Dev Keshav, Singh Shiva, Bhardwaj Shakshi, Samanta Somnath, Saroha Ritika, Roy Partha, Ghosh Kaushik, Maji Pradip K
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur campus, Saharanpur 247001, Uttar Pradesh, India.
Langmuir. 2025 Jul 8;41(26):16843-16856. doi: 10.1021/acs.langmuir.5c00961. Epub 2025 Jun 20.
Biomass-derived carbon dots (CDs) offer a sustainable alternative for nanomaterial synthesis; however, their photoluminescence properties often remain suboptimal. This study targets a green and cost-effective hydrothermal approach to prepare nitrogen-doped carbon dots (NCDs) using agricultural residues as precursors, with amine-rich waste serving as the nitrogen source. The resulting NCDs exhibited low cytotoxicity, exceptional water solubility, high stability, and excellent biocompatibility. The resulting NCDs exhibited a substantial improvement in fluorescence emission, in contrast to the nondoped CDs. Additionally, the NCDs demonstrated stability across a pH range of 2-12 and exhibited excellent selectivity and sensitivity for cobalt(II) ion detection, supported by computational studies, with efficient fluorescence quenching, achieving a detection limit of 39.8 nM. Importantly, the quenched fluorescence could be efficiently restored by adding EDTA. Additionally evaluated for their potential in nitric oxide (NO) sensing, these NCDs had a limit of detection of 53.2 μM. As NO is a fundamental signaling molecule in many physiological processes, its detection is rather crucial. Nitrogen doping effectively tuned the electronic structure of the NCDs, leading to evolved optical properties and an improved sensing ability. These NCDs were also assessed for their potential in bioimaging applications due to low cytotoxicity and efficient cellular uptake.
生物质衍生的碳点（CDs）为纳米材料合成提供了一种可持续的替代方案；然而，它们的光致发光性能往往仍不理想。本研究旨在采用一种绿色且经济高效的水热法，以农业废弃物为前驱体、富含胺的废料为氮源来制备氮掺杂碳点（NCDs）。所得的NCDs表现出低细胞毒性、出色的水溶性、高稳定性和优异的生物相容性。与未掺杂的CDs相比，所得的NCDs在荧光发射方面有显著改善。此外，NCDs在pH值为2至12的范围内表现出稳定性，并且在计算研究的支持下，对钴（II）离子检测表现出优异的选择性和灵敏度，具有高效的荧光猝灭，检测限达到39.8 nM。重要的是，通过添加乙二胺四乙酸（EDTA）可以有效地恢复猝灭的荧光。此外，对这些NCDs在一氧化氮（NO）传感方面的潜力进行了评估，其检测限为53.2 μM。由于NO是许多生理过程中的基本信号分子，其检测相当关键。氮掺杂有效地调节了NCDs的电子结构，导致其光学性质的演变和传感能力的提高。由于低细胞毒性和高效的细胞摄取，这些NCDs还被评估了在生物成像应用中的潜力。
