Dataset Information

Protein delivery nanosystem of six-arm copolymer poly(?-caprolactone)-poly(ethylene glycol) for long-term sustained release.

ABSTRACT:

Background

To address the issue of delivery of proteins, a six-arm copolymer, six-arm poly (?-caprolactone)-poly(ethylene glycol) (6S-PCL-PEG), was synthesized by a simple two-step reaction. Thereafter, the application of 6S-PCL-PEG as a protein carrier was evaluated.

Materials and methods

A six-arm copolymer, six-arm poly(?-caprolactone) (6S-PCL), was synthesized by ring-opening polymerization, with stannous octoate as a catalyst and inositol as an initiator. Then, poly(ethylene glycol) (PEG) was linked with 6S-PCL by oxalyl chloride to obtain 6S-PCL-PEG. Hydrogen-1 nuclear magnetic resonance spectrum, Fourier-transform infrared spectroscopy, and gel-permeation chromatography were conducted to identify the structure of 6S-PCL-PEG. The biocompatibility of the 6S-PCL-PEG was evaluated by a cell counting kit-8 assay. Polymeric nanoparticles (NPs) were prepared by a water-in-oil-in-water double emulsion (W₁/O/W₂) solvent evaporation method. The size distribution and zeta potential of NPs were determined by dynamic light scattering. Transmission electron microscopy was used to observe the morphology of NPs. Drug-loading capacity, encapsulation efficiency, and the release behavior of ovalbumin (OVA)-loading NPs were tested by the bicinchoninic acid assay kit. The stability and activity of OVA released from NPs were detected and the uptake of NPs was evaluated by NIH-3T3 cells.

Results

All results indicated the successful synthesis of amphiphilic copolymer 6S-PCL-PEG, which possessed excellent biocompatibility and could formulate NPs easily. High drug-loading capacity and encapsulation efficiency of protein NPs were observed. In vitro, OVA was released slowly and the bioactivity of OVA was maintained for over 28 days.

Conclusion

6S-PCL-PEG NPs prepared in this study show promising potential for use as a protein carrier.

SUBMITTER: Duan J

PROVIDER: S-EPMC5951147 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Protein delivery nanosystem of six-arm copolymer poly(ε-caprolactone)-poly(ethylene glycol) for long-term sustained release.

Duan Jianwei J Liu Chao C Liang Xiaoyu X Li Xuanling X Chen Youlu Y Chen Zuoguan Z Wang Xiaoli X Kong Deling D Li Yongjun Y Yang Jing J

International journal of nanomedicine 20180508

<h4>Background</h4>To address the issue of delivery of proteins, a six-arm copolymer, six-arm poly (ε-caprolactone)-poly(ethylene glycol) (6S-PCL-PEG), was synthesized by a simple two-step reaction. Thereafter, the application of 6S-PCL-PEG as a protein carrier was evaluated.<h4>Materials and methods</h4>A six-arm copolymer, six-arm poly(ε-caprolactone) (6S-PCL), was synthesized by ring-opening polymerization, with stannous octoate as a catalyst and inositol as an initiator. Then, poly(ethylene ...[more]

PMID: 29780245

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