Fig. 2. Percentage doxorubicin release from Au@PEG-INU/Doxo NPs over time, when stored in PBS solutions at pH 7.4 and pH 5.5. Doxorubicin not associated with NPs, both in the free base (–NH₂) and hydrochloride forms, were used to determine normal doxorubicin release during dialysis.