Synthesis of molybdenum nanoclusters from Vitex negundo leaves for sensing epinephrine in a pharmaceutical composition

Abstract

The fabrication of metal nanoclusters (NCs) obtained from medicinal plant extracts for the detection of biomolecules has attracted a lot of interest recently. In this work, green chemistry is used to synthesize cyan fluorescent molybdenum nanoclusters (MoNCs) for the selective detection of epinephrine. The MoNCs were synthesized by using MoCl₅ as a metal precursor and Vitex negundo (V. negundo) plant extract as a capping agent. With the addition of epinephrine, the intensity of the emission peak of V. negundo-MoNCs at 495 nm was drastically quenched (68%) on the basis of the inner filter effect (IFE) between V. negundo-MoNCs and epinephrine demonstrating that V. negundo-MoNCs can be used as sensing probe for the epinephrine detection. Further, the effect of pH on the fluorescence response of V. negundo-MoNCs was investigated for sensing epinephrine. Moreover, the V. negundo-MoNCs fluorescent probe exhibited a good linear range of (0.25–10 μM) for epinephrine with a detection limit of 0.46 μM. The MTT assay was used to investigate the cytotoxicity of V. negundo-MoNCs on the A549 lung cancer cell line, demonstrating the biocompatibility of MoNCs. This approach was further successfully employed for quantifying epinephrine in pharmaceutical samples.