What is the most common photosensitizer used?

Although Photofrin is the most widely used photosensitizer in clinical PDT, it has several weaknesses (Berlanda et al., 2010; Ding et al., 2004; Triesscheijn et al., 2006).

What are photosensitizer drugs?

Photosensitizing agents are drugs that can make the skin more sensitive to UV radiation. Drug-induced phototoxic reactions generally present as unexpected sunburns or dermatitis on sun-exposed areas of the skin.

What are photosensitizers examples?

A commonly used sensitizer is mercury, which absorbs radiation at 1849 and 2537 angstroms; these are the wavelengths of light produced in high-intensity mercury lamps. Also used as sensitizers are cadmium; some of the noble gases, particularly xenon; zinc; benzophenone; and a large number of organic dyes.

What are photodynamic agents?

Background: Photodynamic therapy (PDT) is photo-treatment of malignant or benign diseases using photosensitizing agents, light, and oxygen which generates cytotoxic reactive oxygens and induces tumour regressions.

What is the best example of photosensitizer?

The resulting photoproducts are sometimes photosensitizers themselves. Perhaps the best known example is the formation of kynurenine from tryptophan. This is of clinical importance in cataract formation, where crosslinking between the crystallines in the lens has been shown to occur.

Which is photosensitizer?

Definition. Photosensitizers are molecules which absorb light (hν) and transfer the energy from the incident light into another nearby molecule. This light is often within the visible spectrum or infrared spectrum, as any higher energy electromagnetic radiation may result in the photoelectric effect.

What is Chlorin e6?

Chlorin e6 is a naturally occurring chlorin commonly used as a photosensitizer. Chlorin e6 has been examined as a nanotechnology delivery tool. Solubility : Soluble in DMSO.

What are the two types of photosensitizing reactions?

Photosensitized reactions involving oxygen are framed as either as type I or type II. Type I and II photosensitized oxidation reactions require oxygen as a reagent. The type I and II photosensitized mechanisms apply to photoreactions including initial electron or hydrogen atom abstraction as an oxidizing step.

What are the materials used in photodynamic therapy?

PDT applications involve three components: a photosensitizer, a light source and tissue oxygen. The wavelength of the light source needs to be appropriate for exciting the photosensitizer to produce radicals and/or reactive oxygen species.

What is a Chlorin ring?

: any of several derivatives of chlorophyll obtained by hydrolysis, removal of the magnesium, sometimes with replacement by another metal (as copper), and opening of the carbocyclic ring — see chlorophyllin sense 2.

Is Chlorin a porphyrin?

In organic chemistry, chlorins are tetrapyrrole pigments that are partially hydrogenated porphyrins. The parent chlorin is an unstable compound which undergoes air oxidation to porphine. The reduced chlorin variants are present in bacteriochlorophylls and are named ‘bacteriochlorins’ and ‘isobacteriochlorins’.

Which is an example of the use of photosensitizers?

One branch of chemistry which frequently utilizes photosensitizers is polymer chemistry, using photosensitizers in reactions such as photopolymerization, photocrosslinking, and photodegradation.

Are there any photosensitizers that are approved for PDT?

Photosensitizers that are in advanced stages of clinical trials or have been approved for anticancer PDT include chlorins, bacteriochlorins, benzoporphyrins, phthalocyanines, prophycenes, and hypericins (Agostinis et al., 2011; Juarranz et al., 2008; Palumbo, 2007).

What are the wavelengths of second generation photosensitizers?

Second-generation photosensitizers are usually activated with wavelengths above 650 nm and have less phototoxicity, since their clearance from normal tissues is much faster than for porphyrins (Bazylińska et al., 2012).

How does an exogenous photosensitizer reach the skin?

Exogenous photosensitizers may reach the skin by topical or systemic routes. Most photosensitizers are unsaturated tricyclic aromatic rings in linear arrangement, many have a lone pair of electrons not involved in bonding, and most are fluorescent.

What is the most common photosensitizer used? Although Photofrin is the most widely used photosensitizer in clinical PDT, it has several weaknesses (Berlanda et al., 2010; Ding et al., 2004; Triesscheijn et al., 2006). What are photosensitizer drugs? Photosensitizing agents are drugs that can make the skin more sensitive to UV radiation. Drug-induced phototoxic reactions…