Appeal No. 2000-0320 Page 9
Application No. 08/480,082
Useful counter-ions in Viegas' invention are cationic
gelling agents, preferably, comprising a divalent or trivalent
cation. Useful divalent cations include the alkaline earth
metals, preferably, selected from the group consisting of
calcium and strontium. Useful trivalent cations include
aluminum. The most preferred counter-ions are contained in
ionic compounds selected from pharmaceutically-acceptable
gluconates, fluorides, citrates, phosphates, tartrates,
sulfates, acetates, borates, chlorides, and the like having
alkaline earth metal cations such as calcium and strontium.
Especially preferred counter-ion containing inorganic salts
for use as ionic polysaccharide gelling agents include such
inorganic salts as the chloride salts, such as strontium
chloride, calcium chloride, and mixtures thereof.
Thompson discloses temporary medical devices such as
stent implants which can be disintegrated in-vivo upon demand
by release of an agent held trapped within the device. The
device is fabricated from a matrix polymer material which is
essentially insoluble in body fluids and a disintegration
agent which acts to initiate decomposition of the matrix
Page: Previous 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Next
Last modified: November 3, 2007