Using high-energy phosphate as energy-donor and nucleus growth-inhibitor to prepare carbon dots for hydrogen peroxide related biosensing

• Published in: Sensors and actuators. B, Chemical Chemical, 2018-06, Vol.262, p.780-788
• Main Authors: Li, Na, Liu, Shi Gang, Dong, Jiang Xue, Fan, Yu Zhu, Ju, Yan Jun, Luo, Hong Qun, Li, Nian Bing
• Format: Article
• Language: English
• Subjects: Biosensors; Carbon dots; Chemical synthesis; Fluorescence; Fluorescent indicators; Fluorescent sensor; Glucose oxidase; High-energy phosphate bond; Hydrogen peroxide; Inhibitors; Nuclei
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2018.02.051

[Display omitted] •C-dots fluorescence is enhanced by high-energy phosphate bond-mediated synthesis.•The important role of high-energy phosphate bond is discussed in detail.•The C-dots are applied for H2O2 and glucose detection with high sensitivity.•The fluorescent sensor shows applicability for glucose monitoring in clinical analysis. The various synthetic routes of carbon dots (C-dots) feature a considerable step toward their potential use in sensors and biotechnology. Herein, by coupling pyrophosphate introduction with high-energy phosphate bond design, the fluorescence performance of C-dots is improved greatly. The introduction of pyrophosphate acts as the nucleus growth-inhibitor to protect C-dots from assembling and growing into large carbon particles. The high-energy phosphate bond is designed as an energy-donor to provide energy for synthesizing C-dots. The C-dots exhibit enhanced fluorescence with a high quantum yield of 24.8%. Then the C-dots are employed as the fluorescent probe to develop hydrogen peroxide (H2O2)-related biosensors. The mechanism is based on the fluorescence quenching of C-dots caused by the highly reactive OH and Fe3+ during the Fenton reaction. A wide linear range (0.5–100 μM) and a low detection limit (0.195 μM) are achieved for H2O2 detection. Moreover, the probe can be applied to H2O2-related biosensing in the presence of oxidase. As a proof-of-concept, a glucose sensor is developed with glucose oxidase. The presented glucose sensor exhibits good selectivity and high sensitivity with a detection limit of 0.254 μM. Additionally, the practical application of the proposed biosensor has been confirmed by detecting glucose in human serum samples.