High-yield red fluorescent carbon dots for turn-on detection of Fe3+ and multicolor cell imaging

Novel red carbon nanodots (R-CDs) have been specifically constructed and employed as an innovative fluorescent “turn-on” probe enabling sensitive detection of Fe 3+ ions. Novel R-CDs with a 70% yield were produced through a hydrothermal approach using erythromycin and L-isoleucine as precursor materials. The resultant R-CDs exhibit a rich functional groups, excellent water solubility, minimal cytotoxicity, remarkable fluorescence stability, and favorable biocompatibility. Remarkably, the R-CDs demonstrated a remarkable increase in fluorescence intensity following the addition of Fe 3+ which can be attributed to the aggregation-induced emission (AIE) enhancement mechanism. The linear range of Fe 3+ detected by R-CDs is 2.1–37.5 μM, with a detection limit of 0.17 ± 0.02 μM. This approach has also been effectively utilized for the precise analysis of actual samples. Furthermore, R-CDs demonstrate applicability in multicolor cellular imaging and the detection of intracellular Fe 3+ . The findings indicate that the obtained R-CDs exhibit considerable application prospects in sensing and biomedical domains.