Interplay of phosphate and carbonate ions with flavin photosensitizers in photodynamic inactivation of bacteria.

Photodynamic inactivation (PDI) of pathogenic bacteria is a promising technology in different applications. Thereby, a photosensitizer (PS) absorbs visible light and transfers the energy to oxygen yielding reactive oxygen species (ROS). The produced ROS are then capable of killing microorganisms via oxidative damage of cellular constituents.

Black tattoos entail substantial uptake of genotoxicpolycyclic aromatic hydrocarbons (PAH) in human skin and regional lymph nodes.

Hundreds of millions of people worldwide have tattoos, which predominantly contain black inks consisting of soot products like Carbon Black or polycyclic aromatic hydrocarbons (PAH). We recently found up to 200 μg/g of PAH in commercial black inks. After skin tattooing, a substantial part of the ink and PAH should be transported to other anatomical sites like the regional lymph nodes.

Black tattoo inks are a source of problematic substances such as dibutyl phthalate.

Background: Tattooing has recently become increasingly popular. Using tiny needles, tattooists place the tattoo ink in the dermis along with numerous unknown ingredients. Most tattoos consist of black inks, which are predominantly composed of soot products (carbon black with polycyclic aromatic hydrocarbons).

The decrease of pigment concentration in red tattooed skin years after tattooing.

Background: Tattooing entails the injection of high amounts of colourants into skin. Excepting black inks, red azo pigments are the most frequent colourant used. Part of the pigment is transported away via lymphatic system.

Safety testing of indocyanine green with different surgical light sources and the protective effect of optical filters.

Purpose: The purpose of this study was to assess the light-induced cytotoxicity of indocyanine green (ICG) using different light sources commonly used in macular surgery and to assess the effect of optical filters.

Methods: Primary cultures of porcine retinal pigment epithelium cells were incubated with 0.5 mg/mL ICG solution dissolved in 5% glucose and illuminated with a surgical light fiber for 3 or 15 minutes.