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以草酸和尿素为碳源,超纯水为溶剂,采用微波方法快速合成了具有热敏性的氮掺杂碳量子点,对其形貌、结构、荧光性质和荧光强度的影响因素,以及细胞毒性进行了测试和讨论,并用于小鼠结肠癌细胞(CT26.WT)成像。结果表明,制备的碳量子点近似球形,粒径约3.8 nm。碳量子点具有良好的温度响应的荧光性质。在10~80℃温度范围内,相对荧光强度与温度之间存在良好的线性关系。随着温度的增加,碳量子点的荧光强度减小,温度从10℃升至80℃,相对荧光强度减少了25%,当温度反向降低时,其荧光强度恢复到原始值。碳量子点温度与荧光强度之间的线性关系,使之在温度响应的荧光传感领域具有潜在的应用价值。对碳量子点进行氮掺杂能有效提高其荧光量子产率,当草酸和尿素质量比为3∶1时,荧光量子产率最高,为9.5%。另外,合成的碳量子点还具有优异的抗盐性能、强稳定性等特点,不仅能有效被CT26.WT细胞吞噬,还显示出低毒性和生物相容性,MTT分析结果表明,在1 000μg·mL~(-1)的碳量子点存在下,CT26.WT细胞存活率达85%,荧光碳量子点有望作为温敏性的荧光纳米探针在细胞研究领域得到应用。 相似文献
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以银杏叶为原料,采用水热法制备得到新型荧光碳量子点(CQDs)。该碳量子点的平均粒径为5.5 nm,最大激发波长为335 nm,最大发射波长为418 nm。基于碳量子点荧光光谱与苦味酸(PA)吸收光谱存在部分重叠而发生荧光共振能量转移(FRET),建立了以碳量子点作为荧光探针用于苦味酸检测的新方法。在最佳实验条件下,加入苦味酸前、后的荧光强度比值(I0/I)与苦味酸浓度(c)在0.2~800μmol/L范围内呈良好的线性关系,相关系数(r)为0.999 5,检出限(LOD)为32 nmol/L。在5、40、80μmol/L加标水平下,实际水样中苦味酸的回收率为98.0%~104%,相对标准偏差(RSD)为1.0%~3.2%。该方法可用于实际样品中苦味酸的灵敏、快速和高效检测。 相似文献
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以木炭为碳源,采用回流的方法制备了碳量子点。用荧光光谱、紫外光谱法研究了该碳量子点与法莫替丁的相互作用。实验发现,在pH为7.1的Tris-HCl缓冲溶液中,法莫替丁的加入可使碳量子点荧光信号显著增强,其浓度在8.0×10~(-9)~1.0×10~(-7) mol/L范围内与碳量子点荧光信号强度的增加值△F呈良好的线性关系,相关系数r为0.9993。据此,提出了以碳量子点为荧光探针测定法莫替丁的新方法,方法检出限(3s/k)为2.0×10~(-9) mol/L。该方法简便、快捷、灵敏,应用于样品中法莫替丁含量的测定,回收率范围为98.50%~103.2%。 相似文献
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以3-氨基苯硼酸为功能单体,葡萄糖为模板分子,在碳量子点和壳聚糖修饰的玻碳电极表面电聚合生成分子印迹聚合物膜,构建了无酶分子印迹电化学传感器,用于葡萄糖的高灵敏测定。采用循环伏安法(CV)、交流阻抗法(EIS)和差分脉冲伏安法(DPV)研究传感器的电化学特性及分析特性。在最优条件下,DPV电流响应的变化值与葡萄糖浓度在0.1~1.0μmol/L和1.0~300μmol/L范围内分别呈现良好的线性关系,线性方程分别为ΔIp(μA)=3.792+23.41C (R2=0.9968)和ΔIp(μA)=28.18+0.1316C (R2=0.9914),检出限为0.034μmol/L (3σ/k)。将此传感器应用于体液中葡萄糖的测定,回收率为95.1%~106.8%。 相似文献
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利用电化学方法在碱性条件下电解石墨棒, 通过常温下水合肼还原, 得到5~10 nm的荧光石墨烯量子点(Graphene Quantum Dots, GQDs). 通过透射电子显微镜(TEM)、原子力显微镜(AFM)对所制备的GQDs进行形貌表征, GQDs的粒子大小均一, 为单层石墨烯. 通过傅里叶变换红外光谱(FTIR)、荧光光谱(PL)、紫外可见吸收光谱(UV-vis)、X 射线衍射光谱(XRD)对所制备的GQDs进行性质测定, 发现GQDs可以发出黄色荧光, 量子产率为14%, 毒性低、具有良好的水溶性、荧光稳定性和生物兼容性, 可顺利进入细胞, 在肿瘤细胞的成像研究方面具有广泛的应用前景. 相似文献
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Jie Guo Mengyu Guo Fuhui Wang Weiyue Jin Chunying Chen Huibiao Liu Yuliang Li 《Angewandte Chemie (International ed. in English)》2020,59(38):16712-16716
Graphdiyne (GDY) as an emerging two‐dimensional carbon allotrope exhibits excellent performance in energy chemistry, catalytic chemistry, optoelectronics, electronics, etc. because of the unique structure combining an sp‐ and sp2‐hybrid carbon network. However, the poor solubility of pristine GDY is a major obstacle to its applications in many fields. Proposed here is a facile strategy to control the preparation of GDY quantum dots (GDY‐Py QDs), in which pyrene groups are covalently linked to GDY by using a Sonogashira cross‐coupling reaction. The as‐prepared GDY‐Py QDs, with an average diameter of about 3±0.1 nm, show superior dispersibility in many organic solvents and water. The GDY‐Py QDs display not only bright fluorescent with a high relative quantum yield (QY) of 42.82 %, but they are also well‐behaved as contrast agents in cell imaging. The GDY‐Py QDs are bestowed with high stability and non‐cytotoxicity, and exhibit long fluorescent times, and have potential for optical imaging and biomedical applications. 相似文献
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Here, based on self-assembly of carbon quantum dots (CDs), an innovative method to prepare nanomaterials under the action of a metal catalyst was presented. CDs were synthesized by a one-step hydrothermal method with citric acid (CA) as the carbon source, ethylenediamine (EDA) as the passivator and FeSO4•7H2O as the pre-catalyst. In the experiment, it was found that the nano-carbon films with a graphene-like structure were formed on the surface of the solution. The structure of the films was studied by high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared (FT-IR), etc. The results demonstrated that the films were formed by the self-assembly of CDs under the action of the gas–liquid interface template and the metal catalyst. Meanwhile, the electrochemical performance of the films was evaluated by linear cyclic voltammetry (CV) and galvanostatic charge discharge (GOD) tests. In addition, the bulk solution could be further reacted and self-assembled by reflux to form a bifunctional magnetic–fluorescent composite material. Characterizations such as X-ray diffractometer (XRD), fluorescence spectra (FL), vibrating sample magnetometer (VSM), etc. revealed that it was a composite of superparamagnetic γ-Fe2O3 and CDs. The results showed that self-assembly of CDs is a novel and effective method for preparing new carbon nanomaterials. 相似文献
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荧光碳点探针是近几年来发展起来的一种新型荧光探针,具有传统有机染料、荧光染色蛋白及一般荧光纳米材料无法比拟的独特优势,如具有良好的水溶性、化学惰性、低毒性、易于功能化、抗光漂白性、可调谐和生物相容性等优异性能,因而引起研究者的广泛关注。目前已发展水热法等近十种较为经济便捷的方法,可进行大规模的荧光碳点制备,在细胞功能研究及细胞表面和内部功能分子的探测、组织的成像、病菌的定位等方面得到了较为广泛的应用。笔者对近年来荧光碳点的合成方法、依赖于碳点尺寸和波长等性质的发光性能,以及荧光碳点在生物成像等方面的应用作一简要综述,并对其在药用植物病理方面的应用提出展望,期望为丰富荧光碳点在生物成像领域的应用提供一定的借鉴和参考。 相似文献
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The aim of this study was to establish a rapid detection method of rutin in food based on nitrogen-doped carbon quantum dots (N-CDs) as the fluorescent probe. N-CDs were prepared via a single-step hydrothermal process using citric acid as the carbon source and thiourea as the nitrogen source. The optical properties of N-CDs were characterized using an electron transmission microscope, X-ray diffractometer, Fourier-transform infrared spectrometer, and nanoparticle size potential analyzer. The UV/Vis absorption property and fluorescence intensity of N-CDs were also characterized using the respective spectroscopy techniques. On this basis, the optimal conditions for the detection of rutin by N-CDs fluorescent probes were also explored. The synthesized N-CDs were amorphous carbon structures with good water solubility and optical properties, and the quantum yield was 24.1%. In phosphate-buffered solution at pH = 7.0, Rutin had a strong fluorescence-quenching effect on N-CDs, and the method showed good linearity (R2 = 0.9996) when the concentration of Rutin was in the range of 0.1–400 μg/mL, with a detection limit of 0.033 μg/mL. The spiked recoveries in black buckwheat tea and wolfberry were in the range of 93.98–104.92%, the relative standard deviations (RSD) were in the range of 0.35–4.11%. The proposed method is simple, rapid, and sensitive, and it can be used for the rapid determination of rutin in food. 相似文献
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石墨相氮化碳量子点的制备及应用的研究进展 总被引:1,自引:0,他引:1
近年来,石墨相氮化碳(g-C3N4)因其稳定的物理化学性能和良好的生物相容性而受到研究者关注。与块体g-C3N4相比,石墨相氮化碳量子点(g-CNQDs)尺寸更小、荧光效率更高,且具有量子限域效应,因此拥有特殊的理化性质与更好的光催化性能。本文主要从g-CNQDs的制备策略和应用展开讨论,着重综述了微波辅助法、低温固相法、热化学腐蚀法和电化学刻蚀法制备g-CNQDs,以及g-CNQDs在催化剂、离子检测、生物传感与诊疗等领域的最新应用研究进展;指出了目前g-CNQDs在性质、制备和应用等研究方面的重点和难点;最后对g-CNQDs存在的问题和未来的发展方向作出了展望。 相似文献
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荧光碳点由于其具有无毒、制备成本低以及独特的光致发光性能而引起人们极大的研究兴趣,但是通常碳点的制备和使用均是在溶液中,而且随着碳点浓度的增加其荧光强度可能会降低甚至猝灭,通过简单干燥后得到的固态粉末则常常缺少荧光性质。因此,固态荧光碳点制备及其相关应用的研究相对较少。本文综述了固态荧光碳点的制备方法,包括后处理法(基质分散法、表面工程法)和前驱体直接合成法;对比了各种调控手段处理前后碳点荧光性能的变化情况,总结了各种固态碳点在制备过程中和使用过程中存在的主要问题。最后,针对固态发光碳点的制备方法、性能调控及发展方向进行了展望。开发具有聚集诱导发射增强的碳点是至关重要的,也为固态碳点的发展提供了新思路。 相似文献
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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。 相似文献
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Raphaël de Boëver Jason R. Town Xu Li Prof. Jerome P. Claverie 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(47):e202200748
Carbon Dots (CDs) are carbon nanoparticles which were discovered in 2004. Despite two decades of intensive work from the scientific community and a colossal amount of gathered experimental data, no definitive consensus exists to date on several key aspects such as the actual definition of CDs and the origin of their emissive properties. This review proposes a critical evaluation of these fundamental questions. Lay persons will also find here an alternative introduction to the CDs domain, including synthetic strategies, photophysical properties, as well as challenges and outlook of this exciting new area. 相似文献