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Stimuli-responsive smart nanogels for cancer diagnostics and therapy

    Motoi Oishi

    Tsukuba Interdisciplinary Materials Science (TIMS), University of Tsukuba, 1–1-1 Tennoudai, Tsukuba, Ibaraki 305-8573, Japan.

    Center for Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Japan

    Graduate School of Pure and Applied Sciences, University of Tsukuba, Japan

    &
    Yukio Nagasaki

    † Author for correspondence

    Tsukuba Interdisciplinary Materials Science (TIMS), University of Tsukuba, 1–1-1 Tennoudai, Tsukuba, Ibaraki 305-8573, Japan.

    Center for Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Japan

    Graduate School of Pure and Applied Sciences, University of Tsukuba, Japan

    Master’s School of Medical Sciences, University of Tsukuba, Japan

    International Center for Materials Nanoarchitectonics Satellite (MANA), National Institute for Materials Science (NIMS) and University of Tsukuba, Japan

    Published Online:https://doi.org/10.2217/nnm.10.18

    This article discusses stimuli-responsive poly(ethylene glycol) (PEG)-coated (PEGylated) nanogels and their biomedical applications. Preparation and characterization of stimuli-responsive PEGylated nanogels composed of a crosslinked poly(2-[N,N-diethylamino]ethyl methacrylate) (PEAMA) core and PEG tethered chains are initially described. Stimuli-responsive PEGylated nanogels show unique properties and functions in synchronizing with the reversible volume phase transition of the PEAMA core in response to the extracellular pH (7–6.5) of a tumor environment as well as endosomal/lysosomal pH (6.5–5.0) and temperature. We list several biomedical applications of stimuli-responsive PEGylated nanogels, including 19F magnetic resonance spectroscopic imaging (MRS/I) probe to visualize acidosis (tumor tissue), intracellular drug and siRNA delivery, antennas for cancer photothermal therapy and apoptosis probe for monitoring response to cancer therapy. Thus, stimuli-responsive PEGylated nanogels can be utilized as smart nanomedicines for cancer diagnostics and therapy.

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