Dataset Information

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.

SUBMITTER: Rice DR

PROVIDER: S-EPMC4490101 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Bacterial imaging and photodynamic inactivation using zinc(II)-dipicolylamine BODIPY conjugates.

Rice Douglas R DR Gan Haiying H Smith Bradley D BD

Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 20150701 7

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 oxy ...[more]

PMID: 26063101

Similar Datasets

Project description:PurposeThis study prepared three structurally related zinc-dipicolylamine (ZnDPA) tracers with [(111)In] labels and conducted biodistribution and single-photon emission computed tomography/computed tomography (SPECT/CT) imaging studies of a mouse leg infection model.ProceduresTwo monovalent tracers, ZnDPA-[(111)In]DTPA and ZnDPA-[(111)In]DOTA, each with a single zinc-dipicolylamine targeting unit, and a divalent tracer, Bis(ZnDPA)-[(111)In]DTPA, with two zinc-dipicolylamine units were prepared. Organ biodistribution and SPECT and CT imaging studies were performed on living mice with a leg infection created by injection of clinically relevant Gram positive Streptococcus pyogenes. Fluorescent and luminescent Eu(3+)-labeled versions of these tracers were also prepared and used to measure relative affinity for the exterior membrane surface of bacterial cells and mimics of healthy mammalian cells.ResultsAll three (111)In-labeled radiotracers were prepared with a radiopurity of >90 %. The biodistribution studies showed that the two monovalent tracers were cleared from the body through the liver and kidney, with retained percentage injected dose for all organs of <8 % at 20 h and infected leg target to non-target ratio (T/NT) ratio of ≤3.0. Clearance of the divalent tracer from the bloodstream was slower and primarily through the liver, with a retained percentage injected dose for all organs <37 % at 20 h and T/NT ratio rising to 6.2 after 20 h. The SPECT/CT imaging indicated the same large difference in tracer pharmacokinetics and higher accumulation of the divalent tracer at the site of infection.ConclusionsAll three [(111)In]-ZnDPA tracers selectively targeted the site of a clinically relevant mouse infection model that could not be discerned by visual external inspection of the living animal. The highest target selectivity, observed with a divalent tracer equipped with two zinc-dipicolylamine targeting units, compares quite favorably with the imaging selectivities previously reported for other nuclear tracers that target bacterial cell surfaces. The tracer pharmacokinetics depended heavily on tracer molecular structure suggesting that it may be possible to rapidly fine tune the structural properties for optimized in vivo imaging performance and clinical translation.

Dataset Information

Bacterial imaging and photodynamic inactivation using zinc(II)-dipicolylamine BODIPY conjugates.

Publications

Bacterial imaging and photodynamic inactivation using zinc(II)-dipicolylamine BODIPY conjugates.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets