Takhar, VishakhaVishakhaTakharSingh, SimranjitSimranjitSinghMisra, Superb K.Superb K.MisraBanerjee, RupakRupakBanerjee2025-08-312025-08-312024-09-1310.1039/d4na00505h2-s2.0-85204725911http://repository.iitgn.ac.in/handle/IITG2025/28741MoS<inf>2</inf> quantum dots (MQDs) with an average size of 1.9 ± 0.7 nm were synthesized using a microwave-assisted method. Absorbance studies confirmed characteristic transitions of MoS<inf>2</inf>, with absorption humps at 260-280 nm and 300-330 nm, and a band gap of 3.6 ± 0.1 eV. Fluorescence emission studies showed dominant blue and some green emissions under 315 nm excitation, with an absolute quantum yield of ∼9%. The MQDs exhibited fluorescence stability over time after repeated quenching cycles across various pH and media systems. In vitro toxicity tests indicated cytocompatibility, with around 80% cell survival at 1000 mg L<sup>−1</sup>. Confocal imaging demonstrated significant uptake and vibrant fluorescence in cancerous and non-cancerous cell lines. The MQDs showed strong selectivity towards Fe<sup>3+</sup> ions, with a detection limit of 27.61 ± 0.25 nM. Recovery rates for Fe<sup>3+</sup> in phosphate buffer saline (PBS) and simulated body fluid (SBF) systems were >97% and >98%, respectively, with a relative standard deviation (RSD) within 3%, indicating precision. These findings suggest that MQDs have high potential for diagnostic applications involving Fe<sup>3+</sup> detection due to their fluorescence stability, robustness, enhanced cell viability, and dual-channel imaging properties.truel-cysteine capped MoS2 QDs for dual-channel imaging and superior Fe3+ ion sensing in biological systemsArticlehttps://doi.org/10.1039/d4na00505h251602305694-570713 September 20242arJournal2WOS:001317140900001