Dataset Information

PH-responsive superstructures prepared via the assembly of Fe3O4 amphipathic Janus nanoparticles.

ABSTRACT: The strategy of using Fe3O4 amphiphilic Janus nanoparticles (Fe3O4@AJNPs) bearing ?-cyclodextrin (?-CD) and aminopyridine (APD) functionalized polymethyl methacrylate (PGMA) to construct pH-stimuli responsive co-assemblies through host-guest interactions between ?-CD and APD was proposed. The spherical co-assemblies with an average diameter about 210?nm were excellent magnetic responsive and quite stable even up to 2 months in deionized water. The pH-liable capability of these co-assemblies was revealed by disassembly of the formed superstructures with destruction of the built inclusion complexes. The disassembly process was monitored by SEM, TEM, DLS and fluorescent molecules probe. After disassembly of the co-assemblies caused by protonation of nitrogens in APD, hydrophobic PGMA-APD lacking of interactions with the Fe3O4@AJNPs chains was precipitated, and the remained Fe3O4@AJNPs turned to re-assemble to self-assemblies. Besides, the recyclable Fe3O4@APJNs could reassembly with additional PGMA-APD to build co-assemblies with a uniform morphology for several times. These pH-sensitive co-assemblies with high stability, good magnetic responsiveness and cytocompatibility could be used as pH-responsive vehicles within which to encapsulate drugs for subsequent controlled release.

SUBMITTER: Cai S

PROVIDER: S-EPMC6184715 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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pH-responsive superstructures prepared via the assembly of Fe3O4 amphipathic Janus nanoparticles.

Cai Shuang S Luo Bin B Zhan Xiaohui X Zhou Xiaoxi X Lan Fang F Yi Qiangying Q Wu Yao Y

Regenerative biomaterials 20180712 5

The strategy of using Fe3O4 amphiphilic Janus nanoparticles (Fe3O4@AJNPs) bearing β-cyclodextrin (β-CD) and aminopyridine (APD) functionalized polymethyl methacrylate (PGMA) to construct pH-stimuli responsive co-assemblies through host-guest interactions between β-CD and APD was proposed. The spherical co-assemblies with an average diameter about 210 nm were excellent magnetic responsive and quite stable even up to 2 months in deionized water. The pH-l ...[more]

PMID: 30338123

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Project description:Protein-based vaccines offer a number of important advantages over organism-based vaccines but generally elicit poor CD8(+) T cell responses. We have previously demonstrated that pH-responsive, endosomolytic polymers can enhance protein antigen delivery to major histocompatibility complex class I (MHC-I) antigen presentation pathways thereby augmenting CD8(+) T cell responses following immunization. Here, we describe a new family of nanocarriers for protein antigen delivery assembled using architecturally distinct pH-responsive polymers. Reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize linear, hyperbranched, and core-crosslinked copolymers of 2-(N,N-diethylamino)ethyl methacrylate (DEAEMA) and butyl methacrylate (BMA) that were subsequently chain extended with a hydrophilic N,N-dimethylacrylamide (DMA) segment copolymerized with thiol-reactive pyridyl disulfide (PDS) groups. In aqueous solution, polymer chains assembled into 25 nm micellar nanoparticles and enabled efficient and reducible conjugation of a thiolated protein antigen, ovalbumin. Polymers demonstrated pH-dependent membrane-destabilizing activity in an erythrocyte lysis assay, with the hyperbranched and cross-linked polymer architectures exhibiting significantly higher hemolysis at pH ≤ 7.0 than the linear diblock. Antigen delivery with the hyperbranched and cross-linked polymer architecture enhanced in vitro MHC-I antigen presentation relative to free antigen, whereas the linear construct did not have a discernible effect. The hyperbranched system elicited a four- to fivefold increase in MHC-I presentation relative to the cross-linked architecture, demonstrating the superior capacity of the hyperbranched architecture in enhancing MHC-I presentation. This work demonstrates that the architecture of pH-responsive, endosomolytic polymers can have dramatic effects on intracellular antigen delivery, and offers a promising strategy for enhancing CD8(+) T cell responses to protein-based vaccines.

Dataset Information

PH-responsive superstructures prepared via the assembly of Fe3O4 amphipathic Janus nanoparticles.

Publications

pH-responsive superstructures prepared via the assembly of Fe<sub>3</sub>O<sub>4</sub> amphipathic Janus nanoparticles.

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