Viral reduction of human blood by ultraviolet A-photosensitized vitamin K5.

Blood product transfusion can transmit viral pathogens. Pathogen reduction methods for blood products have been developed but, so far, are not available for whole blood. We evaluated if vitamin K5 (VK5) and ultraviolet A (UVA) irradiation could be used for virus inactivation in plasma and whole blood.

Synergistic bactericidal effects of pairs of photosensitizer molecules activated by ultraviolet A light against bacteria in plasma.

Background: The current approach to reducing bacterial contamination in blood transfusion products is through detection or pathogen reduction methods, some of which utilize ultraviolet (UV) light photosensitizers. A small number of photosensitizers are being used as single agents in combination with UV light, but their efficacy can be limited against some pathogens. Benzophenone (BP) and vitamins B1, B6, and K3 have been identified as effective UVA photosensitizers for inactivation of bacteria.

Inactivation of bacteria in plasma by photosensitizers benzophenone and vitamins K3, B1 and B6 with UV A light irradiation.

Background: A photosensitizer is a light-activated molecule that can generate reactive oxygen species or directly interact with nucleic acids. Both consequences can be applied to reduction of pathogens in various media and to selectively attack tumor cells. Numerous natural and synthesized photosensitizers have been identified for pathogen reduction.