Red-Shifted Environmental Fluorophores and Their Use for the Detection of Gram-Negative Bacteria

Two novel, water-soluble, merocyanine fluorophores were readily prepared by microwave-assisted synthesis. Full optical characterization was performed in a series of protic and aprotic solvents, the dyes displayed fluorescence red region with up to 20-fold decrease brightness water, demonstrating strong environmental sensitivity hereby termed as solvato-fluorogenicity (to distinguish from solvatochromism). Shorter fluorescent lifetimes also measured which confirmed this character. These conjugated modified polymyxin scaffold that allowed “switch-on” upon binding Gram-negative bacterial membranes, selective detection bacteria wash-free protocol.