The present invention relates to improved methods for making and using
bioadhesive, bioresorbable, anti-adhesion compositions made of inter-
macromolecular complexes of carboxyl-containing polysaccharides, polyethers, polyacids, polyalkylene oxides, multivalent cations and / or polycations. The polymers are associated with each other and are then either dried into membranes or sponges or are used as fluids or microspheres. Bioresorbable,
bioadhesive, antiadhesion compositions are useful in
surgery to prevent the formation and reformation of post-
surgical adhesions. The compositions are designed to breakdown
in vivo, and thus be removed from the body. Membranes are inserted during
surgery either dry or optionally after conditioning in aqueous solutions. The antiadhesion,
bioadhesive, bioresorptive, antithrombogenic and physical properties of such membranes and gels can be varied as needed by carefully adjusting the pH and / or cation content of the
polymer casting solutions, polyacid composition, the polyalkylene
oxide composition, or by conditioning the membranes prior to surgical use. Multi-layered membranes can be made and used to provide further control over the physical and biological properties of antiadhesion membranes. Membranes and gels can be used concurrently. Antiadhesion compositions may also be used to lubricate tissues and / or
medical instruments, and / or deliver drugs to the
surgical site and release them locally.