IR)、紫外-可见光吸收图谱(UV-Vis)及荧光光谱(PL)对合成的NCDs进行表征。 实验结果显示合成的NCDs发强烈的蓝色荧光,呈现为球形或准球形,均匀分散,尺寸范围在1~5 nm;其表面含有丰富的COOH、OH和NH₂等水溶性基团,最佳激发和发射波长分别为350和435 nm,且具有良好的发光稳定性。 通过测定,合成的NCDs的荧光量子产率高达29.19%。在pH=7.4的缓冲溶液中测定不同物质对NCDs的荧光影响,相同条件下发现只有阿莫西林能够对NCDs荧光进行明显猝灭,表明合成的NCDs可选择性的识别阿莫西林,通过NCDs的荧光强度变化构建一种可灵敏检测阿莫西林的传感器,检测线性范围为2.6~30 μmol/L,检出限为0.15 μmol/L。     

Mass production of highly fluorescent full color carbon dots from the petroleum coke

Heavy oil is treated as an undesirable raw material in traditional refining markets because of its low yield. However, its rich natural aromatic structure and heteroatomic compounds make it possible to be a precursor to large-scale production of carbon materials. Using heavy oil and three SDA products as precursors, we synthesized highly fluorescent multi-color carbon dots (CDs) by hydrothermal method, which can precisely control the photoluminescence wavelength in the range of 350?650 nm. The synthesized carbon dots have the advantages of good long-term stability and stability under extreme pH conditions and low price. Importantly, the carbon dots synthesized with asphalt as the precursor have the highest fluorescence quantum yield. X-ray photoelectron spectroscopy (XPS) is used to elucidate the effects of different precursor on emission color change and photoluminescence quantum yield (PLQY), thus providing a controlled tuning of the system for the functionalization of CDs. And we further used the CDs in macrophage labeling. This pathway gives a reliable and repeatable industry possibility and may boost the applications of CDs into reality.     

碳点的合成及对锰离子的比色检测——推荐一个大学化学综合实验

In this experiment, carbon dots were prepared by hydrothermal method with citric acid as raw material. The colorimetric detection of Mn²⁺ was realized via the catalytic oxidation discoloration of Mn²⁺ to 3, 3', 5, 5'-tetramethylbenzidine (TMB) in the mixed system of carbon dots and TMB. Selectivity and sensitivity of the detection were studied by UV-Vis absorption spectrum. This comprehensive experiment covers the preparation and characterization of nanomaterials and the analysis and detection to important substances. It not only exercises students' comprehensive ability to use knowledge and experimental skills, but also helps to broaden students' academic vision.     

Synthesis and bioimaging application of red-emissive carbon dots

Fluorescent red-emissive carbon dots (RCDs) were synthesized using the solvothermal method with citric acid as a carbon source, N,N-dimethylformamide as a nitrogen source, and formamide as a solvent. The as-synthesized RCDs show red fluorescence in an aqueous solution and have an excellent stability towards photobleaching as well as extremely low cytotoxicity and are successfully used for cell and zebrafish imaging. The results indicate that RCDs have potential applications in both in vitro and in vivo bioimaging.     

Environmentally friendly cleaner water-soluble fluorescent carbon dots coated with chitosan: synthesis and its application for sensitivity determination of Cr(VI) ions

In the current work, novel environmentally friendly water-soluble fluorescent carbon dots coated with chitosan (CDs/CTS) were successively synthesized via a facile and green preparation procedure. The fluorescent carbon dots were prepared through a simple, convenient and one-step hydrothermal method in the presence of cellulose as a raw material. The CDs/CTS were connected together via intermolecular hydrogen bonds interaction and chemical bonds between hydroxyl and amino groups in the chitosan polymeric chains and hydroxyl groups of fluorescent carbon dots. This approach can be applied for milligram-scale preparation of these water-soluble particles. The CDs/CTS material showed blue fluorescence under UV exposure. The structure and morphology of as-prepared CDs/CTS were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy. The as-prepared CDs/CTS exhibited excellent fluorescent property and good stability. The fluorescence of as-prepared CDs/CTS could be quenched by the Cr(VI) ions. The effects of environmental factors on the fluorescence intensity were investigated in detail, and the obtained results showed that the optimum conditions for the Cr(VI) ions determination were as follows: 1:3 of mass ratio of CDs/CTS, 9.5 of pH and 20 min of reaction time. Under optimized experimental conditions, a novel fluorescent probe was developed for the detection of Cr(VI) ions, which exhibited wide linear ranges (0–600 μmol/L) and excellent selectivity. The proposed method was directly applied for the determination of Cr(VI) ions in water and soil samples with satisfactory results.     

Chemically and thermally stable,emissive carbon dots as viable alternatives to semiconductor quantum dots for emissive nematic liquid crystal–nanoparticle mixtures with lower threshold voltage

Dispersions of chemically and thermally robust carbon dots (2.5 ± 0.5 nm in core diameter) were prepared and investigated by polarised optical microscopy, electro-optic measurements including dynamic tests and numerical simulations as well as fluorescence confocal microscopy. The carbon dots were prepared by a straightforward thermal decomposition method from citric acid and hexadecylamine, and they show typical excitation wavelength-dependent photoluminescence behaviour. All dispersions, ranging from 0.5 to 5.0 wt.%, showed lower values for isotropic–nematic phase transition temperature and broader isotropic–nematic biphasic temperature intervals with increasing carbon dot content in comparison to the neat material. Doping of the nematic host with the carbon dots resulted in lower values for the apparent threshold voltage and the elastic constants, but higher values for the rotational viscosity. At 2.5 wt.% and higher, carbon dots residing at the confining interfaces in planar cells induce an increasing initial pre-tilt of up to 8° at lower temperatures. Fluorescence confocal microscopy confirmed this, where the luminescence of the carbon dots permitted visualisation of the distribution of the carbon dots in the bulk with a noticeable, in some cases even pattern-like, segregation to the confining interfaces.     

一步水热法制备铜掺杂纳米碳点及其在白光器件中的应用

以一水合乙酸铜和苯胺为原料, 合成了铜掺杂纳米碳点(Cu-CDs). 通过优化实验参数, 确定了合成Cu-CDs的最佳反应时间、 反应温度和原料摩尔比分别为5 h, 210 ℃和1∶1. 与相同条件下的对照实验相比, Cu的掺杂使碳点(CDs)的荧光强度明显提高, 并实现了良好的多色发光性能. 在365 nm紫外光激发下, Cu-CDs可直接发射强烈的白光. 进一步与紫外发光二极管(LED)芯片结合, 得到白色发光器件, 色坐标为(0.337, 0.337), 非常接近纯白光的色坐标(0.33, 0.33). 这种制备Cu-CDs材料的方法及突出的白光发射性能, 拓宽了碳点在发光器件中的应用.     

碳点的制备及荧光量子产率的测定 ——一个仪器分析综合实验

As a new type of nano-materials, carbon dots have unique optical properties and excellent chemical properties, such as easy preparation, low cost, high chemical stability and good biocompatibility. Three kinds of carbon dots were prepared by microwave, hydrothermal and pyrolysis methods, and characterized by infrared spectroscopy. The ultraviolet-visible absorption spectra and fluorescence spectra of the three carbon dots were measured and compared with those of small organic fluorescent molecules. The fluorescence quantum yield of three carbon dots was measured using quinine sulfate as standards. This experiment not only enables students to learn the preparation methods and the unique luminescent properties of carbon nanomaterials, but also enables students to have a deeper understanding of the structures, principles and applications of three kinds of molecular spectroscopy instruments based on the measurement of quantum yield. This experiment can be used as a comprehensive 10-hour instrumental analysis experiment for junior students majoring in chemistry, applied chemistry and material chemistry.     

连翘苷荧光传感器的构建和应用

以柠檬酸为碳源,三聚氰胺和甲醛为双掺杂剂合成碳量子点,并对合成的量子点进行透射电镜(TEM)、傅里叶变换红外光谱(FTIR)、X射线粉末衍射(XRD)、紫外吸收光谱(UV)和荧光光谱(RF)表征,结果表明该量子点粒径均一,发光稳定,适合用作荧光探针。优化了碳量子点含量、pH、反应时间以及温度等影响因素,结果显示检测波长λmax=425 nm时,连翘苷在0.008~0.030 mg/mL范围内有良好的线性关系,1/△f=0.00005(1/c)+0.0003(R2=0.9948),加标回收率在92.5%~106.3%之间,RSD<5%,且干扰物质、反应时间、温度等因素在一定范围内对实验结果的测定无影响。该方法可用于药剂中连翘苷含量的测定。