Spectroscopic characterization of upconverting phosphor reporters

摘要

We examined the spectroscopic properties of a novel class of reporters for biomedical diagnostics called upconverting phosphors. These materials exhibit high emission efficiencies, extremely low background levels, no photobleaching, minimal phototoxicity and a variety of emission bands suitable for multi-analyte assays. In addition, they are buffer insensitive and can be excited with inexpensive and compact diode lasers. These properties are very useful for immunoassays, nucleic acid assays, in vivo diagnostics, and other applications. We synthesized submicron monodisperse phosphors and measured the emission spectra, excitation spectra, and power dependencies for a variety of phosphor materials containing different active rare earth ions and host materials. In this paper, we discuss the relation between spectral properties and diagnostic applications.