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Guang‐Rong Tan Menghan Wang Chin‐Ying Hsu Nanguang Chen Yong Zhang 《Advanced Optical Materials》2016,4(7):984-997
Rapid progress in biological sensing and imaging technologies offers new and exciting opportunities to identify biochemical changes fundamental to preclinical research that may develop into the next generation of point‐of‐care devices. Small upconverting fluorescent nanoparticles (UCNPs) are a special class of lanthanide‐doped, optically active, microscopic particles that fluoresce upon near‐infrared light activation. With the additional advantages of deep penetration, minimal photodamage, and low background fluorescence in biological tissues, biosensors incorporating these lanthanide nanoparticles are rapidly emerging as serious contenders to rival the traditional downconversion‐based fluorescence nanoparticles. Emphasizing on two application areas, namely biosensing and bioimaging, the recent developments in lanthanide‐based UCNP design for optimum upconversion efficiency are reviewed. The article discusses the use of UCNPs in biosensing and bioimaging, highlights the challenges that hamper further applications, and concludes with future directions. 相似文献
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Philipp Reineck Adam Francis Antony Orth Desmond Wai Mo Lau Reece David Valmont Nixon‐Luke Ishan Das Rastogi Wan Aizuddin Wan Razali Nicole Maree Cordina Lindsay Marie Parker Varun Kumaraswamy Annayya Sreenivasan Louise Jennifer Brown Brant Cameron Gibson 《Advanced Optical Materials》2016,4(10):1549-1557
Many novel fluorescent nanomaterials exhibit radically different optical properties compared to organic fluorophores that are still the most extensively used class of fluorophores in biology today. Assessing the practical impact of these optical differences for bioimaging experiments is challenging due to a lack of published quantitative benchmarking data. This study therefore directly and quantitatively compares the brightness and photostability of representatives from seven classes of fluorescent materials in spectroscopy and fluorescence microscopy experiments for the first time. These material classes are: organic dyes, semiconductor quantum dots, fluorescent beads, carbon dots, gold nanoclusters, nanodiamonds, and nanorubies. The relative brightness of each material is determined and the minimum material concentrations required to generate sufficient contrast in a fluorescence microscopy image are assessed. The influence of optical filters used for imaging is also discussed and suitable filter combinations are identified. The photostability of all materials is determined under typical imaging conditions and the number of images that can be acquired is inferred. The results are expected to facilitate the transition of novel fluorescent materials from physics and chemistry into biology laboratories. 相似文献
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Han Jie Wang Rishav Shrestha Yong Zhang 《Particle & Particle Systems Characterization》2014,31(2):228-235
Photodynamic therapy (PDT) is a promising method for cancer therapy. However, it is constrained by limited penetration depth of visible light, hydrophobicity of photosensitizers, and lack of tumor targeting. In this work, the photosensitizer zinc phthalocyanine (ZnPc) and upconversion nanocrystals (UCNs) are encapsulated into OQPGA‐PEG/RGD/TAT lipid micelles. The UCNs acting as a nanotransducer convert deep‐penetrating near‐infrared (NIR) light to visible light for activating the photosensitizer. OQPGA‐PEG/RGD/TAT lipid micelles are used as a carrier for the photosensitizer, with improved biocompatibility and cancer‐targeting ability. The results show that the photosensitizer ZnPc‐ and UCNs‐loaded OQPGA‐PEG/RGD/TAT lipid micelles are nanoparticles with an average size of 25 nm. The lipid micelle nanoparticles are stable in water with low leakage of photosensitizer. The absorption peak of the photosensitizer overlaps with the emission peak of UCNs, so the visible fluorescence emitted from the UCNs upon excitation by the NIR laser at 980 nm can activate the photosensitizer to produce singlet oxygen for PDT. The targeting RGD peptide and cell‐penetrating TAT peptide on the surface help the nanoparticles getting into cancer cells. The OQPGA‐PEG/RGD/TAT lipid micelles encapsulated with both the photosensitizer ZnPc and UCNs could be used for targeted PDT by using deep‐penetrating NIR light as the light source. 相似文献
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Surface capping is an essential component of nanoparticles as it provides access to their outstanding properties in the real world. Upconversion nanoparticles are predominantly interesting for use in biological environments, due to their excellent optical properties such as the conversion of near‐infrared excitation light into emissions in the visible or UV range of the spectrum, high photostability, and the absence of any intermittence. One of the most efficient upconversion nanoparticles, consisting of lanthanide doped NaYF4, suffers from limited stability in aqueous media. This study investigates a set of five types of surface coatings, ranging from small ligands to polymers of different charge and different coordinating groups, on monodisperse 28 ± 0.9 nm sized NaYF4(Yb,Er) nanoparticles modified by a two‐step ligand exchange mediated by NOBF4. Information on the long‐term chemical and colloidal stability for highly diluted aqueous dispersions of these particles is acquired by transmission electron microscopy, dynamic light scattering, and luminescence spectroscopy. The findings are of importance for the development of probes and labels based on upconversion nanoparticles for biological applications. 相似文献
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在反应温度为200℃、反应时间为8h的温和条件下,采用水热法合成了近红外到近红外的Mn2+掺杂NaYF4:Yb3+/Tm3+上转换荧光纳米粒子,再以两亲性聚合物C18PMH-mPEG作为亲水性配体修饰到上转换荧光纳米粒子表面,得到具有水溶性的上转换荧光纳米粒子。然后在980nm近红外光源激发下,测量了上转换荧光纳米粒子的荧光发射光谱,在（800±10）nm附近,观察到了较强的单近红外光发射（3H4→3H6）。对样品进行细胞毒性实验,结果表明制得的水溶性Mn2+掺杂NaYF4:Yb3+/Tm3+纳米粒子具有良好的生物相容性。并进一步在小鼠体内进行了近红外成像,表明其在生物成像领域将会具有一定的应用前景。 相似文献
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利用水热法制备得到NaYbF4:0.01%Tm3+,20%Eu3+上转换材料,利用X射线衍射分析、扫描电子显微镜及光谱测试技术分别对其进行了结构、形貌以及光谱性质的表征。在980 nm近红外激光激发下,得到了Eu3+的可见到紫外范围的上转换荧光发射。分析表明:共掺杂NaYbF4纳米材料中Tm3+到Eu3+离子的能量传递对布居Eu3+离子的激发态能级,获得Eu3+的上转换发光起着至关重要的作用。另外,在实验中首次获得了Eu3+对应于3P0→7Fj (j=0,1,2)能级跃迁的上转换光发射。 相似文献
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《Advanced Optical Materials》2017,5(2)
A great challenge in noninvasive biomedical imaging is the acquisition of images inside a biological system at the cellular level. Common modalities used today such as magnetic resonance or computed tomography imaging have the advantage that any part of a living organism can be imaged at any depth, but are limited to millimeter resolution and can usually not be employed e.g., for surgical guidance. Optical imaging techniques offer resolution on the 100 nanometer scale, but are limited by the strong attenuation of visible light by biological matter and are traditionally used to image on the surface. Near‐infrared light in the “biological windows” can penetrate much deeper into biological samples, rendering fluorescence‐based imaging a viable alternative. In the past two decades, many fluorescent nanomaterials have been developed to operate in the near infrared, yet only few materials emitting above 1000 nm exist and none are approved for clinical use. This review describes recent advances in the development and use of near‐infrared fluorescent nanomaterials for biomedical imaging and sensing applications. The physical and chemical properties as well as the bioconjugation and application of materials such as organic fluorophores, semiconductor quantum dots, carbon‐based materials, rare earth materials, and polymer particles are discussed. 相似文献
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Xiaohui Xu Aveek Dutta Jacob Khurgin Alexander Wei Vladimir M. Shalaev Alexandra Boltasseva 《Laser u0026amp; Photonics Reviews》2020,14(5)
Metal–semiconductor heterostructures have attracted a lot of attention due to their ability to enhance photovoltaic and photocatalytic processes via plasmonic effects. Thus far, most of the proposed heterostructures are designed with noble metals and the potential of alternative plasmonic materials, such as titanium nitride (TiN), is not yet well explored. In this work, TiN@TiO2 core–shell nanoparticles (NPs) are synthesized and proposed as plasmon‐enhanced photosensitizers for efficient singlet oxygen generation, with the focus on the role of hot electron injection. Excitation of dilute TiN@TiO2 NP dispersions by a 700 nm femtosecond‐pulsed laser effectively converts ground‐state oxygen into singlet oxygen (1O2), driven primarily by hot electrons generated during plasmon decay at the TiN–TiO2 interface and injected into the TiO2 layer. Analytical calculations reveal the unique advantages of TiN–TiO2 heterostructures in hot‐electron‐mediated photocatalysis. Considering the chemical inertness and low cost of TiN, TiN@TiO2 NPs hold great potential as plasmonic photosensitizers for photodynamic therapy and other photocatalytic applications at red‐to‐near‐infrared wavelengths. 相似文献
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Nan Gao Qiushi Huang Lingjian Zhang Mengluan Gao Yusheng Chen Rujia Zou 《Particle & Particle Systems Characterization》2023,40(12):2300097
Cancer is a serious threat to human life. However, the effect of single treatment method is limited at present. Here, a Cu2SnTe3 (CST) nano-reagent which can provide a strong synergetic effect in tumor therapy is successfully constructed. CST nanoparticles can not only convert endogenous H2O2 into ∙OH through surface-catalyzed reactions, but also generate 1O2 based on light irradiation-induced electron pair separation, leading to excessive oxidative stress accumulation in tumor cells. Interestingly, CST nanoparticles are also found to possess catalase-like activity, which enhances the level of O2 within hypoxic tumors, further improving the production efficiency of 1O2 by photodynamic therapy (PDT). In addition, the CST nanoparticles exhibit good photothermal conversion, which facilitates to promote more ∙OH production by chemodynamic therapy (CDT). The results of in vitro and in vivo anti-tumor experiments both demonstrate that CST nanoparticles can effectively inhibit the growth of tumor with minimal side effects. To sum up, CST nanoparticles have great potential in tumor treatment for efficient synergetic CDT/PDT/photothermal therapy. 相似文献
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Lifetimes of TPPS4 (meso-tetraphenylporphine tetrasulfonate) triplet states were measured for liquid solutions of different acidity and viscosity and as a function of acceptor concentration for different acceptors (bovine serum albumin, tryptophan and furfuryl alcohol). Triplet lifetimes were estimated by monitoring the decay of TPPS4 delayed fluorescence of E-type. The lifetime of delayed fluorencence depends on the concentration of O2, since the latter is an effective quencher of the triplet state. The lifetime is shown to be influenced mainly by degree of aggregation state of TPPS4 and, therefore, by the pH of the solution, decreasing with pH and for each pH remaining constant over a wide range of acceptor concentrations. The monomeric species is found to have the longest triplet lifetime in aqueous phosphate-buffered saline solution at neutral pH, especially when bound to albumin, despite of the low viscosity and protonated nature of the medium. 相似文献
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Although photodynamic therapy is an efficient therapeutic strategy for cancer treatment, it always suffers from the low singlet oxygen (1O2) yields owing to the weak absorption in optical transparent window of biological tissues. Herein, the black phosphorus (BP) nanosheet is integrated with gold nanoparticles (AuNPs) to simultaneously enhance the singlet oxygen generation and hyperthermia by localized surface plasmon resonance (LSPR) in cancer therapy. In the design, BP nanosheet employed as two‐dimension (2D) inorganic photosensitizer is hybridized with AuNPs through polyetherimide (PEI) as bridge to form BP‐PEI/AuNPs hybrid nanosheet. Such hybridation not only significantly increases the 1O2 production of BP nanosheet through maximizing the local field enhancement of AuNPs, but also significantly enhances the light absorption of BP nanosheet to promote photothermal effect by LSPR. Accordingly, about 3.9‐fold enhancement of 1O2 production and 1.7‐fold increasement of photothermal conversion efficiency are achieved compared with BP‐PEI alone upon single 670 nm laser irradiation. As a proof‐of‐concept model, BP‐PEI/AuNPs hybrid nanosheet with simultaneous dual‐modal phototherapy functions result in effective suppression of tumor growth with minimized side effects both in vitro and in vivo, indicating the great potential of the BP‐PEI/AuNPs hybrid nanosheet as an effective strategy to enhance the cancer therapy efficiency. 相似文献
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Xiaojun Yu Xing Tang Jingkang He Xuan Yi Guiying Xu Longlong Tian Rui Zhou Chen Zhang Kai Yang 《Particle & Particle Systems Characterization》2017,34(2)
Combination of different therapeutic strategies to treat cancer has attracted tremendous attention in recent years. Herein, the authors develop polydopamine (PDA) nanoparticles with polyethylene glycol (PEG) modification as a multifunctional nanocarrier for coloading photosensitizer chlorine6 (Ce6) and curcumin (Cur) for combined photodynamic therapy (PDT) and radiotherapy (RT) of cancer. PEGylated PDA nanoparticles (PDA‐PEG) exhibit well water soluble and biocompatible in different physiological solutions and cause no obvious toxicity to cancer cells. In this nanoparticle, the loaded Ce6 can trigger the generation of single oxygen under near‐infrared laser irradiation for PDT, while the loaded Cur can act as an excellent radiosensitizer under X‐ray irradiation for enhanced external RT. As demonstrated by in vitro and in vivo therapeutic efficiency, combined PDT and RT based on PDA‐PEG/Cur/Ce6 nanoparticles exhibits significant inhibition the growth of cancer cells, revealing perfect performance in cancer treatment. Therefore, the study not only presents a polymer‐based theranostic platform for cancer treatment but also demonstrates the potential applications of combined RT and PDT for the future clinic cancer therapy. 相似文献
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碳点作为一种新型碳纳米材料,具有优异的光学特性、良好的生物相容性以及催化活性,在生物医学、能源、环境等领域展现出巨大的应用潜力。红光/近红外光响应碳点具有组织穿透深度大、生物体自发光干扰较小、对组织损伤小等优点,在生物医学研究领域倍受关注。本文首先介绍了影响碳点吸收/发光的因素,随后评述了近几年红光/近红外光响应碳点在肿瘤治疗中的新进展,主要包括光动力治疗、光热治疗、光动力/光热协同治疗等。同时,针对肿瘤微环境的特点,介绍了微环境响应型碳点及其在肿瘤治疗中的应用研究进展。最后,对碳点在肿瘤治疗领域存在的挑战进行了展望。 相似文献
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The research in the field of the photodynamic therapy of cancer (PDT) is focused on a development of photosensitizers exhibiting high quantum yield of singlet oxygen production. Direct time-resolved spectroscopic observation of singlet oxygen phosphorescence can provide time constants of its population and depopulation as well as photosensitizer phosphorescence lifetime and relative quantum yields. In our contribution, a study of time and spectral resolved phosphorescence of singlet oxygen photosensitized by meso-tetraphenylporphine in acetone together with the photosensitizer phosphorescence is presented. Time constants of singlet oxygen population and depopulation were determined at wide range of photosensitizer concentrations. The time constant of singlet oxygen generation (0.28 ± 0.01) s is slightly shorter then the lifetime of photosensitizer's triplet state (0.32 ± 0.01) s. It is caused by lower ability of TPP aggregates to transfer excitation energy to oxygen. The lifetime of singlet oxygen (50 s) decreases with increasing photosensitizer concentration. Therefore, the photosensitizer acts also as a quencher of oxygen singlet state, similarly to the effects observed in [A. A. Krasnovsky, P. Cheng, R. E. Blankenship, T. A. Moore, and D. Gust (1993). Photochem. Photobiol.
57, 324–330; H. Küpper, R. Ddic, A. Svoboda, J. Hála, and P. M. H. Kroneck (2002). Biochim. Biophys. Acta Gen. Subj.
1572, 107–113]. Moreover, the increasing concentraion of the photosensitizer causes a slight hypsochromic shift of the singlet oxygen luminescence maximum. 相似文献
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Jiaojiao Sun Yuming Guo Lin Zhu Lin Yang Weike Shi Kui Wang Hua Zhang 《Particle & Particle Systems Characterization》2017,34(10)
Currently, the studies about photodynamic therapy (PDT) of human cancers have made considerable progress and attracted tremendous attention. The existing photosensitizers used for PDT are mainly organic compounds. In order to enhance their photosensitizing efficacy, some studies reported hybrid photosensitizers consisting of inorganic quantum dots (QDs) and organic photosensitizers. Herein, a new type of photosensitizer consisting of sole semiconductor CdTe QDs with good photosensitizing efficacy, excellent water dispersibility, and stability is reported. The photosensitizer is prepared through a facile one‐step strategy using sodium hyaluronate as a stabilizing and targeting agent. Different from most of the previous reports, the as‐prepared QDs do not show inhibition effects on normal cells in the experimental concentration range, but can also be directly utilized as a photosensitizer to specifically and remarkably inhibit the proliferation of human hepatoma cells. Mechanism studies reveal that the QDs could be specifically internalized by hepatoma cells, considerably induce the generation of intracellular reactive oxidative species under light illumination, and significantly induce the necrosis of hepatoma cells. This work provides an inspiration for the direct application of QDs as a new type of photosensitizer to specifically and significantly treat human hepatoma through PDT. 相似文献