Synthesis, photophysical studies and 1O2 generation of carboxylate-terminated zinc phthalocyanine dendrimers

PEG-containing ruthenium phthalocyanines as photosensitizers for photodynamic therapy: synthesis, characterization and in vitro evaluation

Three ruthenium(ii) phthalocyanines functionalized at their axial positions with 4-12 PEG chains bearing hydroxy, amino and ether terminal groups were synthesized and studied as PDT agents against bladder cancer cells. All three dyes displayed high singlet oxygen generation quantum yields in DMSO (Φ_Δ = 0.76). The water-soluble Ru(L3)₂Pc also shows high singlet oxygen quantum yields (Φ_Δ = 0.48) in neat water. In vitro studies show that these complexes are accumulated in bladder cancer cells, are nontoxic PSs per se, and have high phototoxic efficiency.

Water-soluble metalloporphyrinates with excellent photo-induced anticancer activity resulting from high tumor accumulation

To develop a water-soluble and tumor-targeted photosensitizer for photodynamic therapy (PDT), a porphyrin framework containing the metal ion gallium(III) was combined with platinum(II)-based groups to produce two new pentacationic metalloporphyrinates, Ga-4cisPtTPyP (5,10,15,20-tetrakis{cis-diammine-chloro-platinum(II)}(4-pyridyl)-porphyrinato gallium(III) hydroxide tetranitrate) and Ga-4transPtTPyP (5,10,15,20-tetrakis{trans-diammine-chloro-platinum(II)} (4-pyridyl)-porphyrinato gallium(III) hydroxide tetranitrate). Both complexes exhibited high singlet oxygen quantum yields (Φ_∆) and remarkable photocytotoxicity with appreciable phototoxic indexes (PIs). In particular, Ga-4cisPtTPyP showed a low IC₅₀ value (Colon 26: 0.12μM; Sarcoma 180: 0.08μM) under illumination and its PI up to 1000. With outstanding tumor accumulation (tumor/muscle ratio>9), Ga-4cisPtTPyP almost completely inhibited tumor growth over two weeks in an in vivo PDT assay. These results imply that Ga-4cisPtTPyP could be a promising anticancer agent for use in PDT.

Cationic phthalocyanine dendrimers as potential antimicrobial photosensitisers

Synthesis, photophysical properties and photoantimicrobial efficiency of cationic Zn(ii) and Ru(ii) dendrimeric phthalocyanines.

Dendrimeric Sulfanyl Porphyrazines: Synthesis, Physico-Chemical Characterization, and Biological Activity for Potential Applications in Photodynamic Therapy

Sulfanyl porphyrazines substituted at their periphery with different dendrimeric moieties up to their first generation were synthesized and characterized by photochemical and biological methods. The presence of a dendrimeric periphery enhanced the spectral properties of the porphyrazines studied. The singlet-oxygen-generation quantum yield of the obtained macrocycles ranged from 0.02 to 0.20 and was strongly dependent on the symmetry of the compounds and the terminal groups of the dendritic outer shell. The in vitro biological effects of three most promising tribenzoporphyrazines were examined; the results indicated their potential as photosensitizers for photodynamic therapy (PDT) against two oral squamous cell carcinoma cell lines derived from the tongue. The highest photocytotoxicity was found for sulfanyl tribenzoporphyrazine that possessed 4-[3,5-di(hydroxymethyl)phenoxy]butyl substituents with nanomolar IC₅₀ values at 10 and 42 nm against CAL 27 and HSC-3 cell lines, respectively.

Anionic hexadeca-carboxylate tetrapyrazinoporphyrazine: synthesis and in vitro photodynamic studies of a water-soluble, non-aggregating photosensitizer

Photodynamic activity of hexadeca-carboxylate tetrapyrazinoporphyrazine is largely influenced by intracellular pH and its interaction with serum proteins.

Protein cages and synthetic polymers: a fruitful symbiosis for drug delivery applications, bionanotechnology and materials science

Protein cages have become essential tools in bionanotechnology due to their well-defined, monodisperse, capsule-like structure. Combining them with synthetic polymers greatly expands their application, giving rise to novel nanomaterials fore.g.drug-delivery, sensing, electronic devices and for uses as nanoreactors.

Cholesteryl oleate-appended phthalocyanines as potential photosensitizers in the treatment of leishmaniasis

Two phthalocyanines (Pcs) with either a zinc or a ruthenium metal at the center of the macrocycle have been functionalized by a cholesteryl oleate moiety. The potential photosensitizers (PSs) for the treatment of cutaneous leishmaniasis have been studied on their photophysical properties and their ability to generate singlet oxygen. These experiments corroborate that solvent mixtures containing variable ratios of THF and water impact the excited state deactivation. The compounds were used preloaded into LDL particles and their phototoxic activity was evaluated in a preliminary way.

Generation-dependent templated self-assembly of biohybrid protein nanoparticles around photosensitizer dendrimers

In this article, we show the great potential of dendrimers for driving the self-assembly of biohybrid protein nanoparticles. Dendrimers are periodically branched macromolecules with a perfectly defined and monodisperse structure. Moreover, they allow the possibility to incorporate functional units at predetermined sites, either at their core, branches, or surface. On these bases, we have designed and synthesized negatively charged phthalocyanine (Pc) dendrimers that behave as photosensitizers for the activation of molecular oxygen into singlet oxygen, one of the main reactive species in photodynamic therapy (PDT). The number of surface negative charges depends on dendrimer generation, whereas Pc aggregation can be tuned through the appropriate choice of the Pc metal center and its availability for axial substitution. Remarkably, both parameters determine the outcome and efficiency of the templated self-assembly process by which a virus protein forms 18 nm virus-like particles around these dendritic chromophores. Protein-dendrimer biohybrid nanoparticles of potential interest for therapeutic delivery purposes are obtained in this way. Biohybrid assemblies of this kind will have a central role in future nanomedical and nanotechnology applications.