Artificial Vitreous Humor for the Investigation of Drugs and Drug Formulations

Abstract

The invention relates to an artificial vitreous humor composition comprising a phosphate buffer, wherein the phosphate buffer has a pH value in the range from 7.0 to 7.7, particularly from 7.1 to 7.6, more particularly from 7.2 to 7.5. The invention further relates to a method of production of an artificial vitreous humor composition, a method for analyzing the behavior of a substance, a method for analyzing the change of the artificial vitreous humor composition upon contact with a substance and a kit of parts.

1 . An artificial vitreous humor composition comprising a phosphate buffer, wherein the phosphate buffer has a pH value in the range from 7.0 to 7.7. 
     
     
         2 . The artificial vitreous humor composition of  claim 1 , wherein the phosphate buffer is phosphate buffer saline (PBS) in the range from 0.001 to 0.2 M. 
     
     
         3 . The artificial vitreous humor composition of  claim 1 , wherein the composition comprises at least one of up to 578 μM creatinine, up to 28.1 mM glucose, up to 58.5 mM urea, 200 to 1630 μM xanthine, 100 to 800 μM hypoxanthine, 0.1 to 23 mM sodium lactate, and 50 to 300 μM glutathione. 
     
     
         4 . The artificial vitreous humor composition of  claim 1 , wherein the composition comprises 64.6 μM creatinine, 2.2 mM glucose, 7.6 mM urea, 580 μM xanthine, 309 μM hypoxanthine, 10.5 mM sodium lactate and 200 μM glutathione. 
     
     
         5 . The artificial vitreous humor composition of  claim 1 , wherein the composition comprises 20 to 300 mg/L type II collagen. 
     
     
         6 . The artificial vitreous humor composition of  claim 1 , wherein the composition does not comprise ascorbic acid. 
     
     
         7 . A method for the production of an artificial vitreous humor composition, comprising the steps
 (i) Providing stock solutions of glucose, creatinine, sodium lactate, glutathione and urea in water, of hypoxanthine in formic acid:water of 2:1 ratio, and of xanthine sodium in 1M NaOH;   (ii) Mixing of stock solutions of step (i) in a phosphate buffer with a pH value in the range from 7.0 to 7.7, and pH adjustment to the pH value of the phosphate buffer;   (iii) Addition of hyaluronic acid to the mixture obtained in step (iii) and stirring at 2 to 8° C. at least for 4 hours;   (iv) Addition of collagen type-II to the mixture obtained in step (iii);   (v) Optionally sterile-filtering of the mixture obtained in step (iv).   
     
     
         8 . A method for analyzing the behavior of a substance comprising the steps
 (i) providing an artificial vitreous humor composition of  claim 1  in an in-vitro environment;
 (ii) applying the substance to the artificial vitreous humor; and 
 (iii) determining at least one property of the applied substance. 
   
     
     
         9 . The method of  claim 8 , wherein the substance to be applied is at least one of a macromolecule, a drug formulation, an excipient, a protein or a combination thereof. 
     
     
         10 . The method of  claim 8 , wherein the substance to be applied comprises molecules having a size in a range between 100 Da and 1800 kDa. 
     
     
         11 . The method of  claim 8 , wherein the at least one property of the applied substance is selected from the group consisting of stability, bioavailability, release from DDS system and degradation of DDS system. 
     
     
         12 . The method of  claim 8 , wherein the applied substance is left in the artificial vitreous humor composition for up to 360 days, prior to step (iii). 
     
     
         13 . A method for analyzing the behavior of an artificial humor composition comprising the steps
 (i) providing an artificial vitreous humor composition of  claim 1  in an in-vitro environment;
 (ii) applying a substance to the artificial vitreous humor; and 
 (iii) determining at least one property of the artificial humor composition. 
   
     
     
         14 . An artificial vitreous humor composition produced by the method of  claim 7 . 
     
     
         15 . A kit of parts for the production of an artificial vitreous humor composition, comprising
 (A) a phosphate buffer, having a pH value in the range from 7.0 to 7.7;   (B) at least one selected from the group consisting of creatinine, glucose, urea, xanthine, hypoxanthine, sodium lactate, glutathione;   (C) type II collagen and/or sodium hyaluronate; and optionally   (D) instructions for use.   
     
     
         16 . (canceled) 
     
     
         17 . Use of a phosphate buffer saline having a pH value in the range from 7.0 to 7.7 for the production of an artificial vitreous humor composition according to  claim 1 . 
     
     
         18 . (canceled)