Highly Photoluminescent Carbon Dots Derived from Discarded Chewing Gum: toward Multiple Sensing of pH, Ferric Ion, and Adenosine Triphosphate

Abstract

In this paper, we develop a sustainable strategy to reuse discarded chewing gum for low‐cost synthesis of carbon dots (CDs) via a H2O2‐assisted hydrothermal method. The as‐prepared CDs have a large photoluminescence (PL) quantum yield (QY) of up to 25.7%, much higher than the most values of waste‐derived CDs. Interestingly, the PL intensity of CDs increases linearly as pH rises from 1 to 6, demonstrating the possibility of CDs for accurate pH monitoring in acidic conditions. It is suggested that the pH‐responsive PL feature is induced by the protonation and deprotonation of the surface oxygenous groups of CDs. Through the fluorescence quenching and recovery processes, the CDs can serve as a selective and sensitive sensor for sequential detection of ferric ion (Fe3+) and adenosine triphosphate (ATP) with limit of detection (LOD) as low as 0.028 and 0.003 μM, respectively. A possible electron transfer process is proposed to elucidate the sensing mechanism. For real applications, the CD sensing platform is successfully employed to determinate pH in natural stream, Fe3+ in tap water, and ATP in erythrocyte sample.

Detection of Fe3+ and Hg2+ Ions by Using High Fluorescent Carbon Dots Doped With S And N as Fluorescence Probes

“…As a new type of uorescent probe. Carbon quantum dots can be used to detect various metal ions because of their photoluminescence and high selectivity for metal ions [11][12][13][14][15]. Besides, the CDs has following advantages, low toxicity, good chemical stability [16], environment-friendly and light-resistant bleaching [17], which makes it attract wide attention by researchers.…”

Thermosensitive Fluorescent Microgels for Selective and Sensitive Detection of Fe3+ and Mn2+ in Aqueous Solutions

“…Regarding Fe 3+ and Mn 2+ ions, the long-term exposure to excessive levels of these heavy metal ions could cause numerous discomforts and diseases, such as vomiting, convulsions, Alzheimer’s disease, carcinoma, and even death, although Fe 3+ and Mn 2+ ions play vital roles in a series of critical biotic processes, including intracellular metabolism, DNA synthesis, enzymatic transformation, and the balance of catalytic cycle. Several fluorescent sensors have been constructed for detecting Fe 3+ ions in aqueous solutions. − For example, Li et al reported the dendrimer PYTPAG2 as a fluorescently quenched sensor for the detection of Fe 3+ ions in solution. The PYTPAG2 is composed of the interior core of pyrene and the exterior periphery of triphenylamine, which processes stable sensitivity and selectivity toward Fe 3+ ions in solution with a detection limit ( D L ) of 5.0 × 10 –7 M. Ma et al prepared monodispersed fluorescent MoS 2 quantum dots (QDs) for Fe 3+ detection with a D L of 1 μM in the concentration range 0–50 μM.…”

Fluorescent Nanoscale Covalent Organic Frameworks with the Theoretically Matched Redox Potential of Fe3+/Fe2+ for Monitoring of Adenosine-5′-Triphosphate in Cells

“…The detection limit was calculated to be 0.0024 μM in the range of 0.005–5.0 μM, which showed higher sensitivity than other ATP fluorescent sensors (Table S2). ,,− Moreover, it can be obtained through the labeled recovery experiment in ultrapure water and human serum (Table S3). The probe has a good anti-interference ability for the detection of ATP with good sensitivity and specificity.…”