High efficiency upconversion nanophosphors for high-contrast bioimaging.
Upconversion nanoparticles (UCNPs) are of interest because they allow suppression of tissue autofluorescence and are therefore visible deep inside biological tissue. Compared to upconversion dyes, UCNPs have a lower pump intensity threshold, better photostability, and less toxicity. Recently, YVO4: Er+3, Yb+3nanoparticles were shown to exhibit strong up-conversion luminescence with a relatively low 10 kW cm-2excitation intensity even in water, which makes them excellent bio-imaging candidates. Herein, we investigate their use as internal probes in insects by injecting YVO4: Er+3, Yb+3nanoparticles into fire ants as a biological model, and obtain 2D optical images with 980 nm illumination. High-contrast images with high signal-to-noise ratio are observed by detecting the up-conversion fluorescence as the excitation laser is scanned.
The National Center for Applied Physics, KACST, PO Box 6086, Riyadh 11442, Saudi Arabia. Institute for Quantum Science and Engineering (IQSE) and Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843-4242, USA.
Masfer H
MH
Alkahtani
Fahad S
FS
Alghannam
Carlos
C
Sanchez
Carmen L
CL
Gomes
Hong
H
Liang
Philip R
PR
Hemmer
D007834:Lasers; D049449:Luminescence; D053758:Nanoparticles; D010758:Phosphorus; D014867:Water
D014867:Water; D010758:Phosphorus