resumo
Luminescent TbPO4 nanoparticles were synthesized via a citric-acid-mediated hydrothermal route. Eu3+ doping of TbPO4 enables an efficient Tb3+-to-Eu3+ energy transfer, leading to a four-fold increase of the absolute emission quantum yield (QY), compared to that of undoped TbPO4. To check the potential of biological use, we conducted in vitro biological experiments on human cervical carcinoma HeLa cells incubated with TbPO4:Eu nanoparticles. TbPO4:Eu nanoparticles can be successfully internalized into the cells, and they show bright intracellular luminescence and very low cytotoxicity. Photoluminescence intensity dependence upon time demonstrates that Eu3+-doped TbPO4 nanoparticles are highly resistant to photobleaching. Our present work represents a demonstration of the use of rare-earth-based nanocrystals as a biological labeling agent because they combine several advantages including high emission quantum yield, long luminescence lifetime, low cytotoxicity and high photostability.
palavras-chave
NANOCRYSTALS; MORPHOLOGY; NANOWIRES; NANORODS; PROBES
categoria
Chemistry; Science & Technology - Other Topics; Materials Science; Physics
autores
Di, WH; Li, J; Shirahata, N; Sakka, Y; Willinger, MG; Pinna, N
nossos autores
Nicola Pinna
InvestigadorGrupos
Projectos
Nanostructured Photoluminescent rare-earth nanotubes and microporous silicates (PTDC/CTM/73243/2006)
agradecimentos
This study was partly supported by the Grant-in Aid for Scientific Research of the JSPS and the World Premier International Research (WPI) Center Initiative on Materials Nanoarchitronics (MANA), MEXT, Japan, the WCU (WorldClass University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R31-10013) and FCT project (PTDC/CTM/73243/2006). NS wishes to thank the JST PRESTO program for financial support.