Temperature- and pH-sensitive interpenetrating polymer networks grafted on PP: Cross-linking irradiation dose as a critical variable for the performance as vancomycin-eluting systems
- 作者：Franklin Muñ ; oz-Muñ ; oza ; Juan-Carlos Ruizb ; Carmen Alvarez-Lorenzoc ; Angel Concheiroc ; Emilio Bucioa ; ebucio@nucleares.unam.mx
- 关键词：IPN ; Gamma irradiation grafting ; Stimuli-responsive drug release ; Drug/device combination product ; Surface functionalization
- 刊名：Radiation Physics and Chemistry
- 出版年：2012
- 期刊代码：68_0969806x
- 类别：ph
- 出版时间：May, 2012
- 卷：81
- 期：5
- 页码：531-540
- 文件大小：1199 K
摘要
This work focuses on the effect of gamma-ray radiation conditions on the stimuli-responsiveness and drug-eluting performance of polypropylene (PP) substrates grafted with interpenetrating networks of N-isopropylacrylamide (NIPAAm) and acrylic acid (AAc). PNIPAAm was cross-linked applying 10-100 kGy doses in the presence and absence of the chemical cross-linker N,N鈥?methylenebisacrylamide (MBAAm). Then, the net-PP-g-PNIPAAm was interpenetrated with PAAc synthesized under a 2.5 kGy dose to obtain net-PP-g-PNIPAAm-inter-net-PAAc films. The amount of grafted PNIPAAm (80%, 125%and 145%levels) and the cross-linking radiation dose (10, 40 and 70 kGy levels) strongly determine the interpenetration of PAAc, the swelling degree, the amount of vancomycin loaded and its release rate. The chemical cross-linker only caused a minor decrease in the degree of swelling. The higher the PNIPAAm grafted on PP and the lower the cross-linking radiation dose, the more the PAAc in the IPN and, consequently, the higher the vancomycin loaded through specific interactions and the more sustained the release (>8 h). The films possessing these features exhibited vancomycin release rate per surface unit suitable to prevent bacterial growth. Thus, adequate tuning of the radiation doses during grafting and cross-linking of the PNIPAAm networks may enable to achieve surface-modified materials for medical devices with an antibiofilm performance.