title: Bacterial imaging and photodynamic inactivation using zinc(II)-dipicolylamine BODIPY conjugates.
abstract: Targeted imaging and antimicrobial photodynamic inactivation (PDI) are emerging methods for detecting and eradicating pathogenic microorganisms. This study describes two structurally related optical probes that are conjugates of a zinc(II)-dipicolylamine targeting unit and a BODIPY chromophore. One probe is a microbial targeted fluorescent imaging agent, mSeek, and the other is an oxygen photosensitizing analogue, mDestroy. The conjugates exhibited high fluorescence quantum yield and singlet oxygen production, respectively. Fluorescence imaging and detection studies examined four bacterial strains: E. coli, S. aureus, K. pneumonia, and B. thuringiensis vegetative cells and purified spores. The fluorescent probe, mSeek, is not phototoxic and enabled detection of all tested bacteria at concentrations of ∼100 CFU mL(-1) for B. thuringiensis spores, ∼1000 CFU mL(-1) for S. aureus and ∼10,000 CFU mL(-1) for E. coli. The photosensitizer analogue, mDestroy, inactivated 99-99.99% of bacterial samples and selectively killed bacterial cells in the presence of mammalian cells. However, mDestroy was ineffective against B. thuringiensis spores. Together, the results demonstrate a new two-probe strategy to optimize PDI of bacterial infection/contamination.
authors.affiliation: Department of Chemistry and Biochemistry, 236 Nieuwland Science Hall, University of Notre Dame, Notre Dame, 46556 IN, USA. smith.115@nd.edu.
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Rice
authors.forename: Haiying
authors.initials: H
authors.lastname: Gan
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Smith
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D001896:Boron Compounds / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D055668:Photochemical Processes; D017319:Photosensitizing Agents / Q000737:chemistry; D010847:Picolines / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D010848:Picolinic Acids / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D013171:Spores, Bacterial
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D000890:Anti-Infective Agents; D001896:Boron Compounds; D009942:Organometallic Compounds; D017319:Photosensitizing Agents; D010847:Picolines; D010848:Picolinic Acids; C509592:zinc(II) dipicolylamine