Carbon dots derived from expired drugs based ratiometric fluorescent sensor for horseradish peroxidase in fruits and vegetables and screening inhibitors

• Published in: Mikrochimica acta (1966) Vol. 191; no. 2; p. 109
• Main Authors: Wu, Wei, Shi, Yuhan, Liu, Jingya, Liu, Xiaoyu, Liu, Hao, Wang, Tao, Zhang, Guoqi, Xu, Zhihong
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.02.2024; Springer Nature B.V
• Subjects: Amoxicillin; Analytical Chemistry; Carbon; Carbon dots; Catalysis; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Enzyme activity; Fluorescent Dyes; Fluorescent indicators; Fruit; Fruits; Horseradish Peroxidase; Hydrogen peroxide; Inhibitors; Microengineering; Nanochemistry; Nanosensors; Nanotechnology; Original Paper; Peroxidase; Phenylenediamine; Raw materials; Screening; Solid wastes; Synthesis; Vegetables; Horseradish peroxidase; Carbon dots; Ratio fluorescence sensing; Amoxicillin
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-023-06160-9

Household storage of pharmaceuticals to extract raw materials synthesized from carbon points facilitates the utilization of solid waste resources. A novel ratiometric fluorescence sensing technique was developed to ascertain the presence of horseradish peroxidase (HRP) in fruits and vegetables. The method employed a fluorescent probe, synthesized from expired amoxicillin (referred to as carbon dots, or A-CDs), serving as a reference fluorophore. Additionally, 2,3-diaminophenazine (DAP) was utilized as a specific response signal. DAP resulted from a catalytic reaction system involving phenylenediamine and hydrogen peroxide under the catalysis of HRP. The fluorescence intensity corresponding to DAP at 562 nm exhibited a substantial increase, simultaneous with the fluorescence quenching of A-CDs at 450 nm. The ratiometric fluorescence nanosensors displayed a broad linear range and high sensitivity for the detection of HRP. Across the concentration range 0.01 to 6 U L −1 , the fluorescence intensity ratio between DAP and A-CDs demonstrated a proportional increase with rising HRP concentration, achieving an impressive detection limit of 0.002 U L −1 . The recovery of HRP in fruit and vegetable samples ranged from 96.1 to 103%, with an RSD value of less than 3.8%. The proposed method facilitated the screening of inhibitors of HRP enzyme activity, contributing to the preservation of freshness in fruits and vegetables. Graphical Abstract