Detection and quantification of polymeric analytes using fluorescent lanthanide detection not relying on charge transfer from polymer aromatic groups
A method for determining samples including one or more organic polymers by mixing them with lanthanide(III) ions and detecting the signal of the lanthanide(III) ion chelated with the organic polymer.
1. A method for measuring concentration of one or more kinds of organic polymers in a sample, the method comprising:
admixing the sample and lanthanide(III) ion in the form of lanthanide salt, wherein the total concentration of the organic polymers in the sample is below 0.5 M and the concentration of the lanthanide(III) ion is ≤10 mM,
detecting a signal derived from the lanthanide(III) ion with a time-gated luminescence measurement, and
measuring a quantity of the one or more kinds of organic polymers in the sample based on the signal derived from the lanthanide(III) ion, wherein each kind of organic polymer comprises two or more groups capable of chelating with the lanthanide(III) ion and are selected from the group consisting of carboxylates, sulfonates, phosphates, phosphonates, carboxamides and amines, in proviso that the polymer is not a protein or an oligopeptide.
2. The method according to claim 1 , wherein the concentration of the lanthanide(III) ion is from 0.001 mM to 10 mM.
3. The method according to claim 1 , wherein the lanthanide(III) ion is admixed as lanthanide(III) halide.
4. The method according to claim 3 , wherein the lanthanide(III) halide is selected from europium(III) chloride and terbium(III) chloride.
5. The method according to claim 3 , wherein the lanthanide(III) halide is europium(III) chloride.
6. The method according to claim 1 , wherein at least one of the kinds of organic polymers does not comprise an aromatic group that is able to absorb excitation energy and transfer it essentially to the lanthanide(III) ion.
7. The method according to claim 1 , comprising introducing the sample through a pretreatment system prior to admixing with the lanthanide(III) ion.
8. The method according to claim 7 wherein the system is selected from dilution, filtration and size exclusion chromatography.
9. The method according to claim 1 , wherein each kind of organic polymer has a molecular weight >400 g/mol.
10. The method according to claim 1 , wherein the sample comprises two or more kinds of organic polymers and one of the organic polymers is quantified.
11. The method according to claim 1 , wherein the sample comprises two or more kinds of organic polymers and two or more of the organic polymers are quantified.
12. The method according to claim 1 , wherein the sample comprises two or more kinds of organic polymers and the total amount of the organic polymers are quantified.
13. The method according to claim 1 , wherein the lanthanide(III) ion is detected using two or more time-gated luminescence wavelengths.