A phosphine oxide compound represented by the following formula (I) and a rare earth complex containing the same are disclosed:

##STR00001## wherein n represents an integer of 3 or more, Ar.sup.1 represents an n-valent aromatic group, L represents a divalent linker group, and Ar.sup.2 and Ar.sup.3 each independently represent a monovalent aromatic groups.

A double fluorescent particle comprises: a core with a first fluorescence; and a molecularly imprinted polymer (MIP) shell with a second fluorescence; wherein the MIP is an organic polymer comprising elements selected from the group consisting of: C, H, O, N, P, and S; wherein the MIP is adapted to selectively bind to a cell surface structure; wherein the first fluorescence is generated by an entity selected from the group consisting of: a carbon nanodot, an alkaline earth metal fluoride, a dye-doped polymer, a dye-doped stabilized micelle, a P-dot—i.e. a π-conjugated polymer, a quantum dot doped polymer, a rare earth metal ion doped polymer, a dye-doped silica, a rare-earth ion doped silica, and a rare earth ion doped alkaline earth metal fluoride nanoparticle; wherein the second fluorescence is generated by an entity selected from the group consisting of: a dye, a molecular probe, an indicator, a probe monomer, an indicator monomer, and a cross-linker, and wherein the first and second fluorescence differ at least by an emission wavelength and/or by an excitation wavelength.

Luminescent compositions are provided having improved color intensity and articles incorporating said luminescent compositions as security taggants, for example as anti-counterfeiting components in pharmaceutical packaging applications, or as aesthetic colorants that are generally usable in any application where luminescent coloration is desired. The luminescent compositions incorporate a particulate fluoropolymer that is blended with one or more luminescent pigments and/or luminescent dyes. These components are provided in a liquid medium in which the fluoropolymer particles are dispersed and with which the pigment(s)/dye(s) may or may not be soluble.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.

Embodiments described herein generally relate to: sensing and/or authentication using luminescence imaging; diagnostic assays, systems, and related methods; temporal thermal sensing and related methods; and/or to emissive species, such as those excitable by white light, and related systems and methods.