Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Pharmaceutical Science, Southwest University, Chongqing 400715, China.
Nanoscale. 2017 Nov 16;9(44):17334-17341. doi: 10.1039/c7nr05539k.
Functional engineering is a crucial prerequisite for specific and wide applications of optical probes. In this study, we proposed a facile active structure preservation (ASP) method to directly develop new self-functional graphitic carbon dots (g-CDs) through a hydrothermal synthesis route by taking ciprofloxacin hydrochloride, an antibiotic belonging to a group of fluoroquinolone drugs, as an example. To retain the functional structures of the starting materials, the reaction temperature is intentionally controlled below the decomposition temperature of the reactants that hold the functional groups. As a proof of concept, we successfully prepared g-CDs with ciprofloxacin-like structures on its surface, as identified by mass spectrometric (MS) analysis. The as-prepared g-CDs not only exhibit effective antibacterial activity towards the bacteria Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative), but can also optically sense pH in the range from 5.02 to 9.91. Furthermore, the g-CDs can coordinate with aluminum ions to show a chelation-enhanced photoluminescence (CHEP) effect. These results indicate that the ASP method can be promising for engineering CDs with various properties.
功能工程是光学探针特定和广泛应用的关键前提。在本研究中，我们提出了一种简便的主动结构保留（ASP）方法，通过水热合成路线，以盐酸环丙沙星（一种属于氟喹诺酮类药物的抗生素）为例，直接开发新的自功能石墨碳点（g-CDs）。为了保留起始材料的功能结构，反应温度故意控制在保持功能基团的反应物分解温度以下。作为概念验证，我们通过质谱（MS）分析成功地制备了表面具有类似环丙沙星结构的 g-CDs。所制备的 g-CDs 不仅对革兰氏阳性的金黄色葡萄球菌（Staphylococcus aureus）和革兰氏阴性的大肠杆菌（Escherichia coli）具有有效的抗菌活性，而且还可以在 5.02 至 9.91 的 pH 值范围内进行光学感应。此外，g-CDs 可以与铝离子配位，显示出螯合增强的光致发光（CHEP）效应。这些结果表明，ASP 方法有望用于工程化具有各种性质的 CDs。
