Synthesis and Optical Properties of Functionalized ZnS Quantum Dots for Cancer Detection

A heavy-metal-free luminescent quantum dot(QD) based on doped zinc sulfide(ZnS),conjugated with a cancer-targeting ligand, Mercaptoacetic acid (MAA), is presented asa promising bio-friendly system for target-ed cancer imaging. QDs were prepared by a simpleaqueous method at room temperature. X-ray diffrac-tion and transmission electronmicroscopy studies showed the formation of monodisperse QDs of average size∼4 nm withcubic (sphalerite) crystal structure. the QDs with resulted in multi-color emission with specificcolor tenability ranging from blue (280 nm) to red (352 nm). Luminescent centers in QDscould be excited us-ing bio-friendly visible light>400 nm by directly popu-lating the centers,leading to bright emission.. The bright and stable luminescence of the QDs could be used toimage both single cancer cells and colonies of cancer cells without affecting their metabolicactivity and morphology. Thus, this study presents the use of non-toxic, Cd-, Te-, Se-, Pb- andHg-free luminescent QDs for targeted cancer imaging.

کلیدواژه ها:

Quantum Dots ، ZnS ، MAA (Mercaptoacetic Acid) ، Cancer ، Functionalized