ARC Centre of Excellence in Convergent Bio-Nano Science & Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia.
Applied Functional Polymers, Macromolecular Chemistry I, University of Bayreuth, 95440, Bayreuth, Germany.
Macromol Rapid Commun. 2019 May;40(10):e1800911. doi: 10.1002/marc.201800911. Epub 2019 Feb 12.
Brush polymers are highly functional polymeric materials combining the properties of different polymer classes and have found numerous applications, for example, in nanomedicine. Here, the synthesis of functional phosphonate-ester-bearing brush polymers based on poly(2-oxazine)s is reported through a combination of cationic ring-opening polymerization (CROP) of 2-ethyl-2-oxazine and reversible addition-fragmentation chain transfer (RAFT) polymerization. In this way, a small library of well-defined (Đ ≤ 1.17) poly(oligo(2-ethyl-2-oxazine) methacrylate) P(OEtOzMA) brushes with tunable lower critical solution temperature (LCST) behavior and negligible cell toxicity is prepared. Upon deprotection, the phosphonic acid end-group of the P(OEtOzMA) brush enables the successful grafting-onto iron oxide nanoparticles (IONPs). Colloidal stability of the particle suspension in combination with suitable magnetic resonance imaging (MRI) relaxivities demonstrates the potential of these particles for future applications as negative MRI contrast agents.
刷状聚合物是高度功能化的聚合物材料，结合了不同聚合物类别的特性，在纳米医学等领域有广泛的应用。本文通过阳离子开环聚合（CROP）和可逆加成-断裂链转移（RAFT）聚合，合成了基于聚（2-恶唑啉）的功能化膦酸酯刷状聚合物。通过这种方法，制备了具有可调下临界溶液温度（LCST）行为和可忽略的细胞毒性的小分子量的（Đ ≤ 1.17）聚[低聚（2-乙基-2-恶唑啉）甲基丙烯酸酯] P（OEtOzMA）刷状聚合物。通过脱保护，P（OEtOzMA）刷的磷酸末端基团能够成功接枝到氧化铁纳米粒子（IONPs）上。胶体稳定性和合适的磁共振成像（MRI）弛豫率表明，这些粒子具有作为负性 MRI 造影剂的应用潜力。
