Abstract
In this work, carbon quantum dots (CQDs) were synthesized by microwave irradiation and were electropolymerized on glassy carbon electrode (GCE) to establish an electrochemical sensor for the selective detection of ascorbic acid (AA). Electrochemical behaviors of the prepared sensor were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Herein, two wide linear responses were obtained in ranges of 0.01-3 mM and 4-12 mM with a low detection limit of 10 μM to AA. High sensitivities (44.13 μA-1 μM-1 cm-2, 9.66 μA-1 μM-1 cm-2, respectively) corresponding to the linear ranges were also achieved. In addition, the electrochemical sensor exhibited good selectivity and robust anti-interference ability toward AA in the presence of dopamine (DA) and uric acid (UA). These results showed that this sensor can be used as a promising tool to detect AA in real complex systems.
Highlights
IntroductionAscorbic acid (vitamin C, ascorbic acid (AA)) plays a crucial role as an essential nutrient and antioxidant in the human body, which exists only in food and drugs and cannot be synthesized by human beings themselves
Ascorbic acid plays a crucial role as an essential nutrient and antioxidant in the human body, which exists only in food and drugs and cannot be synthesized by human beings themselves
ascorbic acid (AA) was purchased from Lianxing Biotechnology (Tianjin), polyethylene glycol-200 was bought from Beijing Solarbio Science & Technology, dopamine hydrochloride was purchased from Sigma-Aldrich, uric acid (UA) was obtained from Ron Chemical Reagent Company (Tianjin), glucose was obtained from Tianjin Yingda Xigui Chemical Reagent Factory, and 0.1 M phosphate buffer solution (PBS) was prepared by mixing a proper proportion of Na2HPO4 and NaH2PO4
Summary
Ascorbic acid (vitamin C, AA) plays a crucial role as an essential nutrient and antioxidant in the human body, which exists only in food and drugs and cannot be synthesized by human beings themselves. Methods synthesizing the CQDs have been studied extensively, such as hydrothermal [35], laser ablation [36], ultrasonic [37], microwave synthesis [38], and solvothermal [39]. We have developed a sensor for AA determination based on CQDs, which were synthesized using glucose as the carbon source and polyethylene glycol-200 as the surface passivator through a one-step facile microwave approach. This fabricated CQD electrode demonstrated wider linear ranges and higher sensitivity toward AA compared to other modified electrodes based on electrochemical strategies. We envision that a CQD-based sensor will become a crucial platform for determination of AA in a complex system in the future
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
