The global state of antibiotic resistance highlights the necessity for new drugs that can treat a wide range of microbial infections. Drug repurposing has several advantages, including lower costs and improved safety compared to developing a new compound. The aim of the current study is to evaluate the repurposed antimicrobial activity of Brimonidine tartrate (BT), a well-known antiglaucoma drug, and to potentiate its antimicrobial effect by using electrospun nanofibrous scaffolds. BT-loaded nanofibers were fabricated in different drug concentrations (1.5, 3, 6, and 9%) via the electrospinning technique using two biopolymers (PCL and PVP). Then, the prepared nanofibers were characterized by SEM, XRD, FTIR, swelling ratio, and in vitro drug release. Afterward, the antimicrobial activities of the prepared nanofibers were investigated in vitro using different methods against several human pathogens and compared to the free BT. The results showed that all nanofibers were prepared successfully with a smooth surface. The diameters of nanofibers were reduced after loading of BT compared to the unloaded ones. In addition, scaffolds showed controlled-drug release profiles that were maintained for more than 7 days. The in vitro antimicrobial assessments revealed good activities for all scaffolds against most of the investigated human pathogens, particularly the one prepared with 9% BT which showed superiority in the antimicrobial effect over other scaffolds. To conclude, our findings proved the capability of nanofibers in loading BT and improving its repurposed antimicrobial efficacy. Therefore, it could be a promising carrier for BT to be used in combating numerous human pathogens.

中文翻译：

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用于多功能生物医学应用的新型长效酒石酸溴莫尼定负载 PCL/PVP 纳米纤维：制造、表征和抗菌评估

全球抗生素耐药性状况凸显了开发能够治疗多种微生物感染的新药的必要性。与开发新化合物相比，药物再利用有几个优势，包括成本更低和安全性更高。当前研究的目的是评估溴莫尼定酒石酸盐 (BT)（一种著名的抗青光眼药物）的再利用抗菌活性，并通过使用电纺纳米纤维支架增强其抗菌作用。通过使用两种生物聚合物（PCL 和 PVP）的静电纺丝技术，以不同的药物浓度（1.5、3、6 和 9%）制备了载有 BT 的纳米纤维。然后，通过SEM、XRD、FTIR、溶胀比和体外表征制备的纳米纤维。药物释放。之后，使用不同的方法在体外研究了制备的纳米纤维对几种人类病原体的抗菌活性，并与游离 BT 进行了比较。结果表明，所有纳米纤维均成功制备，表面光滑。与未加载的纳米纤维相比，加载 BT 后纳米纤维的直径减小。此外，支架显示出可维持 7 天以上的受控药物释放曲线。体外_抗菌评估显示所有支架对大多数研究的人类病原体都有良好的活性，特别是用 9% BT 制备的支架，其抗菌效果优于其他支架。总而言之，我们的研究结果证明了纳米纤维在加载 BT 和提高其重新利用的抗菌功效方面的能力。因此，它可能是一种很有前途的 BT 载体，可用于对抗多种人类病原体。