Impact of the hydrophilic-lipophilic balance of free-base and Zn(II) tricationic pyridiniumporphyrins and irradiation wavelength in PDT against the melanoma cell lines.

The amphiphilic and asymmetric structure of porphyrins, when used as photosensitizers (PSs) for photodynamic therapy (PDT), has been shown through numerous previous studies to be a very important property that facilitates their entry into cells, which improves their efficiency in PDT. In this work, two groups of cationic AB pyridiniumporphyrins, free-base and chelated with Zn(II), both substituted with alkyl chains of various lengths, were studied in PDT on melanoma cell lines. The aim was to investigate the impact of hydrophilic-lipophilic balance and Zn(II) chelation, and the importance of matching the irradiation wavelength to the optical properties of the PS on in vitro PDT efficiency.

Systemic Effects of Photoactivated 5,10,15,20-tetrakis(-methylpyridinium-3-yl) Porphyrin on Healthy .

Porphyrins are frequently employed in photodynamic therapy (PDT), a non-invasive technique primarily utilized to treat subcutaneous cancers, as photosensitizing agents (PAs). The development of a new PA with improved tissue selectivity and efficacy is crucial for expanding the application of PDT for the management of diverse cancers. We investigated the systemic effects of 5,10,15,20-tetrakis(-methylpyridinium-3-yl)-porphyrin (TMPyP3) using adult males.

Photodynamic inactivation of multidrug-resistant strains of Klebsiella pneumoniae and Pseudomonas aeruginosa in municipal wastewater by tetracationic porphyrin and violet-blue light: The impact of wastewater constituents.

There is an increasing need to discover effective methods for treating municipal wastewater and addressing the threat of multidrug-resistant (MDR) strains of bacteria spreading into the environment and drinking water. Photodynamic inactivation (PDI) that combines a photosensitiser and light in the presence of oxygen to generate singlet oxygen and other reactive species, which in turn react with a range of biomolecules, including the oxidation of bacterial genetic material, may be a way to stop the spread of antibiotic-resistant genes. The effect of 5,10,15,20-(pyridinium-3-yl)porphyrin tetrachloride (TMPyP3) without light, and after activation with violet-blue light (VBL) (394 nm; 20 mW/cm2), on MDR strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and K.

Combination of Two Photosensitisers in Anticancer, Antimicrobial and Upconversion Photodynamic Therapy.

Photodynamic therapy (PDT) is a special form of phototherapy in which oxygen is needed, in addition to light and a drug called a photosensitiser (PS), to create cytotoxic species that can destroy cancer cells and various pathogens. PDT is often used in combination with other antitumor and antimicrobial therapies to sensitise cells to other agents, minimise the risk of resistance and improve overall outcomes. Furthermore, the aim of combining two photosensitising agents in PDT is to overcome the shortcomings of the monotherapeutic approach and the limitations of individual agents, as well as to achieve synergistic or additive effects, which allows the administration of PSs in lower concentrations, consequently reducing dark toxicity and preventing skin photosensitivity.

Targeting Microenvironment of Melanoma and Head and Neck Cancers in Photodynamic Therapy.

Background: Photodynamic therapy (PDT), in comparison to other skin cancers, is still far less effective for melanoma, due to the strong absorbance and the role of melanin in cytoprotection. The tumour microenvironment (TME) has a significant role in tumour progression, and the hypoxic TME is one of the main reasons for melanoma progression to metastasis and its resistance to PDT. Hypoxia is also a feature of solid tumours in the head and neck region that indicates negative prognosis.

Photodynamic Inactivation of Biofilm Formation by Cationic Tetra- and Tripyridylporphyrins in Waters of Different Hardness.

The bacterium is still one of the probable causes of waterborne diseases, causing serious respiratory illnesses. In the aquatic systems, exists inside free-living amoebae or can form biofilms. Currently developed disinfection methods are not sufficient for complete eradication of biofilms in water systems of interest.

Cationic Porphyrins as Effective Agents in Photodynamic Inactivation of Opportunistic Plumbing Pathogen .

is an environmental bacterium, an opportunistic premise plumbing pathogen that causes the Legionnaires' disease. presents a serious health hazard in building water systems, due to its high resistance to standard water disinfection methods. Our aim was to study the use of photodynamic inactivation (PDI) against .

In Vitro Photodynamic Activity of N-Methylated and N-Oxidised Tripyridyl Porphyrins with Long Alkyl Chains and Their Inhibitory Activity in Sphingolipid Metabolism.

A series of N-methylated and N-oxidised tripyridyl porphyrins were synthesised, characterised, and their PDT activity was studied with six cell lines. All the tested porphyrins with a long alkyl chain, except one, were more efficient for PDT than an N-methylated hydrophilic porphyrin and N-oxidised porphyrin without the long alkyl chain. Generally, N-methylated tripyridyl porphyrins were more active than those N-oxidised, but IC values for phototoxicity of two N-oxides, named TOPyP3-C H O and TOPyP3-C H , were still in the nanomolar concentration range for most of the tested cell lines.