Abstract: The present invention provides a method for determining concentration of polyelectrolyte or phosphonate in a sample comprising polyelectrolyte or phosphonate in low concentrations. The method comprises admixing the sample with a reagent comprising a lanthanid(lll) ion; admixing the sample with silica; allowing the polyelectrolyte or phosphonate in the sample to interact with the reagent comprising the lanthanide(lll) ion and the silica; exciting the sample and detecting a sample signal deriving from the lanthanide(lll) ion by time-resolved fluorescence measurement; and determining the concentration of the polyelectrolyte or phosphonate in the sample by using the detected sample signal.

Abstract: The present invention provides a method for determining concentration of polyelectrolyte or phosphonate in a sample comprising polyelectrolyte or phosphonate in low concentrations. The method comprises admixing the sample with a reagent comprising a lanthanid(lll) ion; admixing the sample with silica; allowing the polyelectrolyte or phosphonate in the sample to interact with the reagent comprising the lanthanide(lll) ion and the silica; exciting the sample and detecting a sample signal deriving from the lanthanide(lll) ion by time-resolved fluorescence measurement; and determining the concentration of the polyelectrolyte or phosphonate in the sample by using the detected sample signal.

Abstract: The present invention relates to utilization of lanthanide time resolved fluorescence for determining concentration of trivalent metal ions in a sample. In the method sample comprising trivalent metal ions is admixed with a reagent comprising a lanthanide (lll) ion and a chelating agent. The trivalent metal ion in the sample is allowed to interact with the reagent comprising the lanthanide (lll) ion and the chelating agent, followed by exciting the sample and detecting a signal deriving from the lanthanide (lll) ion, and determining the concentration of the trivalent metal ion in the sample by using the detected signal.

Abstract: The present invention relates to a method for determining hydrolysis degree and charge density of polyelectrolyte or phosphonate in a sample. In the method the sample is mixed with a reagent comprising a lanthanide(lll) ion. The mixture is excited at an excitation wavelength and a signal deriving from the lanthanide(lll) ion is detected by using time-resolved fluorescence measurement, followed by determining the hydrolysis degree and the charge density of the polyelectrolyte or phosphonate by using the detected sample signal.

Abstract: The present invention relates to a method for determining concentration of phosphate in a sample method comprises mixing the sample with a lanthanide (III) chelate or with lanthanide (III) ion and a chelation agent; allowing the phosphate in the sample to interact with the lanthanide (III) chelate; or with the lanthanide (III) ion and the chelation agent; exciting the sample and detecting a sample signal deriving from the sample by using time-resolved luminescence measurement; and determining the concentration of the phosphate in the sample.

Abstract: The present invention relates to utilization of lanthanide time resolved fluorescence for determining total concentration of polyelectrolyte or phosphonate in a sample. In the method sample comprising two or more polyelectrolytes and/or phosphonates is acidified followed by admixing the acidified sample with a reagent comprising a lanthanide(lll) ion. The polyelectrolyte or phosphonate in the sample are allowed to interact with the reagent comprising the lanthanide(lll) ion, followed by exciting the sample and detecting a signal deriving from the lanthanide(lll) ion, and determining the concentration of the polyelectrolyte or phosphonate in the sample by using the detected signal.