Fig. 1

Preparation and characterization of the NPs. A Synthetic route of the PUA polymer. B DLS size distribution and C zeta potential of the PUA NPs. and C PUA NPs@RES. D Representative TEM images of the PUA NPs@RES. Scale bar = 200 nm. E DLS size distribution and F zeta potential of the PUA NPs@RES. G The particle size changes of PUA NPs and PUA NPs@RES in different media for 7 days H Representative images of red blood cells after treatment with various concentrations of PUA NPs@RES, water (positive), and saline solution (negative). I Quantitative analysis of hemolysis ratio. J In vitro drug release profiles of PUA NPs@RES in media with different pH values