title: Targeted nanoparticles for enhanced X-ray radiation killing of multidrug-resistant bacteria.
abstract: This paper describes a nanoparticle enhanced X-ray irradiation based strategy that can be used to kill multidrug resistant (MDR) bacteria. In the proof-of-concept experiment using MDR Pseudomonas aeruginosa (P. aeruginosa) as an example, polyclonal antibody modified bismuth nanoparticles are introduced into bacterial culture to specifically target P. aeruginosa. After washing off uncombined bismuth nanoparticles, the bacteria are irradiated with X-rays, using a setup that mimics a deeply buried wound in humans. Results show that up to 90% of MDR P. aeruginosa are killed in the presence of 200 μg ml(-1) bismuth nanoparticles, whereas only ∼6% are killed in the absence of bismuth nanoparticles when exposed to 40 kVp X-rays for 10 min. The 200 μg ml(-1) bismuth nanoparticles enhance localized X-ray dose by 35 times higher than the control with no nanoparticles. In addition, no significant harmful effects on human cells (HeLa and MG-63 cells) have been observed with 200 μg ml(-1) bismuth nanoparticles and 10 min 40 kVp X-ray irradiation exposures, rendering the potential for future clinical use. Since X-rays can easily penetrate human tissues, this bactericidal strategy has the potential to be used in effectively killing deeply buried MDR bacteria in vivo.
authors.affiliation: Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Luo
authors.forename: Mainul
authors.initials: M
authors.lastname: Hossain
authors.forename: Chaoming
authors.initials: C
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Qiao
authors.forename: Jincui
authors.initials: J
authors.lastname: An
authors.forename: Liyuan
authors.initials: L
authors.lastname: Ma
authors.forename: Ming
authors.initials: M
authors.lastname: Su
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001729:Bismuth / Q000737:chemistry; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems; D004352:Drug Resistance, Microbial; D006367:HeLa Cells; D006801:Humans; D009010:Monte Carlo Method; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D011092:Polyethylene Glycols / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013499:Surface Properties; D014965:X-Rays
chemical_list: D000900:Anti-Bacterial Agents; D011092:Polyethylene Glycols; D001729:Bismuth