Tunable lifetime multiplexing using luminescent nanocrystals

게시자: Hyung Min Kim, 2013. 12. 27. 오후 11:27   [ 2013. 12. 27. 오후 11:28에 업데이트됨 ]
 Optical multiplexing plays an important role in applications such as optical data storage1, document security2, molecular probes3, 4 and bead assays for personalized medicine5. Conventional fluorescent colour coding is limited by spectral overlap and background interference, restricting the number of distinguishable identities. Here, we show that tunable luminescent lifetimes τ in the microsecond region can be exploited to code individual upconversion nanocrystals. In a single colour band, one can generate more than ten nanocrystal populations with distinct lifetimes ranging from 25.6 µs to 662.4 µs and decode their well-separated lifetime identities, which are independent of both colour and intensity. Such ‘τ-dots’ potentially suit multichannel bioimaging, high-throughput cytometry quantification, high-density data storage, as well as security codes to combat counterfeiting. This demonstration extends the optical multiplexing capability by adding the temporal dimension of luminescent signals, opening new opportunities in the life sciences, medicine and data security.
Lifetime tuning scheme and time-resolved confocal images for NaYF4:Yb,Tm upconversion nanocrystals.
Nature Photonics 8, 32–36 (2014)