Sensor for luminescense-optical determination of an analyte
View Patent ↗The invention relates to an optochemical sensor functioning in accordance with the FRET-principle and exhibiting an acceptor (chromophore or luminophore) responsive to an analyte contained in a sample medium as well as a donor (luminophore), characterized in that acceptor and donor are located in separate chemical phases, whereby the phase containing the donor is essentially impermeable to the sample medium or to components of the sample medium affecting the luminescence characteristics of the luminophore. The invention further relates to a method for qualitative and/or quantitative determination of at least one analyte and/or component of a gaseous or liquid measuring medium according to the FRET-principle, characterized by the use of the sensor according to the invention.
1. An optical chemical sensor functioning in accordance with the FRET principle for detecting an analyte in a sample medium comprising:
a donor phase comprising a first luminophore and having an emission spectrum; and
an acceptor phase comprising a chromophore or a second luminophore responsive to the analyte and having an absorption spectrum, wherein
the donor phase is essentially impermeable to the sample medium or components of the medium capable of affecting the luminescence characteristics of the first luminophore,
there is at least partial overlap between the emission spectrum of the donor phase and the absorption spectrum of the acceptor phase, and
the acceptor phase is in sufficient spatial proximity to the donor phase for nonradiative energy transfer.
2. The sensor of claim 1 wherein the donor phase comprises a donor matrix material and the acceptor phase comprises an acceptor matrix material.
3. The sensor of claim 2 further comprising a mixture of the donor matrix material and the acceptor matrix material.
4. The sensor of claim 3 wherein the donor matrix material is homogenously distributed in the acceptor matrix material.
5. The sensor of claim 4 wherein the donor matrix material comprises particles having the first luminophore embedded therein.
6. The sensor of claim 3 further comprising a sensor layer comprising a thin layer of the mixture.
7. The sensor of claim 6 wherein the sensor layer is attached to a transparent substrate.
8. The sensor of claim 6 wherein the sensor layer is attached to a light guide.
9. The sensor of claim 6 further comprising an optical insulation layer permeable to the analyte and located between the sensor layer and the sample medium.
10. The sensor of claim 2 further comprising a sensor layer comprising a thin porous material wherein the pores of the material contain the donor matrix material and the acceptor matrix material.
11. The sensor of claim 10 wherein the sensor layer is attached to a transparent substrate.
12. The sensor of claim 10 wherein the sensor layer is attached to a light guide.
13. The sensor of claim 10 further comprising an optical insulation layer permeable to the analyte and located between the sensor layer and the sample medium.
14. The sensor of claim 5 wherein the chromophore or second luminophore of the acceptor phase is attached to the surface of the particles.
15. The sensor of claim 1 wherein the donor phase comprises at least one unplasticized polymer.
16. The sensor of claim 15 , wherein the at least one polymer comprises at least one of polyacryl nitrile, a derivative of polyacryl nitrile, PVC and polyvinylidene chloride.
17. The sensor of claim 1 wherein the acceptor phase comprises at least one of polyvinyl chloride, polystyrene, polycarbonate, polyethylene, polyurethane, silicone, copolymer of polyvinyl alcohol and polyvinyl acetate, cellulose, polyurethane with hydrophilic groups, polyhydroxyethylmethacrylate, crosslinked polyvinyl alcohol, and polyacrylamide.
18. The sensor of claim 17 wherein the acceptor phase further comprises up to 80% of a plasticizer.
19. A method for the qualitative and/or quantitative determination of an analyte in a sample medium comprising:
providing a sensor according to claim 1 ; and
contacting the sensor with a sample.
20. The method of claim 19 wherein the pH-value of the sample is determined.
21. The method of claim 19 wherein at least one of the concentration and activity of at least one ion in the sample is determined.
22. The method of claim 19 wherein the analyte is one or more components that exhibits acid or alkaline reactions in aqueous media while being gaseous under normal conditions.
23. The method of claim 21 wherein at least one of the concentration and activity of at least one of Li + , Na + , K + , Mg ++ , Ca ++ , or Cl − is determined.
24. The method of claim 21 wherein CO 2 or NH 3 is determined in a liquid medium.
25. The method of claim 19 wherein the sample is a body fluid.
26. The method of claim 19 wherein the sample is blood, plasma or serum.
27. The method of claim 19 wherein the sensor is used as a transducer.
28. The method of claim 19 wherein the sensor is an enzymatical sensor.