A Dual-Mode Detection Sensor Based on Nitrogen-Doped Carbon Dots for Visual Detection of Fe(III) and Ascorbic Acid via a Smartphone

• Published in: Journal of fluorescence Vol. 35; no. 2; pp. 1125 - 1137
• Main Authors: Kayani, Kawan F., Abdullah, Chalak Najat
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.02.2025; Springer Nature B.V
• Subjects: Analytical Chemistry; Ascorbic acid; Ascorbic Acid - analysis; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedicine; Biophysics; Biotechnology; Carbon - chemistry; Carbon dots; Ferric Compounds - analysis; Fluorescence; Fluorescent Dyes - chemical synthesis; Fluorescent Dyes - chemistry; Limit of Detection; Nitrogen; Nitrogen - chemistry; Quantum Dots - chemistry; Smartphone; Smartphones; Spectrometry, Fluorescence; Synthesis; Ascorbic acid; Carbon dots; Fe(III) ion detection; Smartphone; Visual detection
• ISSN: 1573-4994; 1053-0509; 1573-4994
• DOI: 10.1007/s10895-024-03604-0

Accurately and promptly detecting Fe 3+ and ascorbic acid (AA) is a crucial objective. In this study, nitrogen-doped carbon dots (N-CDs) were synthesized using a one-step hydrothermal synthesis method with 6,9-diamino-2-ethoxyacridine lactate as the precursor. The introduction of Fe 3+ and AA resulted in both fluorescence (FL) quenching and enhancement of the synthesized N-CDs. The fluorescent response of the N-CDs probe to Fe 3+ was observed in the concentration range of 5–20 µM and 25–50 µM, with a limit of detection (LOD) of 290 nM. Remarkably, the fluorescence of the N-CDs was recovered upon the addition of AA to the N-CDs-Fe 3+ system. Using the “off-on” fluorescent N-CDs probe, a linear range of 40–90 µM was achieved with an LOD of 0.69 µM. Additionally, the feasibility of employing a smartphone equipped with an RGB Color Picker was demonstrated for the analysis of Fe 3+ and AA concentrations, providing a novel visual detection method. Furthermore, the application of N-CDs in solution demonstrated considerable potential for visually detecting Fe 3+ and AA. The proposed dual-mode detection sensor was found to be simple, efficient, and stable, enabling the successful determination of Fe 3+ and AA in practical samples with satisfactory results. Graphical Abstract