Cyanoarylporphyrazines with High Viscosity Sensitivity: A Step towards Dosimetry-Assisted Photodynamic Cancer Treatment

Despite the significant relevance of photodynamic therapy (PDT) as an efficient strategy for primary and adjuvant anticancer treatment, several challenges compromise its efficiency. In order to develop an “ideal photosensitizer” and the requirements applied to photosensitizers for PDT, there is still a need for new photodynamic agents with improved photophysical and photobiological properties. In this study, we performed a detailed characterization of two tetracyanotetra(aryl)porphyrazine dyes with 4-biphenyl (pz II) and 4-diethylaminophenyl (pz IV) groups in the periphery of the porphyrazine macrocycle. Photophysical properties, namely, fluorescence quantum yield and lifetime of both photosensitizers, demonstrate extremely high dependence on the viscosity of the environment, which enables them to be used as viscosity sensors. PzII and pz IV easily enter cancer cells and efficiently induce cell death under light irradiation. Using fluorescence lifetime imaging microscopy, we demonstrated the possibility of assessing local intracellular viscosity and visualizing viscosity changes driven by PDT treatment with the compounds. Thus, pz II and pz IV combine the features of potent photodynamic agents and viscosity sensors. These data suggest that the unique properties of the compounds provide a tool for PDT dosimetry and tailoring the PDT treatment regimen to the individual characteristics of each patient.

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Characterization of thylakoid membrane in a heterocystous cyanobacterium and green alga with dual-detector fluorescence lifetime imaging microscopy with a systematic change of incident laser power

Biochimica et Biophysica Acta (BBA) - Bioenergetics ◽

10.1016/j.bbabio.2015.10.003 ◽

2016 ◽

Vol 1857 (1) ◽

pp. 46-59 ◽

Cited By ~ 8

Author(s):

Shuho Nozue ◽

Akira Mukuno ◽

Yumi Tsuda ◽

Takashi Shiina ◽

Masahide Terazima ◽

...

Keyword(s):

Laser Power ◽

Fluorescence Lifetime Imaging Microscopy ◽

Systematic Change ◽

Fluorescence Lifetime Imaging ◽

Incident Laser ◽

Heterocystous Cyanobacterium ◽

Lifetime Imaging ◽

Incident Laser Power ◽

Dual Detector

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ASDToolkit: A Novel MATLAB Processing Toolbox for ASD Field Spectroscopy Data

10.20944/preprints202008.0535.v1 ◽

2020 ◽

Author(s):

Kathryn Elmer ◽

Raymond Soffer ◽

J. Pablo Arroyo-Mora ◽

Margaret Kalacska

Keyword(s):

Individual Characteristics ◽

Atmospheric Conditions ◽

Current Effort ◽

Data Product ◽

Field Spectroscopy ◽

The Individual ◽

Solar Position ◽

Derived Data

Over the past 30 years, the use of field spectroscopy has risen in importance in remote sensing studies for the characterization of the surface reflectance of materials in situ within a broad range of applications. Potential uses range from measurements of individual targets of interest (e.g. vegetation, soils, validation targets etc.), to characterizing the contributions of different materials within larger spatially-mixed areas as would be representative of the spatial resolution captured by a sensor pixel (UAV to satellite scale). As such, it is essential that a complete and rigorous assessment of both the data-acquisition procedures, and the suitability of the derived data product be carried out. The measured energy from solar-reflected range spectroradiometers is influenced by the viewing and illumination geometries and the illumination conditions which vary due to changes in solar position and atmospheric conditions. By applying corrections, the estimated absolute reflectance (Rabs) of targets can be calculated. This property is independent of illumination intensity or conditions and is the metric commonly suggested to be used to compare spectra even when data are collected by different sensors or acquired under different conditions. By standardizing the process of estimated Rabs, as is provided in the described toolkit, consistency and repeatability in processing are ensured and the otherwise labor intensive and error-prone processing steps are streamlined. The resultant end data product (Rabs) represents our best current effort to generate consistent and comparable ground spectra which have been corrected for viewing and illumination geometries as well as other factors such as the individual characteristics of the reference panel used during acquisition.

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