Department of Chemistry, Chemical Biology and Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey 07030, United States.
Biomacromolecules. 2010 Dec 13;11(12):3448-56. doi: 10.1021/bm100975w. Epub 2010 Oct 28.
We report on the layer-by-layer design principles of poly(methacrylic acid) (PMAA) ultrathin hydrogel coatings that release antimicrobial agents (AmAs) in response to pH variations. The studied AmAs include gentamicin and an antibacterial cationic peptide L5. Adipic acid dihydrazide (AADH) is a cross-linker which, relative to ethylenediamine (EDA), increases the hydrogel hydrophobicity and introduces centers for hydrogen bonding to AmAs. AmA retention in AADH-cross-linked hydrogels in high-salt solutions was enhanced while AmA release at low pH was suppressed. L5 retains its antibacterial activity toward planktonic Staphylococcus epidermidis after release from PMAA hydrogels in response to pH decreases in the surrounding medium due to bacterial growth. Staphylococcus epidermidis adhesion and colonization was almost completely inhibited by L5 loading of hydrogels. The AmA-releasing and AmA-retaining properties of these hydrogel coatings provide new opportunities to study the fundamental mechanisms of AmA-coating-bacteria interactions and develop a new class of clinically relevant antibacterial coatings for medical devices.
我们报告了聚（甲基丙烯酸）（PMAA）超薄水凝胶涂层的逐层设计原则，这些涂层可以响应 pH 值变化释放抗菌剂（AmAs）。研究的 AmAs 包括庆大霉素和一种抗菌阳离子肽 L5。己二酰肼（AADH）是一种交联剂，与乙二胺（EDA）相比，它增加了水凝胶的疏水性，并引入了与 AmAs 形成氢键的中心。在高盐溶液中，AADH 交联水凝胶中 AmA 的保留率增加，而在低 pH 值下，AmA 的释放受到抑制。由于细菌生长导致周围介质 pH 值降低，L5 从 PMAA 水凝胶中释放后，对浮游表皮葡萄球菌仍保持抗菌活性。L5 负载水凝胶几乎完全抑制了表皮葡萄球菌的黏附和定植。这些水凝胶涂层的 AmA 释放和 AmA 保留性能为研究 AmA-涂层-细菌相互作用的基本机制以及开发一类新的临床相关抗菌医疗器械涂层提供了新的机会。
