Poster AA12 - Ultrashort pulsed laser-coupled surface scanning systems for broad-spectrum clinical disinfection

Introduction: As novel and drug-resistant pathogens threaten the rise of a post-antibiotic era, alternative antimicrobial strategies are urgently needed. We previously discovered that visible ultrashort pulsed (USP) lasers operating under certain parameters could inactivate a wide range of microorganisms such as viruses, bacteria (including multidrug-resistant strains and spores), fungi, and mycoplasma via an impulsive stimulated Raman scattering mechanism, without overt toxicity to mammalian cells. Recently we developed a USP laser-coupled two-dimensional scanning device for clinically-directed surface treatment applications.

Materials and

Methods: Aqueous samples of Zika virus, Escherichia coli 25922 bacteria, HEK-293F human embryonic kidney cells, and BL10 primary mouse stem cells on model surfaces were irradiated using this system at varying scan speeds. Standard focus-forming and colony-forming assays and trypan blue exclusion assays were used to determine viral, bacterial, and mammalian cell viabilities, respectively.

Results, Conclusions, and Discussions: The treatment achieved ~95.0% (1.3-log) reductions in viral titer and ≥99.9% (3-log) reductions in bacterial cell counts while preserving ~99.0% and ~88.6% human and mouse cell viability, respectively relative to controls. Further optimization and investigation of the effects of USP laser treatment in different cell types and tissues may establish USP lasers as a method for universal and selective disinfection of skin wounds, mucosal surfaces, cell lines, and other biological entities.

Acknowledgements (Optional): We would like to thank Spencer Cassady and Jeresia Henson for their administrative support.