Development of an ultrasensitive spectrophotometric method for carmine determination based on fluorescent carbon dots

• Published in: Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment Vol. 38; no. 5; pp. 731 - 740
• Main Authors: Hu, Qin, Sun, Huijuan, Liu, Lingfei, Xiao, Lixia, Yang, Zhen-Quan, Rao, Shengqi, Gong, Xiaojuan, Han, Jie
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 04.05.2021; Taylor & Francis Ltd
• Subjects: Carbon dots; Carmine; Fluorescence; Food; Food additives; Food dyes; Food matrix; Food production; inner filter effect; N-doped carbon dots; Nitrogen; Phenylenediamine; Quenching; spectrophotometric method; Spectrophotometry; spectrophotometric method; N-doped carbon dots; Carmine; inner filter effect
• ISSN: 1944-0049; 1944-0057
• DOI: 10.1080/19440049.2021.1889045

A high-efficiency spectrophotometric method based on nitrogen-doped fluorescent carbon dots (N-FCDs) was developed for the ultrasensitive determination of carmine (CRM) in foodstuffs. The N-FCDs were fabricated via a one-pot hydrothermal method with m-phenylenediamine as the starting material. The detection principle was based on the fluorescence quenching effect of N-FCDs by CRM, where their interaction was due to the inner filter effect (IFE) and static quenching. A good linear relationship was established for CRM detection in a concentration range of 0.1-10.0 μM with a detection limit as low as 11.2 nM. The proposed method achieved satisfactory results for CRM determination in commercial food products with recoveries better than 98.6% and relative standard deviations (RSDs) less than 4.07%. The method established in this study was simple, ultrasensitive and reliable for rapid detecting CRM in a food matrix, which could be potentially used as a useful sensing agent for the analysis of additive food colourants.