Antibiotics delivery using dressings is an effective manner to treat chronic infected wounds, but it still faces the challenge of uncontrolled drug release. To address this issue, we developed pH-responsive electrospun nanofibers for controlled release of poorly water-soluble antibiotics. Specifically, the drug-loaded electrospun nanofibers were fabricated via coaxial electrospinning technique, with polycaprolactone (PCL) and drug acting as the core and pH-responsive acrylic copolymer Eudragit L100–55 serving as the sheath layer. Under alkaline conditions, all drugs release rapidly due to the dissolution of Eudragit L100–55, and first-order model well fits the release behavior. In contrast, the sheath layer swells under acidic conditions, causing poorly water-soluble drugs to be firmly trapped. Moreover, the drug-loaded nanofibers display completely different antibacterial activities due to distinct drug release behaviors under alkaline or acidic conditions. The current pH-responsive nanofibers shows superior controllability of poorly water-soluble drug release, revealing great prospects for treating chronic infected wounds.

使用敷料输送抗生素是治疗慢性感染伤口的有效方法，但仍面临药物释放失控的挑战。为了解决这个问题，我们开发了 pH 响应型电纺纳米纤维，用于控制难溶性抗生素的释放。具体来说，通过同轴静电纺丝技术制备了载药电纺纳米纤维，以聚己内酯（PCL）和药物为芯，pH响应性丙烯酸共聚物Eudragit L100-55作为鞘层。在碱性条件下，所有药物由于Eudragit L100-55的溶解而快速释放，并且一阶模型很好地拟合了释放行为。相反，鞘层在酸性条件下会膨胀，导致水溶性差的药物被牢固地捕获。此外，载药纳米纤维由于在碱性或酸性条件下不同的药物释放行为而表现出完全不同的抗菌活性。目前的pH响应性纳米纤维对难溶性药物释放表现出优异的可控性，为治疗慢性感染伤口展现了巨大的前景。