title: Lipid and polymer nanoparticles for drug delivery to bacterial biofilms.
abstract: Biofilms are matrix-enclosed communities of bacteria that show increased antibiotic resistance and the capability to evade the immune system. They can cause recalcitrant infections which cannot be cured with classical antibiotic therapy. Drug delivery by lipid or polymer nanoparticles is considered a promising strategy for overcoming biofilm resistance. These particles are able to improve the delivery of antibiotics to the bacterial cells, thereby increasing the efficacy of the treatment. In this review we give an overview of the types of polymer and lipid nanoparticles that have been developed for this purpose. The antimicrobial activity of nanoparticle encapsulated antibiotics compared to the activity of the free antibiotic is discussed in detail. In addition, targeting and triggered drug release strategies to further improve the antimicrobial activity are reviewed. Finally, ample attention is given to advanced microscopy methods that shed light on the behavior of nanoparticles inside biofilms, allowing further optimization of the nanoformulations. Lipid and polymer nanoparticles were found to increase the antimicrobial efficacy in many cases. Strategies such as the use of fusogenic liposomes, targeting of the nanoparticles and triggered release of the antimicrobial agent ensured the delivery of the antimicrobial agent in close proximity of the bacterial cells, maximizing the exposure of the biofilm to the antimicrobial agent. The majority of the discussed papers still present data on the in vitro anti-biofilm activity of nanoformulations, indicating that there is an urgent need for more in vivo studies in this field.
authors.affiliation: Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium; Center for Nano- and Biophotonics, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: Forier
authors.affiliation: Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Koen
authors.initials: K
authors.lastname: Raemdonck
authors.affiliation: Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Stefaan C
authors.initials: SC
authors.lastname: De Smedt
authors.affiliation: Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: Demeester
authors.affiliation: Laboratory of Pharmaceutical Microbiology, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Tom
authors.initials: T
authors.lastname: Coenye
authors.affiliation: Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium; Center for Nano- and Biophotonics, Harelbekestraat 72, 9000 Ghent, Belgium. Electronic address: Kevin.Braeckmans@ugent.be.
authors.forename: Kevin
authors.initials: K
authors.lastname: Braeckmans
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001419:Bacteria; D001424:Bacterial Infections / Q000188:drug therapy*; D018441:Biofilms; D003692:Delayed-Action Preparations; D004337:Drug Carriers / Q000737:chemistry*; D006801:Humans; D008081:Liposomes; D053758:Nanoparticles / Q000737:chemistry*; D011108:Polymers
chemical_list: D000900:Anti-Bacterial Agents; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D008081:Liposomes; D011108:Polymers
keywords: Antibiotics; Biofilm; Drug delivery; Liposome; Nanomedicines; Polymer nanoparticles