Biodegradable polymeric film

Abstract

This invention provides biodegradable, biocompatible polymeric films having uniform selected thicknesses between about 60 micrometers and about 5 mm useful in the manufacture of therapeutic implants for insertion into a patient's body and methods of making them. The films may be shaped to cover implants made of other materials to improve their biocompatibility. The films may be coated with or incorporate bioactive agents. They may have differing properties, e.g., porosity, thickness, and degradation rate, in different areas.

1 . A biodegradable, biocompatible polymeric film made of a polymer having a molecular weight of between about 5 kD and about 600 kD, having a uniform thickness between about 60 micrometers and about 1 mm, and being capable of completely degrading in vivo in a human body in no more than about four months, said polymeric film further comprising a bioactive agent.  
     
     
         2 . The biodegradable polymeric film of  claim 1  wherein said bioactive agent is a cell-attachment enhancer coated thereon.  
     
     
         3 . The biodegradable polymeric film of  claim 1  wherein said bioactive agent is a growth factor.  
     
     
         4 . A therapeutic device comprising an implant which is at least partially covered with a biodegradable, biocompatible polymeric film which has a uniform selected thickness between about 60 micrometers and about 5 mm., and a contoured surface, and said film is capable of completely degrading in vivo in no more than four months.  
     
     
         5 . A method of making a biocompatible, biodegradable polymeric film having a selected thickness between about 60 micrometers and about 5 mm and having a selected degradation time in vivo comprising: 
 a) selecting a polymeric material having degradation characteristics providing said selected degradation time;    b) solubilizing said polymeric material in a suitable solvent;    c) removing dissolved gases from said solution;    d) pouring a sufficient amount of said solution onto a substantially non-stick surface to form a film of the selected thickness;    e) drying said solution of step d) to form a film;    f) removing substantially all residual solvent from said film, whereby a biocompatible, biodegradable polymeric film having said selected thickness and degradation time is produced.    
     
     
         6 . The method of  claim 5  also comprising forming holes in the film of step (f) whereby said film is permeable to liquid-borne nutrients but not to cells.  
     
     
         7 . The method of  claim 5  comprising softening the film of step (f) with a biocompatible solvent in combination with a co-solvent.  
     
     
         8 . The method of  claim 5  also comprising coating said film with a bioactive agent.