pH/redox dual-responsive nanogels (DEX-SS) were prepared by precipitation polymerization ofmethacrylated dextran (DEXMA), 2-aminoethylmethacrylate (AEMA) and N,N0-bis(acryloyl)cystamine(BAC), and then loaded with methotrexate (MTX). Nanogels were spherical and exhibited homogeneoussize distribution (460 nm, PDI < 0.30) as observed using dynamic light scattering (DLS) and scanning electronmicroscopy (SEM). DEX-SS were sensitive to the variations of pH and redox environment. Nanogelsincubated in buffer pH 5.0 containing 10 mM glutathione (GSH) synergistically increased the mean diameterand the PDI to 750 nm and 0.42, respectively. In vitro release experiments were performed at pH 7.4and 5.0 with and without GSH. The cumulative release of MTX in pH 5.0 medium with 10 mM GSH was 5-fold higher than that recorded at pH 7.4 without GSH. Fibroblasts and tumor cells were used to tests theeffects of blank DEX-SS and MTX@DEX-SS nanogels on cell viability. Remarkable influence of pH on nanogelsinternalization into HeLa cells was evidenced by means of confocal microscopy and flow cytometry
pH/redox dual-sensitive dextran nanogels for enhanced intracellular drug delivery
Curcio M.;Cirillo G.;Iemma F.;
2017-01-01
Abstract
pH/redox dual-responsive nanogels (DEX-SS) were prepared by precipitation polymerization ofmethacrylated dextran (DEXMA), 2-aminoethylmethacrylate (AEMA) and N,N0-bis(acryloyl)cystamine(BAC), and then loaded with methotrexate (MTX). Nanogels were spherical and exhibited homogeneoussize distribution (460 nm, PDI < 0.30) as observed using dynamic light scattering (DLS) and scanning electronmicroscopy (SEM). DEX-SS were sensitive to the variations of pH and redox environment. Nanogelsincubated in buffer pH 5.0 containing 10 mM glutathione (GSH) synergistically increased the mean diameterand the PDI to 750 nm and 0.42, respectively. In vitro release experiments were performed at pH 7.4and 5.0 with and without GSH. The cumulative release of MTX in pH 5.0 medium with 10 mM GSH was 5-fold higher than that recorded at pH 7.4 without GSH. Fibroblasts and tumor cells were used to tests theeffects of blank DEX-SS and MTX@DEX-SS nanogels on cell viability. Remarkable influence of pH on nanogelsinternalization into HeLa cells was evidenced by means of confocal microscopy and flow cytometryI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
