Patent ID: 7501092

Claim:
A method of using a bioconjugated upconversion luminescent nanoparticle system for biological labeling, comprising the steps of: delivering a bioconjugated upconversion luminescent nanoparticle system to a target, binding the bioconjugated upconversion luminescent nanoparticle system to the target, and measuring upconversion luminescence from the bioconjugated upconversion luminescent nanoparticle system bound to the target, wherein an emission wavelength of the bioconjugated upconversion luminescent nanoparticle is shorter than an excitation wavelength of the bioconjugated upconversion luminescent nanoparticle, wherein the upconversion luminescent nanoparticle of the bioconjugated upconversion luminescent nanoparticle system has the general formula (X):(Mn, R), wherein (X) is a host having a size less than 100 nm and is represented by the formula (M 1-z N z ) 1-x A 1-y B y where M=Zn, Cd, Pb, Ca, Ba, Sr, and Mg; N=Zn, Cd, Pb, Ca, Ba, Sr, and Mg; A=S, Se, Te, and O; B=S, Se, Te, and O, wherein 0≦x<1, 0<y≦1, 0<z≦1, and (R) is a rare earth ion.