Arginine mediated photodynamic therapy with silicon(IV) phthalocyanine photosensitizers

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.

Synthesis of near-infrared-responsive hexagonal-phase upconversion nanoparticles with controllable shape and luminescence efficiency for theranostic applications

Over the past few decades, photodynamic therapy has been studied as a therapeutic method by generating singlet oxygen through activation of a photosensitizer (PS) to kill cancer cells. However, the light within the activating wavelength range of commercial photosensitizers has a low penetration depth. In this study, we designed multifunctional upconversion nanoparticles (UCNs) that can emit high-energy light by absorbing low-energy near-infrared (NIR) light with excellent tissue permeability through a fluorescence resonance energy transfer procedure. This process can produce reactive oxygen species by activating the PS. We aimed to optimize the thermal decomposition synthesis procedure to produce lanthanide-doped UCNs with a uniform size and improve the photoluminescence efficiency for an NIR-regulated theranostic system. It was confirmed that the morphologies of UCNs can be controlled by varying the reaction time, reaction temperature, and feed molar ratio of the solvent and reactant. The crystalline morphology of the synthesized UCNs showed a thermodynamically stable hexagonal phase. The photoluminescence efficiency of the UCNs also was influenced by size, surface area, crystalline property, and stability in aqueous solution. Furthermore, the surface-modified UCNs with a folic acid-conjugated block copolymer and PS exhibited enhanced singlet oxygen generation and significantly improved aqueous solubility and photoluminescence efficiency.

Improved targeting for photodynamic therapy via a biotin–phthalocyanine conjugate: synthesis, photophysical and photochemical measurements, and in vitro cytotoxicity assay

In this study, the peripherally biotin-substituted zinc(ii) phthalocyanine (Pc2) was synthesized as a photosensitizer for the treatment of cancer by photodynamic therapy.

Dual-directional alkyne-terminated macrocycles: Enroute to non-aggregating molecular platforms

Derivatized phthalocyanines (Pcs) and their heteroatom analogues, azaphthalocyanines (AzaPcs), bearing a variety of highly active ligands, have many advantageous properties that make them suitable as novel macrocyclic platforms.

Photobiological characteristics of chlorophyll a derivatives as microbial PDT agents

Chlorin-e6 (chl-e6) and a hydrogenated derivative (chl-e6H) were semi-synthesized, and their photophysical properties and photodynamic activity againstEscherichia coli,Staphylococcus aureusandCandida albicansevaluated.