Poly(ethylene glycol)-block-poly(aspartate-hydrazide) (PEG-p(Asp-Hyd)) was modified using either levulinic acid (LEV) or 4-acetyl benzoic acid (4AB) attached via hydrazone bonds. Paclitaxel (PTX) conjugated to the linkers formed PEG-p(Asp-Hyd-LEV-PTX) and PEG-p(Asp-Hyd-4AB-PTX). PEG-p(Asp-Hyd-LEV-PTX) and PEG-p(Asp-Hyd-4AB-PTX) assemble into unimodal polymeric micelles with diameters of 42 nm and 137 nm, respectively. PEG-p(Asp-Hyd-LEV-PTX) and PEG-p(Asp-Hyd-4AB-PTX) at...