Adequately decorated gold nanoparticles (GNPs) have excellent antibiotic activities against multidrug‐resistant (MDR) bacteria. Nanoparticles exhibiting Gram selective antibacterial actions are beneficial to precise therapy. Here, we present a strategy to tune the antibacterial spectrum of a small molecule (4,6‐diamino‐2‐pyrimidinethiol, DAPT)‐modified GNPs (DAPT‐GNPs, DGNPs) by adjusting their sizes. Compared to large (ca. 14 nm diameter) DGNPs (lDGNPs) and medium‐sized (3–4 nm diameter) DGNPs (mDGNPs), which have no antibacterial effect or only target Gram‐negative (G−) bacteria, ultrasmall DGNPs (uDGNPs, <2 nm) have a broad antibacterial spectrum, especially showing an over 60‐fold increase in antibacterial efficacy against Gram‐positive (G+) bacteria. Moreover, the uDGNPs‐functionalized scaffolds (agarose gel) can serve as general wound dressings for healing burnt infections. Our strategy is insightful for exploring properties of the nanomaterials and their applications.

中文翻译：

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通过减小尺寸来激活4,6-二氨基-2-嘧啶硫醇修饰的金纳米颗粒的抗菌作用。

装饰充分的金纳米颗粒（GNP）对多药耐药（MDR）细菌具有出色的抗生素活性。表现出革兰氏选择性抗菌作用的纳米颗粒有利于精确治疗。在这里，我们提出了一种通过调整小分子（4,6-二氨基-2-嘧啶硫醇，DAPT）修饰的GNP（DAPT-GNP，DGNP）的抗菌谱的策略。与不具有抗菌作用或仅具有革兰氏阴性（G-）细菌作用的中型DGNP（lDGNP）和中型（直径3-4 nm）DGNP（mDGNP）相比，超小型DGNPs（ uDGNPs（<2 nm）具有广泛的抗菌谱，特别是对革兰氏阳性（G +）细菌的抗菌效力提高了60倍以上。此外，uDGNPs功能化的支架（琼脂糖凝胶）可作为治愈烧伤感染的一般伤口敷料。我们的策略对于探索纳米材料的特性及其应用具有洞察力。