One pot preparation of polyurethane-based GSH-responsive core-shell nanogels for controlled drug delivery

In this work, we present a new type of glutathione (GSH)-responsive polyurethane-based core-shell nanogels (RS-CS-PUNGs) with hydrophilic methoxypolyethylene glycols (mPEG) shell, which was prepared by a one-pot synthetic method. The obtained RS-CSPUNGs not only show a good size distribution with the hydrodynamic radii around of 20 nm, but also exhibit good stability in the organic solvent. The results demonstrate that GSH (10 mM) trigger the nanogel swelling and accelerate the loaded drug release in PBS (pH = 7.4). Although the RS-CS-PUNGs loaded with DOX show a slower cellular uptake behavior than the free doxorubicin (DOX), which is likely caused by the controlled drug release property of the nanocarrier, the enhanced cellular uptake fluorescence intensity of RS-CS-PUNGs loaded with DOX is still observed compared to the control group. Both MTT and CCK-8 assay indicate that although an obvious lower initial cytotoxicity is observed compared to free DOX at 24 h postincubation, the cytotoxicity of the RS-CS-PUNGs loaded with DOX is obvious enhanced after treated 72 h, which stayed at the similar level with free DOX. Attributing to the easy preparation progress and GSH-responsive property, RS-CS-PUNGs maybe hold the potential for further application in the field of drug delivery. (c) 2019 Wiley Periodicals, Inc.