Structure and stability of complex coacervate core micelles with lysozyme

Saskia Lindhoud*, Renko de Vries, Willem Norde, Martien A. Cohen Stuart

*Corresponding author for this work

    Research output: Contribution to journalArticleAcademicpeer-review

    55 Citations (Scopus)

    Abstract

    Encapsulation of enzymes by polymers is a promising method to influence their activity and stability. Here, we explore the use of complex coacervate core micelles for encapsulation of enzymes. The core of the micelles consists of negatively charged blocks of the diblock copolymer PAA(42)PAAm(417) and the positively charged homopolymer PDMAEMA(150). For encapsulation, part of the positively charged homopolymer was replaced by the positively charged globular protein lysozyme. We have studied the formation, structure, and stability of the resulting micelles for three different mixing ratios of homopolymer and lysozyme: a system predominantly consisting of homopolymer, a system predominantly consisting of lysozyme, and a system where the molar ratio between the two positively charged molecules was almost one. We also studied complexes made of only lysozyme and PAA(42)PAAm(417). Complex formation and the salt-induced disintegration of the complexes were studied using dynamic light-scattering titrations. Small-angle neutron scattering was used to investigate the structures of the cores. We found that micelles predominantly consisting of homopolymer are spherical but that complex coacervate core micelles predominantly consisting of lysozyme are nonspherical. The stability of the micelles containing a larger fraction of lysozyme is lower.

    Original languageEnglish
    Pages (from-to)2219-2227
    Number of pages9
    JournalBiomacromolecules
    Volume8
    Issue number7
    DOIs
    Publication statusPublished - Jul-2007

    Keywords

    • CHARGED BLOCK-COPOLYMERS
    • ENTRAPPING ENZYME MOLECULES
    • SUCCINYLATED LYSOZYME
    • POLYMERS
    • NANOPARTICLES
    • SCATTERING
    • GLUTARALDEHYDE
    • SURFACTANTS
    • PROTEINS
    • DESIGN

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