title: Upconversion: road to El Dorado of the fluorescence world.
abstract: Upconversion nanoparticles (UCNs), in the recent times have attracted attention due to their unique properties, which makes them ideal fluorophores for use in biological applications. There have been various reports on their use for targeted cell imaging, drug and gene delivery and also for diffuse optical tomography. Here we give a brief introduction on what are UCNs and the mechanism of upconversion, followed by a discussion on the biological applications of UCNs and further on what the future holds for UCNs.
authors.affiliation: Division of Bioengineering, Faculty of Engineering, National University of Singapore, 117576, Singapore.
authors.forename: Li Ching
authors.initials: LC
authors.lastname: Ong
authors.forename: Muthu Kumara
authors.initials: MK
authors.lastname: Gnanasammandhan
authors.forename: Sounderya
authors.initials: S
authors.lastname: Nagarajan
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002460:Cell Line; D005453:Fluorescence; D006801:Humans; D008163:Luminescent Measurements; D053758:Nanoparticles / Q000737:chemistry*; D017785:Photons; D045663:Quantum Dots; D051381:Rats