Jump to main content
Jump to site search


Diblock brush-arm star copolymers via a core-first/graft-from approach using γ-cyclodextrin and ROMP: a modular platform for drug delivery

Author affiliations

Abstract

The design and synthesis of a novel multifunctional core initiator based on γ-cyclodextrin (γ-CD) functionalized with eight norbornenes is reported, and a core-first approach to make eight-arm star polymers using ring-opening metathesis polymerization is carried out by grafting-from the initiator using norbornene-functionalized hexaethylene glycol. The living nature of the polymerization was verified through chain extension of the ω-functional arms with norbornene-functionalized poly(ethylene glycol) (PEG, Mn ≈ 2 kDa) to generate water-soluble diblock brush-arm star copolymers (DBASCs) with high molar masses (Mn,NMR = 187–268 kDa) and low dispersities (Đ = 1.12–1.19). The size of the corresponding star polymers was confirmed by transmission electron microscopy and dynamic light scattering (Dh ≈ 10.0–11.0 nm). The thermal properties (e.g., Tg) of the DBASCs were determined by thermogravimetric analysis and differential scanning calorimetry, the latter of which showed well-ordered materials in the solid state (prominent Tc and Tm peaks). The long-range order and crystallinity of solid-state DBASCs was further supported by well-defined powder X-ray diffraction patterns. Lastly, since γ-CD possesses an order of magnitude greater solubility in water and enhanced drug-binding capabilities compared to that for β-CD, a representative DBASC was evaluated against healthy human umbilical vein endothelial cells (and exhibited low toxicity), and was also investigated as a delivery vehicle for the anticancer drug doxorubicin as its hydrochloride salt (DOX·HCl), resulting in greater potency against MCF-7 breast cancer cells relative to that of the free DOX·HCl treatment. The star polymers reported herein represent a new modular polymeric platform with potential applications in nanostructure self-assembly and drug delivery.

Graphical abstract: Diblock brush-arm star copolymers via a core-first/graft-from approach using γ-cyclodextrin and ROMP: a modular platform for drug delivery

Back to tab navigation

Supplementary files

Publication details

The article was received on 01 Aug 2019, accepted on 14 Oct 2019 and first published on 15 Oct 2019


Article type: Paper
DOI: 10.1039/C9PY01146C
Polym. Chem., 2019, Advance Article

  •   Request permissions

    Diblock brush-arm star copolymers via a core-first/graft-from approach using γ-cyclodextrin and ROMP: a modular platform for drug delivery

    R. Li, X. Li, Y. Zhang, A. O. Delawder, N. D. Colley, E. A. Whiting and J. C. Barnes, Polym. Chem., 2019, Advance Article , DOI: 10.1039/C9PY01146C

Search articles by author

Spotlight

Advertisements