title: Development and comparative anti-microbial evaluation of lipid nanoparticles and nanoemulsion of Polymyxin B.
abstract: Polymyxin B is a decapeptide, mainly used for the treatment of gram-negative bacteremia. It was anticipated that a prolongation of release may lead to a more efficacious therapy. Lipid nanoparticles and nanoemulsion were formulated and comparatively evaluated for their properties. Lipid nanoparticles of Polymyxin B Sulphate with a mean particle size of 186.9 nm (Polydispersity Index 0.235) were prepared by nano-precipitation technique and nanoemulsion was prepared under the conditions of spontaneous formation with a mean globule size 125.0 nm (Polydispersity Index 0.291). The lipid nanoparticles were screened for lipid load from 0.1-1% along with 1-10% surfactant while in the optimization of nanoemulsion different ratios of oil, surfactant, and co-surfactant were evaluated. The developed systems were taken up for comparative anti-microbial study against a sensitive strain of E. coil using Turbidimetry as the method for monitoring the growth of microorganisms in a time dependent manner. Results of the study using ANOVA revealed an initial comparable activity with no statistical difference between the free drug, lipid nanoparticles, and the nanoemulsion. The anti-microbial effect was significantly sustained by lipid nanoparticles over a period of 18 hr but could not be sustained in case of nanoemulsion after 12 hr. Further, in order to assess anti-microbial activity of the developed delivery templates, a similar study was carried out using the lipid nanoparticles and nanoemulsion without the incorporation of drug. The results showed only a mild anti-microbial action for drug-free lipid nanoparticles but significant activity was exerted by drug-free nanoemulsion against plain drug throughout the study. It was concluded that the developed lipid nanoparticles and nanoemulsion are promising delivery vectors for the anti-microbial drugs. Further, lipid nanoparticles could give an initial as well as sustained effect while the nanoemulsion was capable of exerting potent effect for a shorter period of time.
authors.affiliation: Department of Pharmaceutical Sciences and Technology, University Institute of Chemical Technology, Mumbai 400019, India.
authors.forename: A S
authors.initials: AS
authors.lastname: Pattani
authors.forename: S D
authors.initials: SD
authors.lastname: Mandawgade
authors.forename: Vandana B
authors.initials: VB
authors.lastname: Patravale
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000737:chemistry; D002470:Cell Survival / Q000187:drug effects; D004337:Drug Carriers / Q000737:chemistry*; D004655:Emulsions; D004926:Escherichia coli / Q000166:cytology / Q000187:drug effects*; D008055:Lipids / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011112:Polymyxin B / Q000008:administration & dosage* / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D004337:Drug Carriers; D004655:Emulsions; D008055:Lipids; D008081:Liposomes; D011112:Polymyxin B