Modification of poly(styrene-b-isobutylene-b-styrene) using hyaluronic acid via surface graft polymerization and cytotoxicity investigation

Poly(styrene- b -isobutylene- b -styrene) (SIBS) is a biomedical elastomer with excellent overall properties. However, the low surface energy and the surface hydrophobicity of SIBS have limited its application as a human implantable material. To improve its biocompatibility, in this work, hyaluronic acid (HA) was introduced onto the surface of SIBS. Firstly, glycidyl methacrylate (GMA) and HA were employed to prepare GMA-modified HA (GMHA) via grafting reaction. Due to the introduction of carbon–carbon double bonds on the side chain of HA, the GMHA could be used for free radical polymerization between SIBS. The effects of UV illumination time, GMHA concentration, and initiator concentration on the grafting ratio were investigated. FTIR, 1H NMR, and XPS confirmed the successful grafting of HA onto SIBS. The experimental results showed that the surface modification method not only ensured that the excellent properties of the SIBS would not be destroyed but also improved its surface properties successfully. Besides, the MTT assay indicated that the GMHA-modified SIBS was not bio-toxic, so it could meet the need to expand its use in the biomedical fields.