Abstract
The cytotoxicity of hydrophobic QDs CdS/CdSe was tested assigning MTT assay on Human Embryonic Kidney cells (HEK-293), breast cancer cells (MCF-7) and Enrichlish Ascitices Cells (EAC). Approximately 65% bio-toxicity was observed in MCF-7 for the core-shell QDs. These QDs may also find effective applications in other optoelectronic devices. CdS/CdSe core-shell hetrostructure quantum dots (QDs) were generated by chemical reaction between the respective chalcogens and cadmium metal salt. Sulphur powder was utilized for CdS core preparation while selenium was extracted from an organoselenium compound to impart CdSe shell layer at a temperature between 150℃ - 200℃. So-prepared core-shell QDs showed good optical properties. The particle size was found to be in the range of 3 - 4 nm with spherical morphology and cubic crystal structure.
Highlights
Amongst II-VI quantum dots (QDs), CdS, ZnSe, CdSe and core-shell type e.g. ZnSe/CdS, CdS/CdSe etc. are documented to be important for photonics and biomedical applications because of their inorganic nature which offers good environmental and photostability as well as chemical inertness
We have recently reported synthesis and characterization of ZnSe/CdSe coreshell quantum dots and its relation with size and optical properties [12]
As shell grows around CdS core both absorption and emission wavelength show systematic red-shifts i.e. shifts towards the longer wavelength, indicative of formation of larger particle possibly due to clustering. This red-shift can be correlated with decrease in band gap of CdSe due to the formation of CdS/CdSe core-shell. Such observations are quite handy in termination of chemical reaction during the synthesis and assuming that the right optical quality has been obtained for the QDs that can be exploited for biological as well other electronic applications including optical sensor applications
Summary
Amongst II-VI QDs, CdS, ZnSe, CdSe and core-shell type e.g. ZnSe/CdS, CdS/CdSe etc. are documented to be important for photonics and biomedical applications because of their inorganic nature which offers good environmental and photostability as well as chemical inertness. The surfactants such as long chain carboxylic acids, alkyl or aryl amines and low molecular weight polymers normally are employed to improve the quality of quantum dots for a variety of applications Another option to alter the surface is by coating of same group QDs as a shell upon inorganic core called core-shell structures such as CdSe/CdS [3], CdSe/ZnS [4], CdSe/CdTe [9], CdSe/ZnSe [10], CdTe/CdSe [11]. Zhang et al [20] studied effect of nitrogen doped carbon QDs on living (Hela) cell and as selective probe for Fe. In the current work we assigned MTT assay on MCF-7, HEK-293 and EAC cell lines and evaluated internalization as well as cellular uptake induced biotoxicity by use of CdS/CdSe QDs. Previously our group reported synthesis of CdSe, ZnSe and ZnSe/CdSe QDs by using cyclohexeno1,2,3-selenadiazole where in it was shown that cyclohexeno-1,2,3-slenadiazole can be used effectively for synthesis of various types of chalcogenide based QDs including core-shell nano-structures [12]. Internalization of cellular induced biotoxicity assigning MTT assay on anti cancer HEK-293, MCF-7 and EAC cell lines was studied
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
