Fluorescent isothiocyanate (fitc) sinistrin, its production and use
The invention concerns fluorescein isothiocyanate-sinistrin (FITC-sinistrin), a method for its production, its use as a marker substance in a diagnostic agent and a corresponding diagnostic agent.
1. A method for producing fluorescein isothiocyanate-sinistrin (FITC-sinistrin) comprising:
(a) reacting sinistrin with sodium hydride in a solvent to form a reaction mixture;
(b) adding FITC to the reaction mixture; and
(c) isolating FITC-sinistrin as a solid.
2. The method of claim 1 wherein the solvent is anhydrous dimethylformamide.
3. The method of claim 1 wherein the FITC-sinistrin is isolated by adding an aqueous ammonium chloride solution to the reaction mixture, extracting the FITC-sinistrin with diethyl ether and removing the diethyl ether to isolate solid FITC-sinistrin.
4. The method of claim 3 wherein the solid FITC is purified by at least one of recrystallization and gel filtration.
5. Fluorescein isothiocyanate-sinistrin (FITC-sinistrin) obtainable by the method of claim 1 .
6. A composition comprising fluorescein isothiocyanate-sinistrin (FITC-sinistrin) in a physiologically acceptable solution.
7. The composition of claim 6 wherein the solution comprises FITC-sinistrin in a concentration of 25–125 mg/ml.
8. A method for measuring renal function in a patient comprising:
administering to the patient a FITC-sinistrin;
beaming light onto the skin of the patient; and
detecting the fluorescent light emitted from the skin wherein the amount of fluorescence is related to the renal function of the patient.
9. The method of claim 8 wherein the FITC-sinistrin is prepared by the method of claim 9 .
10. The method of claim 8 wherein the FITC-sinistrin is administered in a dose of 5–50 mg/kg.