Abstract
Photodynamic antimicrobial chemotherapy (PACT) is considered a promising alternative to conventional antibiotic approach. We have previously developed a novel PS containing five lysine amino acids, pentalysine-β-carbonylphthalocyanine Zinc (ZnPc(Lys)(5)), which in the presence of light, is highly toxic against a range of bacterial strains, including hospital isolated, drug resistant Acinetobacter baumannii. Here, we study the effect of light fluence of the two light sources on the PACT potency of ZnPc(Lys)(5). We observed that an exposure of E.coli to a red LED light for only 2 seconds (light fluence of 0.15 J/cm(2)) in the presence of ZnPc(Lys)(5) significantly eradicated 80% of the E.coli. We further demonstrated that a light fluence of 4.5 J/cm(2) from a household light source induced a noticeable photodynamic effect in vitro and in vivo animal model. This study points to a new research direction of reducing light illumination time by increasing potency of PS.