Covalent incorporation of tobacco mosaic virus increases the stiffness of poly(ethylene glycol) diacrylate hydrogels

• Published in: RSC advances Vol. 8; no. 9; pp. 4686 - 4694
• Main Authors: Southan, A, Lang, T, Schweikert, M, Tovar, G E M, Wege, C, Eiben, S
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 01-01-2018; The Royal Society of Chemistry
• Subjects: Biosensors; Chemistry; Coupling; Covalence; Crosslinking; Electron microscopy; Hydrogels; Michael reaction; Polyethylene glycol; Proteins; Stiffness; Storage modulus; Tissue engineering; Tobacco; Viruses
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c7ra10364f

Hydrogels are versatile materials, finding applications as adsorbers, supports for biosensors and biocatalysts or as scaffolds for tissue engineering. A frequently used building block for chemically cross-linked hydrogels is poly(ethylene glycol) diacrylate (PEG-DA). However, after curing, PEG-DA hydrogels cannot be functionalized easily. In this contribution, the stiff, rod-like tobacco mosaic virus (TMV) is investigated as a functional additive to PEG-DA hydrogels. TMV consists of more than 2000 identical coat proteins and can therefore present more than 2000 functional sites per TMV available for coupling, and thus has been used as a template or building block for nano-scaled hybrid materials for many years. Here, PEG-DA (
= 700 g mol
) hydrogels are combined with a thiol-group presenting TMV mutant (TMV
). By covalent coupling of TMV
into the hydrogel matrix
the thiol-Michael reaction, the storage modulus of the hydrogels is increased compared to pure PEG-DA hydrogels and to hydrogels containing wildtype TMV (wt-TMV) which is not coupled covalently into the hydrogel matrix. In contrast, the swelling behaviour of the hydrogels is not altered by TMV
or wt-TMV. Transmission electron microscopy reveals that the TMV particles are well dispersed in the hydrogels without any large aggregates. These findings give rise to the conclusion that well-defined hydrogels were obtained which offer the possibility to use the incorporated TMV as multivalent carrier templates
for enzymes in future studies.