The present invention relates to a composition for the modulated release of
a biologically active agent. The composition comprises a biocompatible
polymeric matrix, a biologically active agent which is dispersed within
the polymeric matrix, and a metal cation component which is separately
dispersed within the polymeric matrix, whereby the metal cation component
modulates the release of the biologically active agent from the polymeric
matrix. The present invention also relates to a method for modulating the
release of a biologically active agent from a biocompatible polymeric
matrix, comprising the steps of dissolving a biocompatible polymer in a
solvent to form a polymer solution and also separately dispersing a metal
cation component and a biologically active agent within the polymer
solution. The polymer solution is then solidified to form a polymeric
matrix, wherein at least a significant portion of the metal cation
component is dispersed in the polymeric matrix separately from the
biologically active protein, and whereby the metal cation component
modulates the release of the biologically active agent from the polymeric
matrix.
