Organic compounds

Abstract

A polylactide in a purified state, which meets the requirements of the colour strengths of reference solutions B 2 -B 9 of the brown colour test of the European Pharmacopoeia, 2nd Edition (1980) part I, Section V, 6.2 and containing one or more metals in cationic form, the metal ion(s) having a concentration of at most 10 ppm. The polylactide is especially suitable for use as microparticles or implants, and contains preferably a hydrophilic drug, like octreotide or a lipophilic drug like bromocriptine.

1 - 31 . (canceled)  
     
     
         32 . A polymer, which is off-white to white in color, and which polymer contains one or more metals in cationic form, the metal cation(s) having a concentration of at most 10 ppm, wherein the polymer is obtained through the process of purification comprising the steps of 
 contacting a solution of an impure polymer with a matrix, and    isolating the purified polymer from the solution.    
     
     
         33 . A polymer, according to  claim 32 , wherein its off-white to white color is further defined by the requirements of the colour strengths of reference solutions B 2 -B 9  of the brown colour test of the European Pharmacopeia, 2 nd  Edition (1980) part 1, Section V, 6.2.  
     
     
         34 . A polymer according to  claim 33  wherein the purified polymer is a polylactide polymer.  
     
     
         35 . A polymer according to  claim 34  wherein the polylactide polymer is a polylactide co-glycolide polymer.  
     
     
         36 . A polymer according to  claim 35  wherein the polylactide co-glycolide polymer contains Sn++ ions as the cationic metal ion(s).  
     
     
         37 . A polymer according to  claim 36  wherein the polylactide co-glycolide polymer contains the Sn++ in a concentration of from about 1. To about 1.5 parts per million (ppm).  
     
     
         38 . A polymer according to  claim 32  wherein said metal ion has ethyl hexanoate as a corresponding salt anion.  
     
     
         39 . A polymer according to  claim 37  wherein the polylactide co-glycolide polymer is a polylactide co-glycolide having a mean molecular weight (Mw) of from 25,000 to 100,000 and a polydispersity (Mw/ Mn ) of from 1.2 to 3.0.  
     
     
         40 . A polymer according to  claim 35  wherein the polylactide co-glycolide polymer is linear.  
     
     
         41 . A polymer according to  claim 40  wherein the linear polylactide co-glycolide polymer has a lactidal glycolide molar ratio of 100-25/0-75.  
     
     
         42 . A polymer according to  claim 40  wherein the linear polylactide co-glycolide polymer has a lactidal glycolide molar ratio of 75-25/25-75.  
     
     
         43 . A polymer according to  claim 40  wherein the linear polylactide co-glycolide polymer has a lactidal glycolide molar ratio of 60-40/40-60.  
     
     
         44 . A polymer according to  claim 35  wherein the polylactide co-glycolide polymer is star-shaped.  
     
     
         45 . A polymer according to  claim 44  wherein the star-shaped polylactide co-glycolide polymer is an ester of a polyol containing at least 3 hydroxyl groups.  
     
     
         46 . A polymer obtained through the process according to  claim 32 , wherein said matrix has surface acidic groups.  
     
     
         47 . A polymer obtained through the process according to  claim 32 , wherein said matrix has surface carboxylic groups.  
     
     
         48 . A polymer obtained through the process according to  claim 32 , further including, contacting the solution of impure polymer with activated charcoal.  
     
     
         49 . A polymer obtained through the process according to  claim 32 , wherein the matrix is activated charcoal.  
     
     
         50 . A polymer obtained through the process according to  claim 32 , further including the step of ultrafiltration.  
     
     
         51 . A polymer obtained through the process according to  claim 32 , wherein the polymer is dissolved in acetone.