Heteroatom-engineered multicolor lignin carbon dots enabling bimodal fluorescent off-on detection of metal-ions and glutathione

作者：Zhou, Pengfei; Xu, Jikun^*; Hou, Xinyan; Dai, Lin; Zhang, Jiaming; Xiao, Xiao^*; Huo, Kaifu

来源：International Journal of Biological Macromolecules, 2023, 253: 126714.

DOI：10.1016/j.ijbiomac.2023.126714

• Multicolor lignin carbon dots
• Heteroatom-doping
• Bimodal off-on sensing

Carbon dots (CDs) have emerged as a promising subclass of optical nanomaterials with versatile functions in multimodal biosensing. Howbeit the rapid, reliable and reproducible fabrication of multicolor CDs from renewable lignin with unique groups (e.g., -OCH3, -OH and -COOH) and alterable moieties (e.g., beta-O-4, phe-nylpropanoid structure) remains challenging due to difficult-to-control molecular behavior. Herein we proposed a scalable acid-reagent strategy to engineer a family of heteroatom-doped multicolor lignin carbon dots (LCDs) that are functioned as the bimodal fluorescent off-on sensing of metal-ions and glutathione (GSH). Benefiting from the modifiable photophysical structure via heteroatom-doping (N, S, W, P and B), the multicolor LCDs (blue, green and yellow) with a controllable size distribution of 2.06-2.22 nm deliver the sensing competences to fluorometric probing the distinctive metal-ion systems (Fe3+, Al3+ and Cu2+) under a broad response interval (0-500 mu M) with excellent sensitivity and limit of detection (LOD, 0.45-3.90 mu M). Meanwhile, we found that the addition of GSH can efficiently restore the fluorescence of LCDs by forming a stable Fe3+-GSH complex with a LOD of 0.97 mu M. This work not only sheds light on evolving lignin macromolecular interactions with tunable luminescent properties, but also provides a facile approach to synthesize multicolor CDs with advanced functionalities.

• 单位
  jk; Sichuan University; Huazhong University of Science and Technology