title: Synthesis of Photo- and pH Dual-Sensitive Amphiphilic Copolymer PEG43-b-P(AA76-co-NBA35-co-tBA9) and Its Micellization as Leakage-Free Drug Delivery System for UV-Triggered Intracellular Delivery of Doxorubicin.
abstract: Novel photo- and pH dual-sensitive amphiphilic copolymers containing photolabile o-nitrobenzyl (NB) groups were designed via combination of ATRP, hydrolyzation, and simple esterification reaction and self-assembled into stimuli-regulated amphiphilic micelles in aqueous solution. On the basis of the optimization of the morphology and particle size of the micelles via modulating the number of the photocleavable o-nitrobenzyl acrylate (NBA) units, the unique ones assembled from PEG43-b-P(AA76-co-NBA35-co-tBA9) with an average hydrodynamic diameter (Dh) of 163 nm was selected as a potential drug delivery system (DDS) for UV-triggered delivery of doxorubicin (DOX). The micelles possessed a favorable drug-loading capacity (DLC) of 27.5%, with the hydrodynamic diameter of 213 nm after DOX-loading. Most importantly, the DOX-loaded PEG43-b-P(AA76-co-NBA35-co-tBA9) micelles exhibited a cumulative DOX release ratio of only 3.69% in the simulated physiological medium within 6 days without UV-irradiation, indicating their potential as leakage-free DDS. As in the acidic media mimicking the tumor microenvironment, a high cumulative DOX release ratio of 74.70% was achieved within 6 days after UV-irradiation for 20 min, showing a sustained release behavior. Under UV-irradiation, the photolabile o-nitrobenzyl moieties were cleaved off, the amphiphilic copolymer transformed into a water-soluble polymer, favoring the metabolism of drug carriers, and the micelles were demicellized to accelerate the drug release in a triggered or on-demand manner.
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Xubo
authors: X
authors: Zhao
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Mingzhu
authors: M
authors: Qi
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Shuo
authors: S
authors: Liang
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Kun
authors: K
authors: Tian
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Tingting
authors: T
authors: Zhou
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Xu
authors: X
authors: Jia
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Jiagen
authors: J
authors: Li
authors: State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
authors: Peng
authors: P
authors: Liu
mesh_terms: D004317:Doxorubicin / Q000737:chemistry*; D004337:Drug Carriers; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D011108:Polymers
chemical_list: D004337:Drug Carriers; D008823:Micelles; D011108:Polymers; D004317:Doxorubicin
keywords: UV-triggered delivery; drug delivery system; leakage-free; micelle; photosensitive amphiphilic copolymer