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Graphene
Published in Pradipta Ranjan Rauta, Yugal Kishore Mohanta, Debasis Nayak, Nanotechnology in Biology and Medicine, 2019
Kunal Biswas, Debashis De, Jaya Bandyopadhyay
The fact that GO-IONP-PEG could be used as the T2 contrast agent for MRI application in mice with tumors in vivo was shown by Ma et al. (2012) for the first time. The aforesaid complex also proved to be beneficial while performing magnetic field–guided localized photothermal ablation of cancer cells, as the complex displays good optical density in the range of NIR to visible electromagnetic spectrum. These findings highlight the significance of biocompatible multifunctional graphene-based nanocomposites in cancer theranostics. In a separate study, Shen et al. (2012) combined PEG-functionalized GO complex with gadolinium-diethylenetriamine-pentaacetic acid–poly(diallyl dimethylammonium) chloride (Gd-DTPA-PDDA) to give rise to a multifunctional nanocomposite as an MRI probe. In order to make the conjugate more specific towards a tumor, FA (Huang et al., 2011) was used to modify the same, which was subsequently charged with DOX. The as-prepared GO-based multifunctional conjugate demonstrated outstanding therapeutic potential and efficient imaging towards tumor and freely available gadolinium cations (Gd3+) respectively. It was seen that a photosensitizer named chlorin e6 (Ce6), upon being loaded onto FA-functionalized GO, began to overaccumulate in tumor cells, causing better photodynamic efficacy when irradiated with electromagnetic rays (Huang et al., 2012). A multicomponent system comprising IONP (Fe3O4), fluorescent near-infrared probe cyanine 5.0 NHS (Cy5), and poly(amido amine) G4 dendrimer (PAMAM-64-NH2) was developed over the surface of GO by Wate et al. (2012) for imaging cells. The mechanism of cellular uptake by GO in gold–GO nanocomposite structures was investigated by Huang et al. via surface-enhanced Raman spectroscopy (SERS) (Huang et al., 2012).
Reduced Porphyrins as Photosensitizers: Synthesis and Biological Effects
Published in Barbara W. Henderson, Thomas J. Dougherty, Photodynamic Therapy, 2020
Photosensitization in vitro has also been shown for purpurin-18 46 and chlorin p647, two further derivatives of chlorophyll [52]. Cell killing was in part attributed to the amphipathic nature of these compounds in increasing cell uptake. Of further interest was the anhydride moiety of the purpurin that, it was claimed, could be used to form covalent attachments to nucleophiles, such as amino acids.
Performance of Pandannus amaryllifolius dye on zinc oxide nanoflakes synthesized via electrochemical anodization method
Published in Inorganic and Nano-Metal Chemistry, 2023
N. A. Asli, S. Z. Zainol, K. M. Yusoff, N. E. A. Azhar, M. Z. Nurfazianawatie, H. Omar, N. F. Rosman, N. S. A. Malek, R. Md Akhir, I. Buniyamin, Z. Khusaimi, M. F. Malek, N. D. Md Sin, M. Rusop
Several studies revealed that chlorophyll dyes are effective photosensitizers in photosynthesis and are potential environment-friendly dye sources.[17] The conversion efficiency of cells with chlorophyll derivatives as sensitizers is more than 2% and that of cells with chlorin-e6 reaches is more than 4%. Chlorophyll absorbs light from red, blue, and violet wavelengths and obtains its color by reflecting green. Therefore, this pigment is a suitable photosensitizer in the visible-light region. Chlorophyll is found in the leaves of most green plants, cyanobacteria, and algae. Hence, from an economic point of view, chlorophyll is the optimal dye sensitizer for fabrication of DSSCs because it can be extracted through simple processes.[14]
Synergistic photodynamic and photothermal therapy of BODIPY-conjugated hyaluronic acid nanoparticles
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Bowen Chen, Jie Cao, Kebiao Zhang, Yuan-Ning Zhang, Jiaju Lu, Muhammad Zubair Iqbal, Quan Zhang, Xiangdong Kong
To date, a variety of PSs have been reported including organic compounds (such as, organic dyes and conducting polymers) and inorganic nanomaterials (e.g. metal-based and carbon-based nanomaterials) [19–21]. Compared with inorganic nanomaterials, organic PSs have advantages of biodegradability and biocompatibility [22, 23]. Although various organic PSs, including porphyrin, chlorin e6 (Ce6), phthalocyanin, and boron dipyrromethene (BODIPY), have been developed to achieve tumor destruction upon light irradiation [5, 24–26], their therapeutic efficacy is often limited because of their poor solubility and low accumulation selectivity in tumor tissues [27–29]. To improve PSs bioavailability, many nanocarriers, including liposomes, polymeric nanoparticles, dendrimers, and inorganic nanomaterials, have been explored to increase the accumulation of PSs at tumor sites by taking advantage of the enhanced permeation and retention (EPR) effect [30–34].
Mechanochemical in situ generated gas reactant for the solvent-free hydrogenation of porphyrins
Published in Green Chemistry Letters and Reviews, 2021
Marta Pineiro, Carla Gomes, Mariana Peixoto
These hydrogenation reactions, which mostly use diimide as reducing agent and p-toluenesulfonylhydrazine as diimide source- based on the original method described by Whitlock (30) – suffer from several drawbacks: large excess of diimide source, large amounts of solvents and base, long reaction times or high temperature, reaction waste with large amounts of p-toluenesulfinic acid and the selectivity to chlorin is not easy to control. The most critical aspect is the control of the reaction conditions to obtain chlorin selectively, avoiding the synthesis of the related bacteriochlorin (tetrahydroporphyrin) through double hydrogenation at opposite pyrrole rings. Nevertheless, the selectivity can be improved by re-oxidation using MnO2 or hydrogen peroxide and iron trichloride as oxidant (31, 32).