Fluorometric Determination of Fe3+ Ions using Carbon Dots Prepared from the Extract of Singapore Cherry

The development of affordable and ecologically acceptable technologies for heavy metal detection and removal is required due to the rising levels of water and soil pollution. Carbon Dots (CDs) have emerged as a promising nanomaterial for heavy metal detection due to their unique properties. In this study, we report a simple and eco-friendly method to produce CDs using Muntingia calabura fruit extract as a precursor. The hydrothermal method produced a well-defined size, structure, and optical properties of CDs, which were analyzed by using various characterization techniques, including Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray Spectroscopy (EDS), Elemental mapping (E-map), UV-visible spectroscopy, X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), Photoluminescence (PL) spectroscopy, and Transmission Electron Microscopy (TEM). Additionally, Zeta potential and DLS analysis were used to characterize the CDs. As-synthesized CDs exhibited strong fluorescence emission, making them suitable for the selective determination of Fe3+ ions. The detection limit was found to be 3.6 μM for Fe3+ ions, which highlighted the potential application of as-prepared CDs in environmental monitoring. The green synthesized CDs from Muntingia calabura fruit extract provided a sustainable approach for developing efficient nanoprobes for detecting Fe3+ ions in environmental and biological samples.