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Nanoparticle PEGylation for imaging and therapy

    Jesse V Jokerst

    Molecular Imaging Program at Stanford (MIPS), Department of Radiology, 318 Campus Drive, Stanford University, Stanford, CA 94305-5427 USA

    ,
    Tatsiana Lobovkina

    Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305-5080 USA

    ,
    Richard N Zare

    Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA 94305-5080 USA

    Bioengineering, Materials Science & Engineering, Bio-Xc, Stanford University, Stanford, CA 94305, USA

    &
    Published Online:https://doi.org/10.2217/nnm.11.19

    Nanoparticles are an essential component in the emerging field of nanomedical imaging and therapy. When deployed in vivo, these materials are typically protected from the immune system by polyethylene glycol (PEG). A wide variety of strategies to coat and characterize nanoparticles with PEG has established important trends on PEG size, shape, density, loading level, molecular weight, charge and purification. Strategies to incorporate targeting ligands are also prevalent. This article presents a background to investigators new to stealth nanoparticles, and suggests some key considerations needed prior to designing a nanoparticle PEGylation protocol and characterizing the performance features of the product.

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