Enhancing the Efficacy of Metal-Free MRI Contrast Agents via Conjugating Nitroxides onto PEGylated Cross-Linked Poly(Carboxylate Ester).

ABSTRACT: Herein, two water-soluble PROXYL-based magnetic resonance imaging (MRI) macromolecular organic contrast agents (mORCAs) are designed and synthesized: linear and cross-linked PCE-mPEG-Ppa-PROXYL. They are prepared by conjugating linear and cross-linked poly(carboxylate ester) (PCE) with poly(ethylene glycol) (mPEG₂₀₀₀)-modified nitroxides (PROXYL), respectively. Both mORCAs form self-assembled aggregates in an aqueous phase and PROXYL is protected inside a hydrophobic core to achieve great resistance to reduction in the physiological environment, and they have low toxicity. Since cross-linked PCE-mPEG-Ppa-PROXYL possess a branched architecture, its self-assembled aggregate is more stable and compact with a greater particle size. Cross-linked PCE-mPEG-Ppa-PROXYL outperform the lin

SUBMITTER: Guo S 

PROVIDER: S-EPMC7375229 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature