共查询到17条相似文献,搜索用时 93 毫秒
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光漂白是光动力疗法(Photodynamic therapy,PDT)中的一个伴随过程,其存在会影响光敏剂的光敏性能并消耗光敏剂.初步探讨了基于量子点CdSe的光动力疗法中两次给药的问题、给药最佳时间间隔、二次给药的最佳作用参数及正常的与药物处理过的白血病HL60细胞表面的超微结构变化.实验表明,一次给药在量子点浓度为1.0 μmol/L且18 J/cm2的光剂量作用下,PDT效率达到61.0%;经过48 h后,进行二次给药,在量子点浓度为0.75 μmol/L,18 J/cm2光剂量作用下,PDT效率达到了72.1%,较一次给药有了较大幅度提升;扫描电子显微镜(SEM)观察药物作用前后的白血病HL60细胞表面超微结构,结果显示,细胞表面发生了一些显著的变化,由此推测细胞膜可能是量子点CdSe介导的光动力疗法(CdSe-PDT)灭活白血病HL60细胞的一个重要突破口;最后对量子点CdSe光致毒性的机制进行了初步探讨. 相似文献
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半导体量子点具有长时间、多目标和灵敏度高等独特的光化学性质,这些特性使量子点成为细胞标记和生物应用中得到了广泛的应用。利用量子点目标定位癌细胞,对于寻找癌变部位具有指导的作用。近年来,利用量子点作为光动力学治疗癌症的能量供体也得到了一定的研究。简单地介绍了量子点独特的光学性质,并从量子点标记癌细胞、可视化癌细胞表面功能和在光动力学治疗癌症等方面综述了量子点在癌症诊断和治疗中的应用。 相似文献
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上转换纳米颗粒具备光学/化学稳定性高、生物毒性低、荧光寿命长及激发光生物组织穿透深度较大等显著优点,近年来在生物传感、生物成像和疾病治疗等生物医学领域的研究和应用获得了广泛的关注。本文中,笔者就稀土元素掺杂的上转换纳米颗粒在肿瘤的诊断与治疗方面的研究现状及进展进行综合概述,主要对其在光动力疗法(PDT)、光热疗法(PPT)、化学联合疗法及多模态诊疗一体化等方面的研究展开分析和讨论,为上转换纳米颗粒的进一步研究开发及临床应用提供新的参考方向及思路。 相似文献
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《激光生物学报》2021,(1)
光动力疗法是目前临床上出现的一种新型治疗肿瘤的方法,利用光敏剂吸收可见-近红外光并在组织氧的参与下发生光化学反应,产生活性氧物质进而诱导肿瘤细胞凋亡或坏死。光动力疗法对肿瘤侵袭性低,具有较高的选择性和良好的患者依从性,因此被广泛用于各种消化道恶性肿瘤的姑息性治疗和挽救性治疗。本文对近年来国内外应用光动力疗法治疗消化道肿瘤的文献进行综述,对所报道的疾病类型、治疗病例数、光敏剂和光源、疗效和安全性等信息进行分类整理,并对所面临的挑战和近期的研究进展进行了汇总,以期全面和客观地了解光动力疗法在治疗消化道肿瘤中的应用和研究进展,探讨目前的新应用及存在的问题和可能的发展方向。 相似文献
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组织氧合作用和光敏剂应用在疾病诊治中都有着重要的作用,因此其实时在体无损检测很有意义。光动力疗法涉及光敏剂、光和氧分子三大要素,其疗效受组织氧合作用影响。本文对光声成像(PAI)、光声寿命成像(PALI)和多光谱光声层析成像(MSOT)等光声成像技术在光动力疗法的研究和应用中的使用现状进行了综述。对相关设备系统在检测光敏剂、组织氧分压和微血管损伤等方面的应用原理和技术分别进行了介绍,并总结了这些技术的应用前景。 相似文献
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Vasudevanpillai Biju Sathish Mundayoor Ramakrishnapillai V. Omkumar Abdulaziz Anas Mitsuru Ishikawa 《Biotechnology advances》2010
Semiconductor quantum dots (QDs) are nanoparticles in which charge carriers are three dimensionally confined or quantum confined. The quantum confinement provides size-tunable absorption bands and emission color to QDs. Also, the photoluminescence (PL) of QDs is exceptionally bright and stable, making them potential candidates for biomedical imaging and therapeutic interventions. Although fluorescence imaging and photodynamic therapy (PDT) of cancer have many advantages over imaging using ionizing radiations and chemo and radiation therapies, advancement of PDT is limited due to the poor availability of photostable and NIR fluorophores and photosensitizing (PS) drugs. With the introduction of biocompatible and NIR QDs, fluorescence imaging and PDT of cancer have received new dimensions and drive. In this review, we summarize the prospects of QDs for imaging and PDT of cancer. Specifically, synthesis of visible and NIR QDs, targeting cancer cells with QDs, in vitro and in vivo cancer imaging, multimodality, preparation of QD-PS conjugates and their energy transfer, photosensitized production of reactive oxygen intermediates (ROI), and the prospects and remaining issues in the advancement of QD probes for imaging and PDT of cancer are summarized. 相似文献
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Construction of photodynamic‐effect immunofluorescence probes by a complex of quantum dots,immunoglobulin G and chlorin e6 and their application in HepG2 cell killing 下载免费PDF全文
Zheng‐Yu Yan Li‐Li Wang Meng‐Ying Fei Xin‐Ying Liu Yi‐Long Su Qing‐Qing Du Sheng‐Mei Wu 《Luminescence》2016,31(6):1174-1181
In this study, tri‐functional immunofluorescent probes (Ce6–IgG–QDs) based on covalent combinations of quantum dots (QDs), immunoglobulin G (IgG) and chlorin e6 (Ce6) were developed and their photodynamic ability to induce the death of cancer cells was demonstrated. Strategically, one type of second‐generation photosensitizer, Ce6, was first coupled with anti‐IgG antibody using the EDC/NHS cross‐linking method to construct the photosensitive immunoconjugate Ce6–IgG. Then, a complex of Ce6–IgG–QDs immunofluorescent probes was obtained in succession by covalently coupling Ce6–IgG to water soluble CdTe QDs. The as‐manufactured Ce6–IgG–QDs maintained the bio‐activities of both the antigen–antibody‐based tumour targeting effects of IgG and the photodynamic‐related anticancer activities of Ce6. By way of polyclonal antibody interaction with rabbit anti‐human epidermal growth factor receptor (anti‐EGFR antibody, N‐terminus), Ce6–IgG–QDs were labelled indirectly onto the surface of human hepatocarcinoma (HepG2) cells in cell recognition and killing experiments. The results indicated that the Ce6–IgG–QDs probes have excellent tumour cell selectivity and higher photosensitivity in photodynamic therapy (PDT) compared with Ce6 alone, due to their antibody‐based specific recognition and location of HepG2 cells and the photodynamic effects of Ce6 killed cells based on efficient fluorescence resonance energy transfer between QDs and Ce6. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Ebrahim Forati Abas Sabouni Supriyo Ray Brian Head Christian Schoen Dan Sievenpiper 《PloS one》2015,10(12)
Receptor coated resonant nanoparticles and quantum dots are proposed to provide a cellular-level resolution image of neural activities inside the brain. The functionalized nanoparticles and quantum dots in this approach will selectively bind to different neurotransmitters in the extra-synaptic regions of neurons. This allows us to detect neural activities in real time by monitoring the nanoparticles and quantum dots optically. Gold nanoparticles (GNPs) with two different geometries (sphere and rod) and quantum dots (QDs) with different sizes were studied along with three different neurotransmitters: dopamine, gamma-Aminobutyric acid (GABA), and glycine. The absorption/emission spectra of GNPs and QDs before and after binding of neurotransmitters and their corresponding receptors are reported. The results using QDs and nanorods with diameter 25nm and aspect rations larger than three were promising for the development of the proposed functional brain mapping approach. 相似文献
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In this paper, we described the preparation and characterization of different types of modified CdSe/ZnS quantum dots (QDs) and explored the biological effects of QDs with different surface modifications on the whole growth of unicellular protozoan Tetrahymena thermophila BF(5) using a thermal activity monitor air isothermal microcalorimeter. Our results demonstrated that adenosine 5'-monophosphate (AMP) showed stronger interaction with QDs than other types of nucleotide. AMP-QDs could stimulate the growth of T. thermophila while mercaptoacetic acid-capped CdSe/ZnS quantum dots inhibited it. In addition, the population density determination and fluorescence imaging of T. thermophila BF(5) also confirmed the results obtained from microcalorimetry. It is believed that this approach will provide a more convenient methodology for the kinetics and thermodynamics of microorganism when coexisting with QDs in real time, and all of which are very significant to understanding the effect of QDs to organism. 相似文献
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由于具有优异的光学特性,量子点在生物医学领域内的研究和应用取得了一些有意义的进展,同时也引起了新药开发人员的兴趣.本文概述了量子点在新药开发中所具有的优势,分析了量子点在药物传输、药物筛选和药靶确证方面的潜在应用,进一步讨论了当前量子点应用于新药开发存在的问题和不足. 相似文献
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Loginova YF Dezhurov SV Zherdeva VV Kazachkina NI Wakstein MS Savitsky AP 《Biochemical and biophysical research communications》2012,419(1):54-59
CdSe-core, ZnS-capped semiconductor quantum dots (QDs) are of great potential for biomedical applications. However, applications in the gastrointestinal tract for in vivo imaging and therapeutic purposes are hampered by their sensitivity to acidic environments and potential toxicity. Here we report the use of coatings with a combination of polythiol ligands and silica shell (QDs PolyT-APS) to stabilize QDs fluorescence under acidic conditions. We demonstrated the stability of water-soluble QDs PolyT-APS both in vitro, in strong acidic solutions, and in vivo. The biodistribution, stability and photoluminescence properties of QDs in the gastrointestinal tract of mice after per os administration were assessed. We demonstrated that QDs coated with current traditional materials - mercapto compounds (QDs MPA) and pendant thiol group (QDs PolyT) - are not capable of protecting QDs from chemically induced degradation and surface modification. Polythiol ligands and silica shell quantum dots (QDs PolyT-APS) are suitable for biological and biomedical applications in the gastrointestinal tract. 相似文献