'Aggregation Induced Emission + Excited State Intramolecular Proton Transfer (AIE + ESIPT)'-assisted photorelease of an anticancer drug by a p-hydroxyphenacyl (pHP) phototrigger with real-time monitoring has been demonstrated.
View Article and Find Full Text PDFACS Appl Mater Interfaces
August 2017
Remedial cancer therapy deals with a large number of theranostic applications. However, systems, so far known, are only capable of single surveillance for both diagnostic and therapeutic modes of action. A nanosystem, which can be localized to the cancer and deliver the chemotherapeutic agent on demand, will provide effective therapeutic activity.
View Article and Find Full Text PDFCorrection for 'A spiropyran-coumarin platform: an environment sensitive photoresponsive drug delivery system for efficient cancer therapy' by Shrabani Barman et al., J. Mater.
View Article and Find Full Text PDFIn spite of inventing several anticancer agents the clinical payoff still remains unsatisfactory because of their severe host toxicity due to their nonspecific biodistribution in the body. To achieve high efficiency in anti-cancer drug delivery, thus, we designed and developed a single component photoresponsive drug delivery system, a fusion of two platforms spiropyran and coumarin, which synchronizes two controlling factors: first, the lower pH of cancer tissue, which acts as an internal control and leads to the ring opening of spiropyran resulting in a distinct colour change and fluorescence activation of coumarin; and second, the release of the anti-tumor drug by the externally controlled light. Highly fluorescent nature and promising biocompatibility make the SP-Cou-Cbl system suitable for cell imaging and in vitro studies.
View Article and Find Full Text PDFNanocarrier-mediated photodynamic therapy (PDT) is an effective tool for anti-tumour treatment due to the targeted and image-guided delivery of photosensitizers (PSs) to diseased tissues. These nanocarriers range from inorganic, ceramic, polymeric to biological nanoparticles (NPs). Such PS-grafted bicomponent nanocarriers have limitations like (i) difficulty in surface modification, (ii) lower loading percentages of the therapeutic agent, (iii) unstable physical encapsulation, etc.
View Article and Find Full Text PDFAmong the well-known phototriggers, the p-hydroxyphenacyl (pHP) group has consistently enabled the very fast, efficient, and high-conversion release of active molecules. Despite this unique behavior, the pHP group has been ignored as a delivery agent, particularly in the area of theranostics, because of two major limitations: Its excitation wavelength is below 400 nm, and it is nonfluorescent. We have overcome these limitations by incorporating a 2-(2'-hydroxyphenyl)benzothiazole (HBT) appendage capable of rapid excited-state intramolecular proton transfer (ESIPT).
View Article and Find Full Text PDFWe have developed an ESIPT based drug delivery system (DDS), Cou-Benz-Cbl conjugate, by incorporating a benzothiazole group at the 8th position of the 7-hydroxy-coumarin moiety for pH sensitive fluorescence properties and photocontrolled release of the anticancer drug chlorambucil. The Cou-Benz-Cbl conjugate exhibited unique photophysical properties like good absorbance at around 350 nm, a large Stokes shift (∼151 nm) and pH sensitive fluorescence properties. The pH sensitive fluorescence properties of the Cou-Benz-Cbl conjugate can be ascribed to an ESIPT turn "on and off" mechanism.
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