Abstract: This invention concerns a non-radioactive homogenous proximity assay for cellular transport system. The assay format disclosed here takes advantageous of the fact that ABC transporters have two similar ATP binding sites, and thus allowing two ATP molecules to bind simultaneously to these adjacent sites.

Abstract: The invention relates to an enhancement solution for an assay technology using lanthanide ions or their chelates as labels and dissociative fluorescence enhancement as a tool for detection, wherein said enhancement solution comprises a ?-diketone of formula I wherein R1 is an aryl, optionally mono- or multi-substituted, and R2 is a straight or branched alkyl chain with 2 to 9 carbon atoms substituted with four or more fluorine atoms. The invention further relates to a bioaffinity assay using lanthanide ions or their chelates as labels and dissociative fluorescence enhancement as a tool for detection comprising the use of said enhancement solution.

Abstract: The invention relates to an enhancement solution for an assay technology using lanthanide ions or their chelates as labels and dissociative fluorescence enhancement as a tool for detection, wherein said enhancement solution comprises a ?-diketone of formula I wherein R1 is an aryl, optionally mono- or multi-substituted, and R2 is a straight or branched alkyl chain with 2 to 9 carbon atoms substituted with four or more fluorine atoms. The invention further relates to a bioaffinity assay using lanthanide ions or their chelates as labels and dissociative fluorescence enhancement as a tool for detection comprising the use of said enhancement solution.

Abstract: The invention relates to an enhancement solution for an assay technology using lanthanide ions or their chelates as labels and dissociative fluorescence enhancement as a tool for detection, wherein said enhancement solution comprises a &bgr;-dietone of formula I 1

Abstract: Bifuncitonal chelating pyridine compound and its use for conferring chelating properties on organic compounds. The pyridine compound has the structure ##STR1## where (i) n is an integer 1 or 2,(ii) R.sub.1, R.sub.2 and R.sub.3 represent groups that have no electrons capable of significantly delocalizing or resonating with the pyridine ring, such as hydrogen, alkyl or aralkyl having an aliphatic carbon atom next to the pyridine ring; at least two of R.sub.1, R.sub.2 and R.sub.

Abstract: The invention is a luminescence energy transfer based bioaffinity assay comprising a first group labeled with an energy donating compound (donor) and a second group labeled with an energy accepting compound (acceptor), wherein the donor is a luminescent lanthanide chelate having a long excited state lifetime and the acceptor is either a luminescent compound having a short excited state lifetime or a nonluminescent compound. The increase or decrease, respectively, in the energy transfer from the donor to the acceptor resulting from shortening or lengthening, respectively, of the distance between the said groups, is measured. Characteristic for the invention is that the lanthanide energy emission and the acceptor energy absorption do not essentially or not at all overlap each other.

Abstract: Method for a homogeneous biospecific affinity assay for determining the content of a substance (analyte) in a biological sample. The assay is carried out in an aqueous reaction medium by means of time-resolved fluorescence spectroscopy and with a biospecific affinity reactant labeled with a lanthanide chelate in which a lanthanide ion exhibiting ionic fluorescence is chelated by a ligand bound covalently to the reactant. The characteristic feature is(i) that the lanthanide chelate formed by the lanthanide ion together with the covalently bound ligand forms a fluorescent chelate, and(ii) that a modulator is added which stabilizes the lanthanide chelate so that the lanthanide fluorescence as measured from the medium becomes a practically pure function of the analyte concentration therein.

Abstract: A method of conducting assays for analytes, usually from biological samples, utilizing bioaffinity reagents linked to luminescent lanthanide chelates, which are synthesized so that the non-radiative quenching of the ion luminescence through C--H bond vibrational energy manifolds is avoided using a stable chelate where the CH and CH.sub.2 groups in the vicinity of the emittive ion are substituted with CD and CD.sub.2 groups hence producing improved luminescence quantum yield and higher assay sensitivities.

Abstract: The method for demonstrating the presence of an activity of an enzyme by(a) incubating said enzyme with a fluorogenic substrate A which is converted by the enzyme to a product B differing from A in respect to its fluorescent properties, A and/or B carrying a chromophore which is a triplet sensitizer having a triplet energy level above the excitation energy level of a lanthanide ion selected from the group consisting of Eu.sup.3+, Tb.sup.3+, Dy.sup.3+ and Sm.sup.3+ and which is capable of chelating said lanthanide ion by means of an oxygen or nitrogen atom in said chromophore, and that B differs from A either by(i) carrying a different chromophore, or(ii) having a different chelating ability, and(b) measuring the change in fluorescence caused by said enzyme.

Abstract: Compound having the following structure: ##STR1## R is a direct chain or branched alkylene group comprising 2-8 carbon atoms,n and m are 0 or 1,Y is a carboxylic or phosphonic acid, andX is an active functional group which permits covalent coupling to a bio-organic molecule.

Abstract: Method for quantitative determination of a biospecific affinity reaction in which an immunochemical compound labelled with a lanthanide chelate is used which can be detected by means of time-resolved fluorescence in which the amount of labelled compound present in the biospecific affinity reaction can be measured without the separation of free and biospecifically bound labelled compound having to be carried out.

Abstract: Method for fluorescence spectroscopic determination of a biological substance provided with a marker consisting of a lanthanide chelate complex formed by a lanthanide coupled to the substance via a chelate forming compound, such as an EDTA-analogue, the lanthanide ion before the detection is dissociated from the active substance for instance by adding a buffer with a pH value below 3.5 and a splitting detergent, whereafter the excitation in the determination takes place in the solution in the presence of a .beta.-diketone by using a short radiation pulse and the fluorescence from the marker is detected when the fluorescence from the noise sources has substantially ceased.

Abstract: An improved method of determining the nature of a substance by fluoroscence spectroscopy wherein a fluorescent marker is coupled to the molecules of the substance comprises the use of a marker having a longer period of fluorescence than those of possible sources of noise and by employing an exciting radiation pulse of short duration so that the fluorescence of the marker is detected after the objectionable sources of fluorescence have ceased; the marker including a fluorescent lanthanide chelate complex.