In the current study, we synthesized a new SiPc derivative conjugated with arginine at the axial positions, for a novel phthalocyanine-based photosensitizer for photodynamic therapy (PDT) applications in cancer cells. Axially-di-arginine substituted new silicon(IV) phthalocyanine photosensitizer (PS-5a) has been thoroughly researched for its anti-cancer properties. Various spectroscopic techniques were used to characterize this conjugate, including 1H NMR, 13C NMR, FT-IR, UV-vis, and MS spectral data. The in vitro PDT activities of the conjugate on cancer cells were tested through its cytotoxic, clonogenic, apoptotic effects on, and its capacity to induce DNA damage, and the disruption of mitochondrial membrane potential in cancer cell lines (liver; HuH-7, cervix; HeLa and breast; MCF7). Cancer cells exposed to the light illumination following uptake of the PS-5a as a photosensitizer revealed DNA breakage and collapsed mitochondrial membrane potential. The results of the present investigation demonstrate that PS-5a has a significant photo-cytotoxic effect on cancer cells. So, axially-di-arginine substituted silicon(IV) phthalocyanine could be an effective PDT agent for PDT treatment.

Photodynamic therapy is a highly specific and clinically approved method in which a non-toxic photosensitizer drug is administered to the patient for cancer treatment. Phthalocyanines with their long wavelength absorption and fluorescence from 650 to 800 nm can be used as photosensitizers for photodynamic therapy and are used in clinical trials. In this study, functional novel axially substituted silicon (IV) phthalocyanine (PS-2) was synthesized. Unsubstituted dichlorosilicon (IV) phthalocyanine was synthesized from 1,3-diiminoisoindoline via cyclotetramerization. The axial substitution reaction was carried out using dichlorosilicon (IV) phthalocyanine and excess of N-Boc-ethanolamine. Structural characterization of this novel PS-2 by FT-IR, mass, 1H NMR and UV-Vis spectroscopy were performed. Photochemical properties (photo degradation quantum yields (d) and singlet oxygen quantum yield () of PS-2, which are the first steps for cancer treatment, were investigated.

A simple and efficient synthesis of novel zinc(II) phthalocyanines bearing triazole moieties was described. The synthetic approach for preparation of the phthalocyanines 1 and 13 was achieved by Schiff base condensation reaction of phthalocyanine tetracarbaldehydes 3 and 12 with 4-amino-4H-1,2,4-triazole 5 in tetrahydrofuran in reasonable yields. The photophysical and photochemical properties of the compounds 1, 3, 12 and 13 were recorded only in DMSO. The singlet oxygen generation ability of the targeted phthalocyanine Schiff bases were investigated in an attempt to understand their potential for photodynamic therapy (PDT) activity. Moreover, in vitro PDT application was performed against the MCF-7 and MDA-MB-231 invasive breast carcinoma cell lines. Preliminary assay showed that the compounds 1 and 13 possessed the phototoxicity and cytotoxicity, with a maximum of 30% MCF-7 cells dead following light irradiation. It was also revealed that the targeted phthalocyanines possess promising characteristic as photosensitizer towards tumor cells.

The phthalocyanines were synthesized via phthalonitrile cyclotetramerization in the presence of lithium metal and/or zinc acetate in this study. New symmetric peripheral-tetra and non-peripheral-tetra substituted phthalocyanines were substituted with N-Boc-ethanolamine. All newly synthesized phthalocyanines and starting materials were characterized by spectroscopic methods such as FT-IR, MALDI-TOF, 1H-NMR and UV–vis. Non-peripheral (3, 5, 5′) and peripheral (4, 4′, 6) phthalocyanine derivatives were determined aggregation, photophysical properties (such as fluorescence quantum yields and lifetimes) and photochemical properties (such as singlet oxygen generation and photostability) in dimethylsulfoxide (DMSO).

Used as photosensitizer in photodynamic therapy, phthalocyanines exhibit their long wavelength absorption and the ability to produce high singlet oxygen for tumor destruction with 650 to 800 nm fluorescence.Phthalocyanines with their long wavelength absorption and fluorescence from 650 to 800 nm exhibit their ability to produce high singlet oxygen for the destruction of tumors. In this study, new axial substituted silicon(IV) phthalocyanine (4) was synthesized. Unsubstituted dichlorosilicon phthalocyanine was synthesized from 1,3-diiminoisoindoline via cyclotetramerization. The axial substitution reaction was carried out using dichlorosilicon(IV) phthalocyanine and excess of 2-methoxyethanol. Structural characterization of this new axial-substituted silicon(IV) phthalocyanine by IR, mass, and UV-Vis spectroscopy were performed. Photochemical properties were investigated for cancer therapy. In this study, we found that axial substituted silicon(IV) phthalocyanine (4) may be promising PDT agent.

Mesoporous organosilica nanoparticles (PHT-PMO) have been prepared from an octa-triethoxysilylated Zn phthalocyanine precursor. These PHT-PMO nanoparticles had no dark toxicity but high phototoxicity when irradiated at 650 nm, and remarkable near-infrared phototoxicity when excited at 760 and 810 nm. The PHT-PMO were then aminated to promote electrostatic complexation with siRNA. Transfection experiments were performed upon NIR irradiation and photochemical internalization was very efficient, leading to 65% luciferase extinction in MCF-7 cancer cells expressing stable luciferase.

In line with current efforts to direct PDT photosensitizers to specific organelles such as mitochondria, a triphenylphosphonium-tetrasubstituted Zn phthalocyanine was designed, taking into account synthetic constraints. Triphenylphosphonium moieties were successfully introduced on alkyl bromide substituents on a pre-formed phthalocyanine. Photophysical and photochemical measurements showed that the photoproperties of the Zn phthalocyanine core were not affected by the triphenylphosphonium groups. Biological investigations demonstrated the dark innocuousness of the phthalocyanine up to 1 [Formula: see text]M, a concentration that exhibited a powerful phototoxicity. Cell death was confirmed to be photodynamically induced thanks to reactive oxygen species detection experiments. Nonetheless, the triphenylphosphonium moieties did not promote the accumulation of the phthalocyanine in mitochondria as significantly as expected.

Two structural factors (sulfonyl vs sulfanyl, 4,5- vs 3,6- position) of phthalonitriles - which are used in several material-related applications - have been comparatively investigated in terms of crystallographic properties and Hirshfeld surface analyses. The unexpected FT-IR spectra of the sulfonyl-substituted derivatives have been supported by DFT calculations.

Photosensitizing nanogels were obtained through a surfactant-free single-step protocol by using a porphyrin-based cross-linker for stabilizing self-assembled nanosized aggregates of thermoresponsive copolymers. Nanogels with varying amounts of porphyrin retained the singlet oxygen generation ability of the porphyrin core and were also capable of inducing temperature increase upon irradiation at 635 nm. Photoinduced killing efficiency was tested against three cell lines: human breast adenocarcinoma (MDA-MB-231 and MCF7) and pancreatic adenocarcinoma (AsPC-1) cells, and a predominant photodynamic mechanism at 450 nm and a mixed photodynamic and photothermal effect at 635 nm was observed. This innovative access to photosensitizing nanogels is a proof of concept, and opens new perspectives toward the preparation of optimized nanophotosensitizers.

Three bisphthalonitriles with different grafting functions (O/S/SO2) have been selected for their future interest in the preparation of dimeric phthalocyanines with tailored properties. The bisphthalonitrile derivatives have been prepared and comparatively characterized. Their complete structural properties were investigated and their XRD-determined structures were compared with their DFT-optimized ones. Molecular orbital levels and energy gaps were also determined and analysed. The sulfonyl (SO2) function induces different behaviour compared to the S and O grafting which are more similar.

Phthalonitriles are key precursors of phthalocyanines. Self-quenching dimeric phthalocyanines likely to be cleaved into monomeric species are of potential interest for tumour-site activated photosensitisers. Disulfide linkers can be specifically cleaved in tumoral tissue do to their reductive nature. Hence, a disulfide-linked phthalonitrile was designed to serve as further precursor of specifically tumour-activatable phthalocyanine-based photosensitising systems. Bisphthalonitrile with a disulfide-based linker and its dimethylene analogue were comparatively analyzed on a spectroscopic point of view as well as with DFT calculations. A thorough crystallographic analysis of the disulfide-linked derivative was conducted.