Green preparation of silanized carbon dots with ficus virens leaves as a potent antibacterial agent and an effective fluorescent sensor of iron ion

In this work, a green and economical strategy to prepare silanized carbon dots (Si-CDs) based on Ficus virens leaves was carried out. The prepared difunctional Si-CDs showed high water-solubility and favorable photostability. The morphology and surface functional groups were analyzed by TEM, FT-IR, and XPS. Si-CDs had amorphous nature with no crystal lattice and the average diameter of 1.95 nm. Some functional groups like nitrogen groups , oxygen groups, and silicon groups were discovered. Attributing to the small size of Si-CDs, positive charges, and the generation of singlet oxygen and hydrogen radicals, Si-CDs possessed effective antibacterial activity . The minimum inhibitory concentration of Si-CDs against Escherichia coli and Staphylococcus aureus was 0.078 mg/mL. Moreover, Si-CDs exhibited selective and sensitive fluorescence quenching response to Fe 3+ through static quenching process. The limit of detection was 0.84 μmol/L in the liner range of 5–50 μmol/L. Analysis of real samples led to 99.8–102.0% recoveries and <1% relative standard deviation. Consequently, this work discovered a new, green, economical silanized carbon dot with the potential application as a potent antibacterial agent and an effective fluorescent sensor of iron ion .