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量子点的制备及其在生物医学中的应用进展 总被引:1,自引:1,他引:0
量子点作为一种优良的荧光半导体纳米粒子,已成为纳米技术领域最受关注的研究对象之一,并成功应用于生命科学等领域。随着小粒径的低毒无镉量子点的制备和量子点荧光共振能量转移等新技术的发展,量子点在生命科学领域将展示出更大的应用空间。本文介绍了量子点的基本概念和性质,探讨了近年来在有机溶剂和水溶液两种不同介质中制备量子点的方法,并分析比较了其优缺点;对量子点在生物医学领域(包括蛋白质和核酸研究、组分检测、荧光编码及细胞标记等)的应用进行了综述和展望,指出了目前存在的问题和今后的发展方向。 相似文献
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李雪 《合成材料老化与应用》2019,48(6)
将量子点分散在透明硅树脂中并添加固化剂,加热交联固化,获得封装有量子点的硅树脂光学薄膜。采用紫外可见光吸收光谱(UV-Vis)、荧光发射光谱(PL)等方法对光学薄膜的性能进行表征。PL结果表明,量子点薄膜的荧光发射光谱较量子点溶液发生少量红移,而半峰宽则保持一致,量子点光学膜总体上保留了量子点在溶液中93%的荧光量子效率值。制备的量子点膜经高温加速老化后仍然保持约50%的荧光量子效率。 相似文献
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《粘接》2021,48(10)
针对现有量子点影像探针存在荧光性质不可控、生物毒性强的问题,本研究结合现有的CuInS量子点探针,研究制备出一种掺杂Zn离子可简易合成的ZCIS/ZnS量子点纳米探针,并通过改进其水溶性,得到一种可直接应用于医学肿瘤影像的改进ZCIS/ZnS量子点纳米探针。为提高该量子点纳米探针的靶向性,研究根据EDC偶联的原理,通过将改进ZCIS/ZnS量子点纳米探针与cRGD多肽进行偶联,得到ZCIS/ZnS-cRGD量子点纳米探针,并从结构形态、细胞毒性和离体荧光3个方面重点评估了该量子点纳米探针,并通过实验论证了其有效性和实用性。实验结果证明,本研究制备的ZCIS/ZnS-cRGD量子点纳米探针是一种有效的肿瘤靶向探针,可用于实际肿瘤靶向检测。 相似文献
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近年来,半导体纳米晶CdTe引起人们越来越多的关注。它具有吸收光谱宽,发射光谱窄而对称,发光颜色可调,荧光强度和光稳定性高等特点,已经广泛用于生物标记,生物传感及生物检测领域。尤其在基于荧光共振能量转移原理的生物传感领域,量子点有望取代有机荧光发色基团作为能量供体。在文章实验中,以巯基丙酸(MPA)作为稳定剂,在水相中合成了CdTe量子点,并考察了回流时间,反应温度,溶液pH对CdTe光学性质的影响。利用透射电子显微镜(TEM),荧光分光光度计(FS)等手段对产物进行分析和表征。结果表明:在pH为9.1,反应温度为30℃,回流5 h,可以实现CdTe的优化合成。在紫外灯(254 nm)照射下,回流时间从1 h到7 h所得到的CdTe量子点,颜色由绿色变到黄色,对应的荧光光谱图的吸收峰位从515 nm(回流1 h)红移到573 nm(回流7 h),证实了CdTe量子点的尺寸随着回流时间的增长而增加。由TEM结果,所合成的CdTe量子点分散性好,且粒径大约在5 nm左右。该本实验制备的CdTe量子点具有较高的荧光强度和量子效率,将在生物标记,生物传感,生物成像等领域有重要作用。 相似文献
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Wen Mi Jintao Tian Weiguo Tian Jinhui Dai Xin Wang Xiaoyun Liu 《Ceramics International》2012,38(7):5575-5583
The CdSe quantum dots (QDs) were synthesized at various temperatures in aqueous solution. The as-synthesized QDs were characterized by X-ray diffraction (XRD) method and transmission electron microscopy (TEM), and their optical properties were assessed via ultraviolet–visible (UV–vis) absorption spectrum and fluorescence spectrum. The results showed that the reaction temperature could significantly influence the band gap, particle size, and spectral behaviors of the QDs. With the increase of the temperature from room temperature to 90 °C, the band gap of the QDs linearly decreased, corresponding to an essential increase of particle size as well as variable spectral behaviors. In particular, the starting temperature had an important effect on the QDs synthesis and their optical properties. From a viewpoint of wide controls of fluorescence color and intensity, a reaction temperature range of 17–90 °C was appropriate for the synthesis of the CdSe QDs. 相似文献
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Yun-Peng Zhang Peng Sun Xu-Rui Zhang Wu-Li Yang Cheng-Shuai Si 《Nanoscale research letters》2013,8(1):294
The purpose of this experiment was to investigate the visible imaging of gastric adenocarcinoma cells in vitro by targeting tumor-associated glycoprotein 72 (TAG-72) with near-infrared quantum dots (QDs). QDs with an emission wavelength of about 550 to 780 nm were conjugated to CC49 monoclonal antibodies against TAG-72, resulting in a probe named as CC49-QDs. A gastric adenocarcinoma cell line (MGC80-3) expressing high levels of TAG-72 was cultured for fluorescence imaging, and a gastric epithelial cell line (GES-1) was used for the negative control group. Transmission electron microscopy indicated that the average diameter of CC49-QDs was 0.2 nm higher compared with that of the primary QDs. Also, fluorescence spectrum analysis indicated that the CC49-QDs did not have different optical properties compared to the primary QDs. Immunohistochemical examination and in vitro fluorescence imaging of the tumors showed that the CC49-QDs probe could bind TAG-72 expressed on MGC80-3 cells. 相似文献
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Peng Liu Yisi Liu Qisui Wang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(12):1670-1675
BACKGROUND: Quantum dots (QDs) have attracted much attention in biological and medical applications. In particular, the interaction of QDs with bovine serum albumin (BSA) is crucial, and has been systematically investigated by various spectroscopic techniques under the physiological conditions. RESULTS: The effects of ionic strength and pH on the interaction of CdTe QDs with BSA were studied by changing NaCl concentration and pH in mixed solution and making fluorescence spectroscopic measurements. The Stern‐Volmer quenching constant (Ka) of different ionic strength and pH were calculated, and information on the structural features of BSA were discussed by means of circular dichroism (CD) spectrum. CONCLUSION: Both fluorescence (FL) and circular dichroism (CD) results indicated that hydrophobic and electrostatic interactions play a major role in the binding reaction, and the nature of quenching is static, resulting in forming QDs‐BSA complexes. Copyright © 2012 Society of Chemical Industry 相似文献
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以巯基乙酸为稳定剂在水相中合成了CdTe量子点,并将合成的CdTe量子点进行表征、纯化。通过用0.05 mol.L-1PBS缓冲溶液调节不同的pH来考察量子点的荧光强度和pH的关系。研究发现,水溶性的CdTe量子点是pH敏感的,随着pH值的降低,量子点荧光强度的下降规律与溶液pH值呈现良好的线性关系。结果表明,CdTe量子点是一个令人满意的pH敏感的探针,有潜在的化学和生物传感能力。 相似文献
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在水相中合成高发光性能的CdTe量子点,研究以巯基乙酸(TGA)为稳定剂对CdTe表面进行修饰,制备在水中分散性良好的纳米晶,通过对CdTe量子点合成反应条件的摸索,掌握了其合成的反应规律.同时用紫外分光光度计、荧光分光光度计和透射电子显微镜对其进行了表征.结果表明,回流时间、n(Cd2+):n(HTe-)、反应物浓度、TGA用量、反应体系pH值,对纳米晶的光学性质具有显著影响.回流2 h制得的CdTe纳米粒子直径约为5 nm,其发射峰窄且对称,表现出良好稳定的光学性质. 相似文献
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The design of fluorescent probes for turn-on sensing of anions has been especially significant because it can effectively enhance sensing sensitivity by decreasing the background interference. In the present work, we have systematically studied the potential applications of fluorescent quantum dots (QDs) in turn-on anion sensing. The fluorescence of QDs are firstly quenched by three different mechanisms, i.e. fluorescence resonance energy transfer, electron transfer and surface states modulated fluorescence. The fluorescence of the pre-quenched QDs can then be recovered by various anions due to the modulating effects of added anions on the interaction between QDs and QDs, the interaction between QDs and quenchers, and the surface chemistry of the quenched QDs, respectively. The results described here indicate that turn-on sensing of various anions by QDs-based systems can be achieved by rationally choosing fluorescence modulating strategies, demonstrating the versatility of QDs in the corresponding applications. 相似文献
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Transparent poly(styrene‐butadiene‐styrene) (SBS)‐quantum dots (QDs) composites (SBS/CdTe QDs) that simultaneously possess strong photoluminescence (PL) and enhanced mechanical properties are presented for the first time based on the facile blending of SiO2‐hybridized CdTe QDs with SBS. UV–vis spectrum and fluorescence measurement show that SBS/CdTe QDs composites exhibit good optical properties. The results of transmission electron microscopy show good dispersion of CdTe QDs in the SBS matrix. The results of dynamic mechanical thermal analysis indicate that the micro‐phase separated structure of the SBS is exist in the composites, and the presence of CdTe QDs can lead to an decrease of glass transition temperatures of polybutadiene (PB) and polystyrene(PS) domains. In addition, mechanical tests reveal that the addition of CdTe QDs is a useful approach to improve the mechanical properties of SBS. Meanwhile, the fluorescent photographs taken under ultraviolet light prove that SBS/CdTe QDs composites possess strong PL. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. 相似文献