Sustainable carbon dots from Borreria hispida: enhanced colorimetric sensing of Fe3+ ions and biological applications in live cell imaging

Abstract

This study presents the synthesis of advanced nanomaterials derived from the hedge-grown herbal plant, Borreria hispida, and explores their environmental and biological applications. Using a one-step hydrothermal synthesis method, carbon dots derived from Borreria hispida (BHCD) were fabricated and thoroughly characterized through XRD, TEM, FTIR, CHNS, UV-visible, and PL spectroscopy analyses. Under UV illumination, these plant-based carbon dots demonstrated exceptional water solubility, notable photo stability, and a high quantum yield of 40.8%. The average particle size of BHCD was absorbed around 0.5 to 3.5 nm, contributing to superior selectivity and sensitivity in detecting Fe³⁺ ions, with a limit of detection of 1.2 × 10⁻⁶ M. Investigation into the sensing mechanism revealed a binding model wherein two carbon atom molecules bind to one Fe³⁺ atom in a 2 : 1 ratio for BHCDs and Fe³⁺ interactions. Additionally, the effectiveness of the developed fluorescent probe for Fe³⁺ detection was validated using real water samples from ponds and lakes, highlighting its potential for environmental monitoring applications. Furthermore, the biological effects of BHCD were evaluated through cytotoxic assays, demonstrating significant inhibitory effects on MCF7 breast cancer cell lines, with a maximum cell viability of 60%. This research underscores the multifaceted potential of BHCD in environmental monitoring and biomedical applications.