Red-emissive carbon dot as fluorescent probe for the sensitive detection of sunset yellow in foodstuffs

• Published in: Food chemistry 2025-01, Vol.463 (Pt 4), p.141477, Article 141477
• Main Authors: Zhang, Qianchun, Ao, Yongxia, Liu, Jiaxin, Tang, Shan, Tian, Fengling, Tian, Xiaofang, Luo, Xinyu, Xie, Meijie
• Format: Article
• Language: English
• Subjects: Azo Compounds - analysis; Azo Compounds - chemistry; Benzil; Beverages - analysis; Carbon - chemistry; Citric acid; Fluorescent Dyes - chemistry; Food Analysis; Food Coloring Agents - analysis; Food Contamination - analysis; Foodstuffs; Limit of Detection; Polyethyleneimines; Quantum Dots - chemistry; Red-emissive carbon dots; Spectrometry, Fluorescence - methods; Sunset yellow
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2024.141477

The highly efficient red-emissive carbon dots (R-CDs) were synthesized from citric acid, polyethyleneimine, and benzil via a facile solvothermal process. The R-CDs displayed maximum fluorescence properties at excitation and emission wavelengths of 550 and 631 nm, respectively, which fall within the red wavelength range. Moreover, the R-CDs exhibited a high fluorescence quantum yield of 11.3 %, and this fluorescence was effectively quenched by Sunset Yellow (SY). Consequently, a novel fluorescent probe was developed for SY detection. This probe exhibited a linear range of 0.085–11.31 μg/mL and limit of detection of 0.026 μg/mL. The R-CDs were validated for SY quantification in various food samples, including carbonate beverages, powdered beverage, cider vinegar, fruit flavored drinks, chocolate, and hard candy samples, achieving recovery rates of 91.2–122 % and a relative standard deviation of 1.0–3.5 %. The synthesized R-CDs therefore show promise for application as a probe for the detection of SY in foods. •A novel red-emissive carbon dots (R-CDs) were synthesized through a facile method.•The developed method based on R-CDs was successfully validated for sunset yellow quantification in complex samples.•The R-CDs probe is highly selective and sensitive for sunset yellow, showcasing their potential in food safety analysis.