The invention generally relates to materials and methods for creating and/or utilizing upconverting luminescence. More particularly, the invention relates to novel compositions (e.g., nanoparticles) and related methods of preparation and use that enable upconverting luminescence with an efficient excitation optimized at about 800 nm. A unique class of cascade sensitized tri-doped UCNPs with a biocompatible 800 nm excitable property are disclosed herein, for example, tri-doped -NaYF.sub.4:Nd,Yb,Er(Tm)/NaYF.sub.4 UCNPs, which employ Nd.sup.3+ as 800 nm photon sensitizer and Yb.sup.3+ as bridging ions, having strong green or blue upconversion emissions without photobleaching.

A scintillation crystal can include Ln.sub.(1-y)RE.sub.yX.sub.3, wherein Ln represents a rare earth element, RE represents a different rare earth element, y has a value in a range of 0 to 1, and X represents a halogen. In an embodiment, the scintillation crystal is doped with a Group 1 element, a Group 2 element, or a mixture thereof, and the scintillation crystal is formed from a melt having a concentration of such elements or mixture thereof of at least approximately 0.02 wt. %. In another embodiment, the scintillation crystal can have unexpectedly improved proportionality and unexpectedly improved energy resolution properties. In a further embodiment, a radiation detection apparatus can include the scintillation crystal, a photosensor, and an electronics device. Such a radiation detection apparatus can be useful in a variety of applications.

Monodisperse particles having: a single pure crystalline phase of a rare earth-containing lattice, a uniform three-dimensional size, and a uniform polyhedral morphology are disclosed. Due to their uniform size and shape, the monodisperse particles self assemble into superlattices. The particles may be luminescent particles such as down-converting phosphor particles and up-converting phosphors. The monodisperse particles of the invention have a rare earth-containing lattice which in one embodiment may be an yttrium-containing lattice or in another may be a lanthanide-containing lattice. The monodisperse particles may have different optical properties based on their composition, their size, and/or their morphology (or shape). Also disclosed is a combination of at least two types of monodisperse particles, where each type is a plurality of monodisperse particles having a single pure crystalline phase of a rare earth-containing lattice, a uniform three-dimensional size, and a uniform polyhedral morphology; and where the types of monodisperse particles differ from one another by composition, by size, or by morphology. In a preferred embodiment, the types of monodisperse particles have the same composition but different morphologies. Methods of making and methods of using the monodisperse particles are disclosed.

The invention relates to a microarray design of hybrid upconversion nanoparticles on a nanoporous anodized alumina membrane heterogeneous assay for simultaneous detection of multiple oligonucleotides, for example, oligonucleotides from different types of viruses.

The present disclosure relates to a process for fabricating a crystalline scintillator material with a structure of elpasolite type of theoretical composition A.sub.2BC.sub.(1-y)M.sub.yX.sub.(6-y) wherein: A is chosen from among Cs, Rb, K, Na, B is chosen from among Li, K, Na, C is chosen from among the rare earths, Al, Ga, M is chosen from among the alkaline earths, X is chosen from among F, Cl, Br, I,
y representing the atomic fraction of substitution of C by M and being in the range extending from 0 to 0.05, comprising its crystallization by cooling from a melt bath comprising r moles of A and s moles of B, the melt bath in contact with the material containing A and B in such a way that 2s/r is above 1. The process shows an improved fabrication yield. Moreover, the crystals obtained can have compositions closer to stoichiometry and have improved scintillation properties.

The invention provides novel biocompatible upconversion nanoparticle (UCNP) that comprises a core of cubic nanocrystals (e.g., comprising -Na Ln.sub.a, Ln.sub.b Ln.sub.c F.sub.4) and an epitaxial shell (e.g., formed from CaF.sub.2; wherein Ln.sub.b is Yb), and related methods of preparation and uses thereof.

The present invention relates to a method for producing luminescent nanoparticles wherein particle size of the nanoparticles is controlled. The method of the present invention includes admixing two or more rare earth metal salts in a first solvent and an organic oil to form a reaction mixture, and subjecting the reaction mixture to an inert gas so that flow rate of the inert gas is at least 2-5 L/h and pressure in the reaction vessel is at least 50 Pa over atmospheric pressure, preferably 50-80 Pa over atmospheric pressure.

The absorbance or emission wavelength of composite materials comprising a transition metal doped shell disposed over a rare earth doped core and a functionalizable group on the surface of the transition metal doped shell can change upon subjection to a carboxylic acid. This method of changing the absorbance or emission wavelength of a composite material can be used to identify counterfeit currency using an ink comprising a composite material.

An active laser medium for emitting a light beam by laser effect includes an XF2-doped crystal, wherein X is a chemical element from the alkaline-earth family and F is fluorine. The crystal is doped with trivalent ions including: a first category of optically active dopant ions, in which each dopant ion is an ion of a first rare earth; and a second category of optically inactive dopant ions, referred to as buffer ions, in which each dopant ion is an ion of a rare earth different from the first rare earth. The second category of dopant ions has at least ions of a second rare earth and ions of a third rare earth, different from one another. The invention provides an active laser medium that can be used to obtain both a desired emission spectrum shape and a high thermal conductivity.

Disclosed herein are embodiments of a composition comprising at least three layers. Layers one and two each either comprises a sensitizer or an emitter, typically a metal ion or a dye, and the third layer may or may not comprise a sensitizer or emitter. Upon exposure to light, such as infrared light, the composition produces visible and/or UV light. The composition may further comprise a capping moiety, a therapeutic agent, an uptake enhancer, a detection moiety that binds to a desired target, a quenching moiety, or a combination thereof. The composition may be a particle, such as a nanoparticle, or it may be a planar composition. Also disclosed are embodiments of a method for using the composition, including, but not limited to, a method for delivering a therapeutic agent, or a method for detecting a target, such as a biological target.