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PubMed · 12922162

Surface-engineered nanoparticles for multiple ligand coupling.

Ruxandra Gref·Patrick Couvreur·Gillian Barratt·Evgueni Mysiakine
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Abstract

The design of surface-engineered nanoparticles for targeting to specific sites is a major challenge. To our knowledge, no study in the literature deals with ligand functionalization of biodegradable nanoparticles through biotin-avidin interactions. With the aim of conceiving small-sized nanoparticles which can be easily functionalized with a variety of ligands or mixtures thereof, biotinylated and PEGylated biotin-poly(ethylene glycol)-poly(epsilon-caprolactone) (B-PEG-PCL) copolymers were synthesized and used to prepare nanoparticles of around 100 nm. Avidin, followed by biotinylated wheat germ agglutinin as a model lectin, were coupled to their surface by taking advantage of the strong biotin-avidin complex formation. The cytotoxicity of the nanospheres towards Caco-2 cells in culture was negligible (more than 82% cell survival for nanoparticle concentrations up to 300 microg/well). The amount of radiolabeled poly(lactic acid) (PLA) or PEG-PLA nanoparticles associated with Caco-2 cells was only 0.7% and 1.5% of the amount added, respectively. This value was increased to 8.5% when a sufficient amount of lectin was bound to the PEG-PLA copolymer. After further studies, the biotin-PEG-coated nanoparticles could be helpful tools for studying the interaction between cells and functionalized nanoparticles with various surface characteristics (PEG layer density and thickness, ligand type and density).

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Binding SitesBiomimetic MaterialsCell Line, TumorCell SurvivalChromatography, GelEthylene OxideHumansIndicators and ReagentsLactonesLigandsMagnetic Resonance SpectroscopyModels, MolecularMolecular ConformationSurface PropertiesJournal Article

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Ruxandra Gref, Patrick Couvreur, Gillian Barratt, Evgueni Mysiakine. 2003. Surface-engineered nanoparticles for multiple ligand coupling.. https://doi.org/10.1016/s0142-9612(03)00348-x

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