Diester crosslinked polyglucan hydrogels and reticulated sponges thereof
AssigneeInternational Paper Company
InventorsJames H. Manning, John H. Stark
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AssigneeInternational Paper Company
InventorsJames H. Manning, John H. Stark
Estimating the term…
Novel hydrogel compositions of diester crosslinked polyglucans and a process for their preparation are provided. Amylose, dextran, and pullulan succinates and glutarates when crosslinked as described were found to not only have use as general fluid sorbants but also to have exceptional hemostatic activity, adherence to a wound, and bioabsorption without causing undue irritation of the tissue or toxic effects. Reticulated hydrogel sponges made of the crosslinked diesters which are particularly useful as general fluid sorbants, and those of amylose succinate and amylose glutarate are most excellent bioabsorbable hemostatic agents. The sponges are made by lyophilizing water-soluble salts of the mono- or half-esters, such as water-soluble salts of amylose succinate or amylose glutarate, under process conditions of the invention in the presence of a reticulating agent which causes a controlled melting of the salt solution as it nears the dry state during the lyophilizing step. The resulting reticulated, porous, open-celled sponge is then crosslinked by heating the sponge under dehydrating conditions to form diester-crosslinks. The sponge is highly porous, is moderately strong, and has the ability to retain up to 40 times its weight of isotonic saline. When neutralized with physiologically acceptable salts, the sponge has exceptional hemostatic activity, adherence to bleeding tissue, and bioabsorption without causing substantial irritation of the tissue or toxic effects. The invention also comprises a process of providing hemostasis at the site of a wound, employing the diester cross-linked polyglucan hydrogels or reticulated sponges thereof.
A hydrogel solid comprising diester crosslinked polyglucan selected from the class consisting of amylose, dextran and pullulan succinates and glutarates, said hydrogel solid being water-insoluble and the neutral pH sodium salt of which has a saline retention of isotonic saline solution sufficient to increase the weight of said hydrogel solid to an amount of between about 5 and 90 times its weight.
A reticulated, porous sponge of diester crosslinked amylose hydrogel selected from the class consisting of succinate and glutarate, said hydrogel being water-insoluble, the neutral pH sodium salt of which has a saline retention of isotonic saline solution sufficient to increase the weight of said hydrogel to an amount of between about 5 and 40 times its weight, having an average pore size of less than about 1 millimeter and a void volume of between about 80% and 95%, having the ability to retain up to 40 times its weight of isotonic saline.
Dependencies are inferred from the claim text.