The present application discloses novel lanthanide chelate designs (Formula (I) and Formula (III)) having fluorenyl-, fluorenylethynyl, 9H-carbazolyl-, 9H-carbozolylethynyl-, dibenzothiophenyl-, dibenzothiophenylethynyl-, dibenzofuranyl or dibenzofuranylethynyl pyridine chromophores around an emitting lanthanide ion, e.g. an europium(III) ion. The three-membered ring chromophores exhibit high molar absorptivity and luminescence with lanthanide ions. The application also discloses a detectable molecule comprising a biospecific binding reactant useful in bioaffinity based binding assay, luminescent lanthanide chelating ligands, as well as a solid support conjugated with the chelates. ##STR00001##

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.

Provided herein are lanthanide complexes that exhibit specific subcellular localization to primary cilium. The lanthanide complexes provided herein are useful for imaging, tagging, and pull down of binding targets located in primary cilium.

The invention relates to novel luminescent compositions of matter containing two fluorophores (sensitizers), synthetic methods for making the compositions, macromolecular conjugates of the compositions, and the use of the compositions and their conjugates in various methods of detection. The invention also provides kits containing the compositions and their conjugates for use in the methods of detection.

The present invention relates to a water-soluble, simple, stable tris(N-(tert-butyl)acetamide) cyclen-based europium complex HGEu001 which exhibits the specific subcellular localization in the primary cilium with a quantum yield as high as 10% in water and a lifetime of 0.56 ms lifetime. In particular, the present invention provides simplicity of the design and synthesis of a complex. Comprehensive studies were performed in numerous cell lines, such as HeLa, SN-K-SH and MRC5; the motif structure, HGEu002, has also been synthesized as the negative control for in vitro imaging studies. The two photon in vitro imaging were done in three dimensions to emphasize on the specific localization in primary cilium of HGEu001. This is one of the very limited examples for direct primary cilium imaging.

The invention relates to complexing agents of formula (I)

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in which A.sub.1, A.sub.2, A.sub.3 and R.sub.1 are as defined in the description. The invention also relates to lanthanide complexes obtained from said complexing agents.

The invention can be used for marking biological molecules.

Disclosed is information related to determining Escherichia coli from a sample such as urine. According to the method, part of sample is admixed with a reagent including a lanthanide(III) ion, a transition metal ion, and a transition metal ion/E. coli-specific M13 phage, and another part of the sample is admixed with the reagent including lanthanide(III) ion, the transition metal ion a wild-type M13 phage. The signals derived from the lanthanide(III) ions in the admixtures were detected with time-gated luminescence measurement. The presence of E. coli in the sample was determined by comparing the lanthanide(III) ion signal in the presence transition metal ion/E. coli-specific M13 phage and the wild type M13 phage.

Disclosed are methods of measuring enzyme activity in a sample. The methods use disulfide-containing detection reagents with an electrochemiluminescent functional group.

The present invention is related to a method for determining mucosa alterations in a subject, in particular to a method for determining mucosa alterations in a sample using a reagent comprising a lanthanide(III) ion, and an array of indicator molecules configured to interact with the sample. The reagent comprising the lanthanide(III) ion does not have any sample or indicator molecule specific recognition elements. The invention relates also to an array for determining mucosa alterations, the array comprising one or more indicator molecules configured to interact specifically with the sample and a reagent comprising a lanthanide(III) ion. The reagent comprising a lanthanide(III) does not have any sample or indicator molecule specific recognition elements.

Disclosed is a method for enhancing the optical signal of precious metal nanoparticles by introducing linker molecules for precious metal nanoparticles to form clusters in a stable colloidal suspension. The formation of clusters according to the present disclosure not only enhances the optical signal, but also can alter the optical spectrum, providing an alternative color for use in visual-based bioassays such as lateral flow immunoassays against the white test paper strips. The formed clusters are capable of passive adsorption of a variety of biomolecules which effectively bind onto the surface, requiring a minimum modification in the bio-assay protocol from that use for standard gold nanoparticles, which is being widely-used in lateral flow immunoassays.