Silicon nanocrystals as handy biomarkers

Kouki Fujioka; Akiyoshi Hoshino; Noriyoshi Manabe; Yasuhiro Futamura; Richard Tilley; Kenji Yamamoto

doi:10.1117/12.699772

Translator Disclaimer

6 March 2007 Silicon nanocrystals as handy biomarkers

Kouki Fujioka, Akiyoshi Hoshino, Noriyoshi Manabe, Yasuhiro Futamura, Richard Tilley, Kenji Yamamoto

Author Affiliations +

Proceedings Volume 6448, Colloidal Quantum Dots for Biomedical Applications II; 644816 (2007) https://doi.org/10.1117/12.699772
Event: SPIE BiOS, 2007, San Jose, California, United States

Abstract

Quantum dots (QDs) have brighter and longer fluorescence than organic dyes. Therefore, QDs can be applied to biotechnology, and have capability to be applied to medical technology. Currently, among the several types of QDs, CdSe with a ZnS shell is one of the most popular QDs to be used in biological experiments. However, when the CdSe QDs were applied to clinical technology, potential toxicological problems due to CdSe core should be considered. To eliminate the problem, silicon nanocrystals, which have the potential of biocompatibility, could be a candidate of alternate probes. Silicon nanocrystals have been synthesized using several techniques such as aerosol, electrochemical etching, laser pyrolysis, plasma deposition, and colloids. Recently, the silicon nanocrystals were reported to be synthesized in inverse micelles and also stabilized with 1-heptene or allylamine capping. Blue fluorescence of the nanocrystals was observed when excited with a UV light. The nanocrystals covered with 1-heptene are hydrophobic, whereas the ones covered with allylamine are hydrophilic. To test the stability in cytosol, the water-soluble nanocrystals covered with allylamine were examined with a Hela cell incorporation experiment. Bright blue fluorescence of the nanocrystals was detected in the cytosol when excited with a UV light, implying that the nanocrystals were able to be applied to biological imaging. In order to expand the application range, we synthesized and compared a series of silicon nanocrystals, which have variable surface modification, such as alkyl group, alcohol group, and odorant molecules. This study will provide a wider range of optoelectronic applications and bioimaging technology.

Citation Download Citation

Kouki Fujioka, Akiyoshi Hoshino, Noriyoshi Manabe, Yasuhiro Futamura, Richard Tilley, and Kenji Yamamoto "Silicon nanocrystals as handy biomarkers", Proc. SPIE 6448, Colloidal Quantum Dots for Biomedical Applications II, 644816 (6 March 2007); https://doi.org/10.1117/12.699772

ACCESS THE FULL ARTICLE