Herron Maggie, Schurr Michael J, Murphy Christopher J, McAnulty Jonathan F, Czuprynski Charles J, Abbott Nicholas L
Department of Chemical and Biological Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, WI, 53706, USA.
Department of Surgery, School of Medicine, University of Colorado-Denver, 12631 E. 17th Avenue, Aurora, CO, 80045, USA.
Adv Healthc Mater. 2015 Dec 30;4(18):2849-59. doi: 10.1002/adhm.201500599. Epub 2015 Nov 24.
The persistence of bacterial biofilms in chronic wounds delays wound healing. Although Ga(3+) can inhibit or kill biofilms, precipitation as Ga(OH)3 has prevented its use as a topical wound treatment. The design of a microfilm construct comprising a polyelectrolyte film that releases noncytotoxic concentrations of Ga(3+) over 20 d and a dissolvable micrometer-thick film of polyvinylalcohol that enables facile transfer onto biomedically important surfaces is reported. By using infrared spectroscopy, it is shown that the density of free carboxylate/carboxylic acid and amine groups within the polyelectrolyte film regulates the capacity of the construct to be loaded with Ga(3+) and that the density of covalent cross-links introduced into the polyelectrolyte film (amide-bonds) controls the release rate of Ga(3+) . Following transfer onto the wound-contact surface of a biologic wound dressing, an optimized construct is demonstrated to release ≈0.7 μg cm(-2) d(-1) of Ga(3+) over 3 weeks, thus continuously replacing Ga(3+) lost to precipitation. The optimized construct inhibits formation of P. aeruginosa (two strains; ATCC 27853 and PA01) biofilms for up to 4 d and causes pre-existing biofilms to disperse. Overall, this study provides designs of polymeric constructs that permit facile modification of the wound-contacting surfaces of dressings and biomaterials to manage biofilms.
细菌生物膜在慢性伤口中的持续存在会延迟伤口愈合。尽管Ga(3+)可以抑制或杀死生物膜，但由于会沉淀为Ga(OH)3，它一直无法用作局部伤口治疗。本文报道了一种微膜构建体的设计，该构建体包括一种聚电解质膜，可在20天内释放无细胞毒性浓度的Ga(3+)，以及一种可溶解的微米厚聚乙烯醇膜，能够轻松转移到具有重要生物医学意义的表面。通过红外光谱表明，聚电解质膜中游离羧酸盐/羧酸和胺基团的密度调节了构建体负载Ga(3+)的能力，并且引入聚电解质膜中的共价交联（酰胺键）密度控制了Ga(3+)的释放速率。在转移到生物伤口敷料的伤口接触表面后，一种优化的构建体在3周内释放约0.7μg cm(-2) d(-1)的Ga(3+)，从而不断补充因沉淀而损失的Ga(3+)。优化后的构建体可抑制铜绿假单胞菌（两种菌株；ATCC 27853和PA01）生物膜的形成长达4天，并使预先存在的生物膜分散。总体而言，本研究提供了聚合物构建体的设计，可轻松修饰敷料和生物材料的伤口接触表面以控制生物膜。
