Coroaba Adina, Ignat Maurusa, Carp Oana-Elena, Stan Corneliu S, Filipiuc Silviu I, Uritu Cristina M, Simionescu Natalia, Marangoci Narcisa-Laura, Pinteala Mariana, Ania Conchi O
Centre of Advanced Research in Bionanoconjugates and Biopolymers, "Petru Poni" Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, Iasi, 700487, Romania.
Faculty of Chemical Engineering and Environmental Protection, "Gheorghe Asachi" Technical University of Iasi, 73 Dimitrie Mangeron Ave., Iasi, 700050, Romania.
Sci Rep. 2025 Jul 16;15(1):25834. doi: 10.1038/s41598-025-11676-6.
Nanomaterials with dual-functions integrating diagnostic and therapeutic abilities have attracted the interest in biomedical applications, and low-dimensional carbon dots have shown their potentialities in the field owing to their versatile optical and physicochemical properties. Yet the link between the surface emissive states and their structure and composition is not well understood, and their stability and biocompatibility needs to be further investigated. We have prepared a series of N- and O-doped carbon dots from a commercial commodity with a high surface functionalization, and performed a deep analysis to rationalize the structure-performance indicators that control their fluorescence, cytotoxicity and antioxidant properties. The synthesized carbon dots exhibited broad multiple surface emissive states: a bright blue emission at 430 nm governed by electronic transitions involving pyridones and carbonyl moieties, and a greenish emission at 500 nm due to transitions involving C-N and C-O groups or trap states. The carbon dots displayed good photostability with negligible photobleaching over continuous excitation during 2 h. The carbon dots also displayed good antioxidant activity correlated to the electron storage capacity of the aromatic core and O- and N- groups with proton exchange capacity. The carbon dots showed excellent cytotoxicity on human gingival fibroblast cell lines, and good response in in vitro fluorescence imaging over a wide concentrations range (0.05-1 mg/mL), similar to other contrast agents, demonstrating the potential of these N-O- doped carbon dots in imaging applications.
具有诊断和治疗双重功能的纳米材料在生物医学应用中引起了人们的兴趣，低维碳点由于其多样的光学和物理化学性质而在该领域展现出潜力。然而，表面发射态与其结构和组成之间的联系尚未得到很好的理解，其稳定性和生物相容性仍需进一步研究。我们从一种具有高表面功能化的商业商品制备了一系列氮和氧掺杂的碳点，并进行了深入分析，以合理化控制其荧光、细胞毒性和抗氧化性能的结构 - 性能指标。合成的碳点表现出多种表面发射态：在430 nm处有明亮的蓝色发射，由涉及吡啶酮和羰基部分的电子跃迁控制；在500 nm处有绿色发射，归因于涉及C - N和C - O基团或陷阱态的跃迁。碳点在连续激发2小时期间表现出良好的光稳定性，光漂白可忽略不计。碳点还表现出良好的抗氧化活性，这与芳香核以及具有质子交换能力的氧和氮基团的电子存储能力相关。碳点对人牙龈成纤维细胞系显示出优异的细胞毒性，并且在宽浓度范围（0.05 - 1 mg/mL）内的体外荧光成像中表现良好，类似于其他造影剂，证明了这些氮 - 氧掺杂碳点在成像应用中的潜力。
