Luminescent carbon quantum dots derived from syzygium cumini seeds with endogenous anti-oxidant and cytotoxic potency including in vitro photoluminescence and live cell imaging

Abstract

This study focuses on the use of carbon quantum dots (CQDs) from Syzygium cumini seeds prepared through hydrothermal synthesis for anti-oxidant, bioimaging, and anti-neoplastic activities. Syzygium cumini seeds were incorporated with various biomass-sourced precursors to enhance their physicochemical properties, and doping of folic acid was performed to create surface passivated folate receptors for better anti-neoplastic activity exhibiting minimal toxicity, excellent biocompatibility, outstanding luminosity, and optical features. The concentration of CQDs required to inhibit the proliferation of cells by 50% (at 500 μg mL⁻¹ concentration) was calculated by applying the dose–response curve applied to the HeLa cell line, and the conclusion was computed by means of an augmented mimicking approach, leading to roughly identical inhibition by folic acid doped S. cumini seeds (40.926%) and doxorubicin (DOX) (43.39%) justifying better anti-neoplastic activity. The anti-oxidant potency of the prepared CQDs was assessed to be exceedingly excellent, with an index of up to 98.99%, implying resilient surface passivation. CQDs utilized for in vitro photoluminescence and live cell imaging of S. cerevisiae displayed green and blue fluorescence images with stabilized luminescence with extraordinary quantum yield (50.74%).