Development
of the fluorophores whose fluorescence bands can be
flexibly selected is of great interest for biotissue imaging. Compounds
of Ag+:MgS, Ag+:Nb2S5,
Sm3+:Y2S3, Sm3+:Er2S3, and Sm3+:ZrS2 were obtained
through new chemical synthesis. They were characterized by X-ray photoelectron
spectroscopy, X-ray diffraction spectroscopy, and transmission electron
microscopy. They revealed polychromatic-photoluminescence spectra
when excited by 280, 380, 480, 580, 680, and 785 nm light. Especially,
near-infrared emission ranging from 800–1100 nm was found upon
785 nm light excitation. A band model was proposed to explain transitions
responsible for the observed components of emission. Their broad fluorescence
spectra cover from the ultraviolet to near-infrared spectral range.
Their ability of emitting wide-range fluorescence was utilized for
multicolor fluorescence imaging of biotissues, as demonstrated by
pig-kidney tissue samples.