Eradication of E. coli using synergistic eosin loaded metallocatanionic vesicle formulation in presence of visible light

This report aims to offer insight into the synergistic catanionic vesicle formulation using cationic metallosurfactant and its role in antibacterial photodynamic therapy (aPDT). For the preapartion of Metallocatanionic vesicles (MCVs) cationic double -chain Fe metallosurfactant (FeC II) was chosen in combination with single -chain anionic surfactant sodium oleate (Ol). The PDT ability of this formulation was assessed using anionic eosin (EON) as a Photosensitizer (PS). These vesicles were prepared by solution -solution mixing method and their formation was authenticated using zeta-sizer, field emission scanning electron microscope, and cryo- transmission electron microscope. These dual charged vesicles loaded with anionic eosin were further characterized using confocal microscopy. 9, 10-Anthracenediyl-bis(methylene) dimalonic acid assay evaluated the singlet oxygen generation ability of EON in the presence of MCVs. The cationic metalsurfactant-rich FeC II:Ol (7:3) fraction enhanced the singlet oxygen generation for anionic EON dye which also showed the significance of the metal ion's role in singlet oxygen enhancement. aPDT study confirmed that empty FeC II:Ol vesicles carry antibacterial properties that further enhances on light irradiation. Presently, multi -drug resistance to various bacteria is a serious concern in the modern world and aPDT is a fast-growing alternative technique. Thus, optimizing a newer formulation that is prepared from a noninvasive method, cost effective, uses water a solvent i.e. greener in approach and most importantly incorporate a well known PS Eosin (EON)is highly desired. The outcome of the present work is really encouraging as results revealed that both cationic rich and anionic rich fractions were active against E. coli,