Encapsulation of thymol and menthol loaded N/S co-doped carbon dots derived from a mixture of herbal extracts as theranostic agents with anticancer properties

Abstract

This research was conducted by synthesizing carbon dots MNE-CDs (mixed natural extract-carbon dots) based on mixed natural extract (ginger, garlic, turmeric) through the hydrothermal routh. Menthol and thymol were loaded as multi-therapeutic drugs with the addition of the bio-enhancer loaded on MNE-CDs with the hydrothermal method during a separate stage. These nanostructures were successfully encapsulated in chitosan by the nanospray drying method to enhance sustainability and release control. This study answered three of these issues by fabricating novel carbon dots for anticancer potential, release behavior and bioimaging at the same time. Preparation carbon dots are characterized using UV–vis, PL, FE-SEM, DLS, EDX, and FT-IR analysis. A moderate and sustained release profile of encapsulated carbon dots was noticed in comparison to the free carbon dots over 48 h of study in both simulated physicological environment (pH 7.4) and tumor tissue (pH 5.2) conditions. It was found that the release of bioactive substances from encapsulated samples was significantly attenuated. The cell viability assay showed all the samples, including free and encapsulated carbon dots, offered acceptable cytotoxicity against MCF-7 breast cancer cells. Despite this, the toxicity of free carbon dots is more than the encapsulated samples, and also the enhancement in anticancer potential was not observed for carbon dots loaded with menthol and thymol. Upon the obtained results, the synthesized fluorescence N/S co-doped carbon dots hold great anticancer potential and biological fluorescent labeling.