Mantareva, VanyaGöl, CemKussovski, VesselinDurmuş, MahmutAngelov, Ivan2021-06-232021-06-2320190939-50751865-7125https://doi.org/10.1515/znc-2018-0203https://hdl.handle.net/20.500.12491/9988The photodynamic impact of water-soluble zwitterionic zinc phthalocyanines (ZnPc1-4) was studied on pathogenic bacterial strains after specific light exposure (LED 665 nm). The structural differences between the studied ZnPc1-4 are in the positions and the numbers of substitution groups as well as in the bridging atoms (sulfur or oxygen) between substituents and macrocycle. The three peripherally substituted compounds (ZnPc1-3) are tetra-2-(N-propanesulfonic acid) oxypyridine (ZnPc1), tetra-2-( N-propanesulfonic acid) mercaptopyridine (ZnPc2), and octa-substituted 2-(N-propanesulfonic acid) mercaptopyridine (ZnPc3). The nonperipherally substituted compound is tetra-2-(N-propanesulfonic acid) mercaptopyridine (ZnPc4). The uptake and localization capability are studied on Gram (+) Enterococcus faecalis and Gram (-) Pseudomonas aeruginosa as suspensions and as 48 h biofilms. Relatively high accumulations of ZnPc1-4 show bacteria in suspensions with different cell density. The compounds have complete penetration in E. faecalis biofilms but with nonhomogenous distribution in P. aeruginosa biomass. The cytotoxicity test (Balb/c 3T3 Neutral Red Uptake) with ZnPc1-4 suggests the lack of dark toxicity on normal cells. However, only ZnPc3 has a minimal photocytotoxic effect toward Balb/c 3T3 cells and a comparable high potential in the photoinactivation of pathogenic bacterial species.eninfo:eu-repo/semantics/closedAccessFluorescence ImagesPathogenic BacteriaPhotodynamic Therapywater-soluble zwitterionic Zn(II) phthalocyaninesArticle10.1515/znc-2018-0203747-8183191311946952-s2.0-85067478502Q3WOS:000474398300003Q4