Electrochemical sensor based on F,N-doped carbon dots decorated laccase for detection of catechol

Carbon dots (CDs) as a new type of carbon nanomaterial have gained tremendous attention due to their wide applications in photocatalyst, sensor, bioimaging and so on. In the present work, a novel kind of fluorine and nitrogen co-doped CDs (F,N-CDs) have been synthesized from 5-fluorouracil (5-Fu) and p-phenylenediamine (p-PD) via a hydrothermal method. An electrochemical sensor for detecting catechol was designed and constructed on the basis of F,N-CDs and laccase (Lac). Compared with the traditional detection methods of catechol, the as-fabricated sensor Lac-F,N-CDs/glassy carbon electrode (GCE) shows a comparatively low detection limit (0.014 μM) as well as a high sensitivity (219.17 μA cm−2 mΜ−1) through the amperometric i-t responses method. The most significant feature of the sensor is its long cycle stability and can be used for many times (≥50) under ambient conditions. The prepared Lac-F,N-CDs/GCE sensor has been employed for detection of catechol in tap water and lake water successfully. This work provides a new pathway to stabilize laccase by using CDs and other carbon nanomaterials to construct efficient electrochemical sensor for detecting catechol and its analogue.