The Experts below are selected from a list of 16179 Experts worldwide ranked by ideXlab platform
Yong Zhang - One of the best experts on this subject based on the ideXlab platform.
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in vivo photodynamic therapy using upconversion nanoparticles as remote controlled nanotransducers
Nature Medicine, 2012Co-Authors: Niagara Muhammad Idris, Ratha Mahendran, Muthu Kumara Gnanasammandhan, Jing Zhang, Yong ZhangAbstract:Conventional photodynamic therapy (PDT) is limited by the penetration depth of visible light needed for its activation. Here we used mesoporous-silica-coated upconversion fluorescent nanoparticles (UCNs) as a nanotransducer to convert deeply penetrating near-infrared light to visible wavelengths and a carrier of Photosensitizers. We also used the multicolor-emission capability of the UCNs at a single excitation wavelength for simultaneous activation of two Photosensitizers for enhanced PDT. We showed a greater PDT efficacy with the dual-photosensitizer approach compared to approaches using a single photosensitizer, as determined by enhanced generation of singlet oxygen and reduced cell viability. In vivo studies also showed tumor growth inhibition in PDT-treated mice by direct injection of UCNs into melanoma tumors or intravenous injection of UCNs conjugated with a tumor-targeting agent into tumor-bearing mice. As the first demonstration, to the best of our knowledge, of the photosensitizer-loaded UCN as an in vivo-targeted PDT agent, this finding may serve as a platform for future noninvasive deep-cancer therapy.
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mesoporous silica coated up conversion fluorescent nanoparticles for photodynamic therapy
Small, 2009Co-Authors: Haisheng Qian, Ratha Mahendran, Paul C Ho, Yong ZhangAbstract:Near-infrared (NIR)-to-visible up-conversion fluorescent nanoparticles have potential to be used for photodynamic therapy (PDT) in deep tissue because NIR light can penetrate thick tissue due to weak absorption in the optical window. Here a uniform layer of mesoporous silica is coated onto NaYF4 up-converting nanocrystals, with a large surface area of ≈770 m2 g−1 and an average pore size of 2 nm. A photosensitizer, zinc phthalocyanine, is incorporated into the mesoporous silica. Upon excitation by a NIR laser, the nanocrystals convert NIR light to visible light, which further activates the photosensitizer to release reactive singlet oxygen to kill cancer cells. The photosensitizer encapsulated in mesoporous silica is protected from degradation in the harsh biological environment. It is demonstrated that the Photosensitizers loaded into the porous silica shell of the nanoparticles are not released out of the silica while they continuously produce singlet oxygen upon excitation by a NIR laser. The nanoparticles are reusable as the Photosensitizers encapsulated in the silica are removed by soaking in ethanol.
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mesoporous silica coated up conversion fluorescent nanoparticles for photodynamic therapy
Small, 2009Co-Authors: Haisheng Qian, Ratha Mahendran, Hui Chen Guo, Yong ZhangAbstract:Near-infrared (NIR)-to-visible up-conversion fluorescent nanoparticles have potential to be used for photodynamic therapy (PDT) in deep tissue because NIR light can penetrate thick tissue due to weak absorption in the optical window. Here a uniform layer of mesoporous silica is coated onto NaYF(4) up-converting nanocrystals, with a large surface area of approximately 770 m(2) g(-1) and an average pore size of 2 nm. A photosensitizer, zinc phthalocyanine, is incorporated into the mesoporous silica. Upon excitation by a NIR laser, the nanocrystals convert NIR light to visible light, which further activates the photosensitizer to release reactive singlet oxygen to kill cancer cells. The photosensitizer encapsulated in mesoporous silica is protected from degradation in the harsh biological environment. It is demonstrated that the Photosensitizers loaded into the porous silica shell of the nanoparticles are not released out of the silica while they continuously produce singlet oxygen upon excitation by a NIR laser. The nanoparticles are reusable as the Photosensitizers encapsulated in the silica are removed by soaking in ethanol.
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nanoparticles in photodynamic therapy an emerging paradigm
Advanced Drug Delivery Reviews, 2008Co-Authors: Dev K Chatterjee, Li Shan Fong, Yong ZhangAbstract:Abstract Photodynamic therapy (PDT) has emerged as one of the important therapeutic options in management of cancer and other diseases [M. Triesscheijn, P. Baas, J.H. Schellens, F.A. Stewart, Photodynamic therapy in oncology, Oncologist 11 (2006) 1034–1044]. Most Photosensitizers are highly hydrophobic and require delivery systems. Previous classification of delivery systems was based on presence or absence of a targeting molecule on the surface [Y.N. Konan, R. Gurny, E. Allemann, State of the art in the delivery of Photosensitizers for photodynamic therapy, J. Photochem. Photobiol., B 66 (2002) 89–106]. Recent reports have described carrier nanoparticles with additional active complementary and supplementary roles in PDT. We introduce a functional classification for nanoparticles in PDT to divide them into passive carriers and active participants in photosensitizer excitation. Active nanoparticles are distinguished from non-biodegradable carriers with extraneous functions, and sub-classified mechanistically into photosensitizer nanoparticles, [A.C. Samia, X. Chen, C. Burda, Semiconductor quantum dots for photodynamic therapy, J. Am. Chem. Soc. 125 (2003) 15736–15737, R. Bakalova, H. Ohba, Z. Zhelev, M. Ishikawa, Y. Baba, Quantum dots as Photosensitizers? Nat. Biotechnol. 22 (2004) 1360–1361] self-illuminating nanoparticles [W. Chen, J. Zhang, Using nanoparticles to enable simultaneous radiation and photodynamic therapies for cancer treatment, J. Nanosci. Nanotechnology 6 (2006) 1159–1166] and upconverting nanoparticles [P. Zhang, W. Steelant, M. Kumar, M. Scholfield, Versatile Photosensitizers for photodynamic therapy at infrared excitation, J. Am. Chem. Soc. 129 (2007) 4526–4527]. Although several challenges remain before they can be adopted for clinical use, these active or second-generation PDT nanoparticles probably offer the best hope for extending the reach of PDT to regions deep in the body.
Ilya Yakavets - One of the best experts on this subject based on the ideXlab platform.
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Optical properties of photodynamic therapy drugs in different environments: the paradigmatic case of temoporfin
Physical Chemistry Chemical Physics, 2020Co-Authors: Busenur Aslanoglu, Ilya Yakavets, Vladimir Zorin, Henri-pierre Lassalle, Francesca Ingrosso, Antonio Monari, Saron CatakAbstract:Computational tools have been used to study the photophysical and photochemical features of Photosensitizers in photodynamic therapy (PDT) – a minimally invasive, less aggressive alternative for cancer treatment. PDT is mainly based on the activation of molecular oxygen through the action of a photoexcited sensitizer (photosensitizer). Temoporfin, widely known as mTHPC, is a second-generation photosensitizer, which produces the cytotoxic singlet oxygen when irradiated with visible light and hence destroys tumor cells. However, the bioavailability of the mostly hydrophobic photosensitizer, and hence its incorporation into cells, is fundamental to achieve the desired effect on malignant tissues via PDT. In this study, we focus on the optical properties of the temoporfin chromophore in different environments – in vacuo, in solution, encapsulated in drug delivery agents, namely cyclodextrin, and interacting with a lipid bilayer.
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Current state of the nanoscale delivery systems for temoporfin-based photodynamic therapy: Advanced delivery strategies
Journal of Controlled Release, 2019Co-Authors: Ilya Yakavets, Vladimir Zorin, Henri-pierre Lassalle, Marie Millard, Lina BezdetnayaAbstract:Enthusiasm for photodynamic therapy (PDT) as a promising technique to eradicate various cancers has increased exponentially in recent decades. The majority of clinically approved Photosensitizers are hydrophobic in nature, thus, the effective delivery of Photosensitizers at the targeted site is the main hurdle associated with PDT. Temoporfin (mTHPC, medicinal product name: Foscan®), is one of the most potent clinically approved Photosensitizers, is not an exception. Successful temoporfin-PDT requires nanoscale delivery systems for selective delivery of photosensitizer. Over the last 25 years, the number of papers on nanoplatforms developed for mTHPC delivery such as conjugates, host-guest inclusion complexes, lipid-and polymer-based nanoparticles and carbon nanotubes is burgeoning. However, none of them appeared to be “ultimate”. The present review offers the description of different challenges and achievements in nanoparticle-based mTHPC delivery focusing on the synergetic combination of various nano-platforms to improve temoporfin delivery at all stages of biodistribution. Furthermore, the association of different nanoparticles in one nanoplatform might be considered as an advanced strategy allowing the combination of several treatment modalities.
Lina Bezdetnaya - One of the best experts on this subject based on the ideXlab platform.
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Current state of the nanoscale delivery systems for temoporfin-based photodynamic therapy: Advanced delivery strategies
Journal of Controlled Release, 2019Co-Authors: Ilya Yakavets, Vladimir Zorin, Henri-pierre Lassalle, Marie Millard, Lina BezdetnayaAbstract:Enthusiasm for photodynamic therapy (PDT) as a promising technique to eradicate various cancers has increased exponentially in recent decades. The majority of clinically approved Photosensitizers are hydrophobic in nature, thus, the effective delivery of Photosensitizers at the targeted site is the main hurdle associated with PDT. Temoporfin (mTHPC, medicinal product name: Foscan®), is one of the most potent clinically approved Photosensitizers, is not an exception. Successful temoporfin-PDT requires nanoscale delivery systems for selective delivery of photosensitizer. Over the last 25 years, the number of papers on nanoplatforms developed for mTHPC delivery such as conjugates, host-guest inclusion complexes, lipid-and polymer-based nanoparticles and carbon nanotubes is burgeoning. However, none of them appeared to be “ultimate”. The present review offers the description of different challenges and achievements in nanoparticle-based mTHPC delivery focusing on the synergetic combination of various nano-platforms to improve temoporfin delivery at all stages of biodistribution. Furthermore, the association of different nanoparticles in one nanoplatform might be considered as an advanced strategy allowing the combination of several treatment modalities.
Jianzhang Zhao - One of the best experts on this subject based on the ideXlab platform.
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enhancing photodynamic therapy through resonance energy transfer constructed near infrared photosensitized nanoparticles
Advanced Materials, 2017Co-Authors: Ling Huang, Yang Zhao, Jinyi Yang, Yucheng Yang, Aarushi Iris Pendharkar, Yuanwei Zhang, Sharon Kelmar, Liyong Chen, Jianzhang ZhaoAbstract:Photodynamic therapy (PDT) is an important cancer treatment modality due to its minimally invasive nature. However, the efficiency of existing PDT drug molecules in the deep-tissue-penetrable near-infrared (NIR) region has been the major hurdle that has hindered further development and clinical usage of PDT. Thus, herein a strategy is presented to utilize a resonance energy transfer (RET) mechanism to construct a novel dyad photosensitizer which is able to dramatically boost NIR photon utility and enhance singlet oxygen generation. In this work, the energy donor moiety (distyryl-BODIPY) is connected to a photosensitizer (i.e., diiodo-distyryl-BODIPY) to form a dyad molecule (RET-BDP). The resulting RET-BDP shows significantly enhanced absorption and singlet oxygen efficiency relative to that of the acceptor moiety of the photosensitizer alone in the NIR range. After being encapsulated with biodegradable copolymer pluronic F-127-folic acid (F-127-FA), RET-BDP molecules can form uniform and small organic nanoparticles that are water soluble and tumor targetable. Used in conjunction with an exceptionally low-power NIR LED light irradiation (10 mW cm−2), these nanoparticles show superior tumor-targeted therapeutic PDT effects against cancer cells both in vitro and in vivo relative to unmodified Photosensitizers. This study offers a new method to expand the options for designing NIR-absorbing Photosensitizers for future clinical cancer treatments.
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styryl bodipy c60 dyads as efficient heavy atom free organic triplet Photosensitizers
Organic Letters, 2012Co-Authors: Ling Huang, Jianzhang ZhaoAbstract:C60-styryl Bodipy dyads that show strong absorption of visible light (e = 64 600 M–1 cm–1 at 657 nm) and a long-lived triplet excited state (τT = 123.2 μs) are prepared. The dyads were used as heavy-atom-free organic triplet Photosensitizers for photooxidation of 1,5-dihydroxynaphthalene via the photosensitizing of singlet oxygen (1O2). The photooxidation efficiency of the dyads compared to the conventional Ir(III) complex 1O2 photosensitizer increased 19-fold.
Henri-pierre Lassalle - One of the best experts on this subject based on the ideXlab platform.
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Optical properties of photodynamic therapy drugs in different environments: the paradigmatic case of temoporfin
Physical Chemistry Chemical Physics, 2020Co-Authors: Busenur Aslanoglu, Ilya Yakavets, Vladimir Zorin, Henri-pierre Lassalle, Francesca Ingrosso, Antonio Monari, Saron CatakAbstract:Computational tools have been used to study the photophysical and photochemical features of Photosensitizers in photodynamic therapy (PDT) – a minimally invasive, less aggressive alternative for cancer treatment. PDT is mainly based on the activation of molecular oxygen through the action of a photoexcited sensitizer (photosensitizer). Temoporfin, widely known as mTHPC, is a second-generation photosensitizer, which produces the cytotoxic singlet oxygen when irradiated with visible light and hence destroys tumor cells. However, the bioavailability of the mostly hydrophobic photosensitizer, and hence its incorporation into cells, is fundamental to achieve the desired effect on malignant tissues via PDT. In this study, we focus on the optical properties of the temoporfin chromophore in different environments – in vacuo, in solution, encapsulated in drug delivery agents, namely cyclodextrin, and interacting with a lipid bilayer.
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Current state of the nanoscale delivery systems for temoporfin-based photodynamic therapy: Advanced delivery strategies
Journal of Controlled Release, 2019Co-Authors: Ilya Yakavets, Vladimir Zorin, Henri-pierre Lassalle, Marie Millard, Lina BezdetnayaAbstract:Enthusiasm for photodynamic therapy (PDT) as a promising technique to eradicate various cancers has increased exponentially in recent decades. The majority of clinically approved Photosensitizers are hydrophobic in nature, thus, the effective delivery of Photosensitizers at the targeted site is the main hurdle associated with PDT. Temoporfin (mTHPC, medicinal product name: Foscan®), is one of the most potent clinically approved Photosensitizers, is not an exception. Successful temoporfin-PDT requires nanoscale delivery systems for selective delivery of photosensitizer. Over the last 25 years, the number of papers on nanoplatforms developed for mTHPC delivery such as conjugates, host-guest inclusion complexes, lipid-and polymer-based nanoparticles and carbon nanotubes is burgeoning. However, none of them appeared to be “ultimate”. The present review offers the description of different challenges and achievements in nanoparticle-based mTHPC delivery focusing on the synergetic combination of various nano-platforms to improve temoporfin delivery at all stages of biodistribution. Furthermore, the association of different nanoparticles in one nanoplatform might be considered as an advanced strategy allowing the combination of several treatment modalities.
