Water-insoluble polysaccharide hydrogel foam for medical applications

A two-part aqueous based composition which upon mixing will yield a water-insoluble polysaccharide hydrogel foam, comprising

• (a) a first liquid component comprising
• (1) an aqueous dispersion of a water-insoluble di-or trivalent metal salt capable of reacting with an acid to form a water-soluble metal salt, said di- or trivalent metal ion capable of complexing with pendant carboxylate groups on water-soluble polysaccharides to form water-insoluble polysaccharide hydrogels, and
• (2) an effervescent compound capable of effervescence upon reaction with an acid;
• and
• (b) a second liquid component comprising an aqueous solution of a water-soluble acid;
• wherein either or both said first liquid component and said second liquid component further comprises a water soluble polysaccharide having pendant carboxylate groups dissolved therein

A method of making a medicated water-insoluble polysaccharide hydrogel foam comprising the steps of mixing together

• (a) a first liquid component comprising
• (1) an aqueous dispersion of a water-insoluble di-or trivalent metal salt capable of reacting with an acid to form a water-soluble metal salt, said di-or trivalent metal ion capable of complexing with pendant carboxylate groups on water-soluble polysaccharides to form water-insoluble polysaccharide hydrogels, and
• (2) an effervescent compound capable of effervescent compound capable of
• (b) a second liquid component comprising an aqueous solution of a biocompatible, water-soluble acid;
• wherein either or both said first liquid component and said second liquid component further comprises a water soluble polysaccharide having pendant carboxylate groups and a medicament dissolved or suspended therein.

A method of making a medicated water-insoluble polysaccharide hydrogel foam comprising the steps of mixing together

• (a) a first liquid component comprising:
• (1) water;
• (2) a water-soluble polysaccharide having pendant carboxylate groups;
• (3) a water-insoluble di- or trivalent metal salt capable of reacting with an acid to form a water-soluble metal salt, said di- or trivalent metal ion capable of complexing with pendent carboxylate groups on said polysaccharide to form a water-insoluble polysaccharide hydrogel;
• (4) an effervescent compound which effervesces upon reaction with an acid;
• and
• (5) a medicament and
• (b) a second liquid component comprising an aqueous solution of a biocompatible water-soluble acid.

A foamed polysaccharide hydrogel preoperative preparation made by the process comprising the steps of:

• (a) mixing together, to form a composite liquid mixture, a first liquid component comprising:
• (1) an aqueous dispersion of a water-insoluble di-or trivalent metal salt capable of reacting with an acid to form a water-soluble metal salt, said di- or trivalent metal ion capable of complexing with pendant carboxylate groups on water-soluble polysaccharides to form water-insoluble polysaccharide hydrogels, and
• (2) an effervescent compound capable of effervescence upon reaction with an acid;
• and a second liquid component comprising an aqueous solution of a biocompatible, water-soluble acid;
• wherein either said first or second liquid component further comprises a water soluble polysaccharide having pendant carboxylate groups and a medicament dissolved or suspended therein;
• (b) applying said composite liquid mixture to a surgical site;
• (c) allowing said composite liquid mixture to react to form a water-insoluble polysaccharide hydrogel foam.

A two-part aqueous based composition for preoperative preparations comprising

• (a) a first liquid component comprising:
• (1) water
• (2) a water-soluble polysaccharide having pendant carboxylate groups;
• (3) a water-insoluble di- or trivalent metal salt capable of reacting with an acid to form a water-soluble metal salt, said di- or trivalent metal ion capable of complexing with pendent carboxylate groups on said polysaccharide to form a water-insoluble polysaccharide hydrogel;
• (4) an effervescent compound which effervesces upon reaction with an acid;
• and
• (5) an antimicrobial;
• and
• (b) a second liquid component comprising an aqueous solution of a biocompatible water-soluble acid.

A foamed preoperative preparation comprising:

• (a) about 0.02 to 60 percent by weight of one or more polysaccharides complexed with a di- or trivalent metal salt;
• (b) the gaseous reaction product of an effervescent compound and a biocompatible, water-soluble acid in a concentration sufficient to provide the cured hydrogel foam with a density of from about 0.1 to 1 g/cm.sup.3 ;
• (c) about 0.001 to 10 percent by weight of an antimicrobial;
• and
• (d) from about 50 to 98 percent by weight water.

A device useful for forming a water-insoluble polysaccharide hydrogel foam comprising:

• (a) a first chamber containing a first liquid component comprising:
• (1) water;
• (2) a water-insoluble di- or trivalent metal salt capable of reacting with an acid to form a water-soluble metal salt, said di- or trivalent metal ion capable of complexing with pendant carboxylate groups on water-soluble polysaccharides to form water-insoluble polysaccharide hydrogels, and
• (3) an effervescent compound capable of effervescence upon reaction with an acid;
• and
• (b) a second chamber containing a second liquid component comprising an aqueous solution of a biocompatible, water-soluble acid;
• (c) means connected to said first and second chambers for allowing intermixing of said first liquid component and said second liquid component;
• (d) an outlet in said device capable of allowing discharge of the mixture of said first liquid component and said second liquid component;
• wherein either or both said first liquid component and said second liquid component further comprises a water-soluble polysaccharide having pendant carboxylate groups and a medicament dissolved or suspended therein;