Mechanochemical approach for the capping of mixed core CdS/ZnS nanocrystals: Elimination of cadmium toxicity.
The wet mechanochemical procedure for the capping of the CdS and CdS/ZnS quantum dot nanocrystals is reported. l-cysteine and polyvinylpyrrolidone (PVP) were used as capping agents. When using l-cysteine, the dissolution of cadmium(II) was almost none for CdS/ZnS nanocrystals. Moreover, prepared CdS- and CdS/ZnS-cysteine nanosuspensions exhibited unimodal particle size distributions with very good stability, which was further supported by the zeta potential measurements. The Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy showed the successful embedment of cysteine into the structure of the nanocrystals. Additionally, the optical properties were examined, and the results showed that the cysteine nanosuspension has promising fluorescence properties. On the other hand, PVP was not determined to be a very suitable capping agent for the present system. In this case, the release of cadmium(II) was higher in comparison to the l-cysteine capped samples. The nanosuspensions were successfully used for in vitro studies on selected cancer cell lines. Using fluorescence microscopy, it was evidenced that the nanocrystals enter the cell and that they can serve as imaging agents in biomedical applications.
Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 04001 Košice, Slovakia. Electronic address: bujnakova@saske.sk.
Zdenka
Z
Bujňáková
Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 04001 Košice, Slovakia. Electronic address: balazm@saske.sk.
Matej
M
Baláž
Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 04001 Košice, Slovakia. Electronic address: dutkova@saske.sk.
Erika
E
Dutková
Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 04001 Košice, Slovakia. Electronic address: balaz@saske.sk.
Peter
P
Baláž
Faculty of Medicine, P. J. Šafárik University, Trieda SNP 1, 04011 Košice, Slovakia. Electronic address: martin.kello@upjs.sk.
Martin
M
Kello
Faculty of Medicine, P. J. Šafárik University, Trieda SNP 1, 04011 Košice, Slovakia. Electronic address: gabriela.mojzisova@upjs.sk.
Gabriela
G
Mojžišová
Faculty of Medicine, P. J. Šafárik University, Trieda SNP 1, 04011 Košice, Slovakia. Electronic address: jan.mojzis@upjs.sk.
Ján
J
Mojžiš
Faculty of Science, P. J. Šafárik University, Moyzesova 11, 04001 Košice, Slovakia. Electronic address: maria.vilkova@upjs.sk.
Mária
M
Vilková
Faculty of Science, P. J. Šafárik University, Moyzesova 11, 04001 Košice, Slovakia. Electronic address: jan.imrich@upjs.sk.
Ján
J
Imrich
Faculty of Science, P. J. Šafárik University, Moyzesova 11, 04001 Košice, Slovakia; Biomedical Research Centre, University Hospital Hradec Kralove, Sokolska 581, 50005 Hradec Kralove, Czech Republic. Electronic address: miroslav.psotka@gmail.com.
Miroslav
M
Psotka
D001692:Biological Transport; D018938:Caco-2 Cells; D019187:Cadmium Compounds / Q000737:chemistry* / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D003287:Contrast Media / Q000737:chemistry* / Q000494:pharmacology; D003545:Cysteine / Q000737:chemistry*; D004058:Diffusion; D005453:Fluorescence; D045325:HCT116 Cells; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D061986:MCF-7 Cells; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011205:Povidone / Q000737:chemistry*; D045663:Quantum Dots / Q000737:chemistry / Q000648:ultrastructure; D013440:Sulfides / Q000737:chemistry* / Q000494:pharmacology; D013499:Surface Properties; D013535:Suspensions; D017967:Zinc Compounds / Q000737:chemistry* / Q000494:pharmacology
D019187:Cadmium Compounds; D003287:Contrast Media; D013440:Sulfides; D013535:Suspensions; D017967:Zinc Compounds; C034939:cadmium sulfide; D011205:Povidone; D003545:Cysteine; C031238:zinc sulfide
Capping; CdS/ZnS nanocrystals; Mechanochemistry; Polyvinylpyrrolidone; Toxicity; l-cysteine