In the current study, we utilize leaves of Aerva lanata as the precursor to produce carbon dots (CDs) adopting a one-step hydrothermal approach without the use of extra chemical reagents or surface modification. They have hydroxyl and carboxyl groups as surface functionalities, were well soluble in water, were biocompatible, and exhibited bright fluorescence. The applications of the prepared CDs in three broad areas were carefully described. As a fluorescence-based sensor, the prepared sensor was able to sense ciprofloxacin. Ciprofloxacin enhanced the fluorescent intensity of CDs, and a linear correlation between the intensity of fluorescence and the concentration of ciprofloxacin in a wide range with an LOD of 0.4 nM was observed. The mechanism behind the fluorescence enhancement seen with the addition of ciprofloxacin was revealed to be charge transfer and hydrogen bonding. As an electrochemical probe, a carbon dot-modified glassy carbon electrode was able to sense copper ions with good selectivity and an LOD of 4 nM. Cu(II) electrochemical sensing was comprehensively examined, with a complete description of the electron transport process. The anticounterfeiting properties of the synthesized CDs were also proven. The successful real sample analysis also paved the way for an environment-friendly sensor for exhibiting its potential for multifaceted applications. This study not only introduced a new carbon dot to improve our understanding of material properties but also delved into all of its possible applications.

Graphical abstract

中文翻译：

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作为荧光和电化学传感器和荧光墨水的仿生新型碳点

在目前的研究中，我们利用了Aerva lanata的叶子作为生产碳点 (CD) 的前体，采用一步水热法，无需使用额外的化学试剂或表面改性。它们具有羟基和羧基作为表面官能团，易溶于水，具有生物相容性，并表现出明亮的荧光。详细描述了制备的 CD 在三个广泛领域的应用。作为基于荧光的传感器，制备的传感器能​​够感应环丙沙星。环丙沙星增强了CDs的荧光强度，并观察到荧光强度与环丙沙星浓度在很宽的范围内呈线性相关，LOD为0.4 nM。发现添加环丙沙星后荧光增强的机制是电荷转移和氢键合。作为电化学探针，碳点修饰的玻碳电极能够以良好的选择性和 4 nM 的 LOD 检测铜离子。全面检查了 Cu(II) 电化学传感，并完整描述了电子传输过程。还证明了合成 CD 的防伪特性。成功的实际样品分析也为环境友好型传感器铺平了道路，以展示其在多方面应用的潜力。这项研究不仅引入了一种新的碳点来提高我们对材料特性的理解，而且还深入研究了它的所有可能应用。完整描述电子传输过程。还证明了合成 CD 的防伪特性。成功的实际样品分析也为环境友好型传感器铺平了道路，以展示其在多方面应用的潜力。这项研究不仅引入了一种新的碳点来提高我们对材料特性的理解，而且还深入研究了它的所有可能应用。完整描述电子传输过程。还证明了合成 CD 的防伪特性。成功的实际样品分析也为环境友好型传感器铺平了道路，以展示其在多方面应用的潜力。这项研究不仅引入了一种新的碳点来提高我们对材料特性的理解，而且还深入研究了它的所有可能应用。

图形概要