JP2644626B2 - Method for producing polysaccharide foam - Google Patents

Description

DETAILED DESCRIPTION The present invention relates to a process for producing polysaccharide foams, particularly alginates, chitosan, starch, and hyaluronate foams. The present invention also includes polysaccharide foam materials and wound dressings, effervescent cell replica culture substrates, anti-tissue barrier substrates, or other absorbent materials comprising such foams produced by the methods of the present invention. It is also a thing.

Alginates, especially calcium alginate and calcium alginate derivatives, have long been used to make fibers and yarns that are knitted into woven or nonwoven fabrics, primarily for use as swabs and bandages for medical and surgical purposes. Was known to be useful.

For example, GB 1283399 describes and claims a method for preparing a soluble calcium-containing alginate material. Such soluble calcium-containing alginate materials are obtained by acidifying calcium alginate with a calculated amount of an acid sufficient to remove the desired amount of calcium and selecting the acidified calcium alginate salt from ammonia, amines, substituted amines. It consists of reacting the base in excess and washing the soluble calcium-containing alginate to remove excess base.

A variety of gauze is made from this material, and the gauze can be further processed as described herein.

British Patent No. 1394742 relates to a surgical bandage, which consists of a woven gauze layer adhered to a fiber backing layer, which gauze is made of alginate material and has less flexibility and stretch than the gauze itself. Has the property.

GB 1570485 relates to an absorbent material for aqueous solutions consisting of an open-cell foam having a hydrophilic gel with unique properties in the cells. Alginate is mentioned as a typical hydrophilic gel. The specification states that the incorporation of these substances into a reticulated foam results in the gel being contained within the foam of the firm and providing such an absorbent material.

U.S. Pat.No. 4,421,583 relates to nonwoven alginate fabrics useful as wound dressings, such wound dressings spreading calcium alginate filament tow into running water and interlacing the spread filaments with each other. By overfeeding on a water permeable support and bonding the filaments together at interlaced contact points by drying. The filaments used are preferably predrawn in a steam environment, washed with water and dried or optionally dried subsequently by suction on a water-permeable support.

U.S. Pat. No. 4,793,337 discloses an improved adhesive structure for adherence of a product to a wound from which exudate has escaped. The structure has an absorbent area of absorbent fibrous fabric or firm material located intermediate the first and second contact areas, thereby providing an area between the first and second areas in case of severe exudate outflow. And increased adhesion between the second area and the product is provided. The description states, in combination with calcium powder for the absorbent substance,
The use of calcium alginate is also disclosed.

U.S. Pat. No. 4,984,575 discloses a dimensionally stable alginate hydrogel foam wound dressing that absorbs wound exudate without appreciable swelling. The wound dressing contains an alkaline earth metal (except for magnesium) salt and a group III metal salt of alginic acid. The hydrogel foam comprises a first liquid component comprising (a) a water-insoluble suspension of water-insoluble particles of a divalent or trivalent metal salt and (b) a foaming compound which reacts with the acid to foam. An aqueous solution of a compatible water-soluble acid, wherein at least one component dissolved therein can be formed by mixing together a second liquid component comprising a water-soluble alginate. Upon mixing, the water-insoluble metal salt reacts with the water-soluble acid to form a water-soluble metal salt, which is ionized. Polyvalent cations that cause the formation and precipitation of a water-insoluble alginate hydrogel are released from the water-soluble metal salt complex together with the carboxylic acid groups of the water-soluble alginic acid. At the same time, the effervescent compound reacts with the water-soluble acid, resulting in the evolution of gas, which leads to the formation of a stable hydrogel foam.

Commercially available alginate products are marketed, inter alia, as wound hemostatic dressings using nonwoven fiber technology.
However, while non-woven alginate materials have satisfactory performance, they are difficult to handle. Several attempts have been made to improve handling. For example,
Swedish Patent Application No. 424956 describes an alginate hydrogel wound dressing that can be formed on a wound in combination with an elastic rubber-like composition. In another attempt to provide a more readily usable material, U.S. Pat.
No. 903 proposes the use of freeze-dried foam. The disadvantages of all these prior arts with respect to the foam production process are that the pore size of the foam is little or not controllable and the product is relatively difficult to handle.

Thus, in accordance with the teachings of the present invention, there is provided a method of forming a polysaccharide foam comprising the steps of preparing an aqueous solution containing a water-soluble polysaccharide and then mechanically foaming the solution.

To make a polysaccharide foam, the foam can be produced by beating the material or otherwise by mechanical stirring. Mechanical foaming introduces gas into the solution,
Then, the method includes a step of shearing the solution in order to derive the effect of mixing in which gas bubbles in the solution are diffused very finely. In the initial step of mechanical foaming, when the total amount of gas entering the solution is small, the gas bubbles are spherical. As the total amount of gas entering the solution rises, the gas bubbles change from spherical to polyhedral. The solution disperses in the thin membrane between adjacent gas bubbles and in the ribs and spokes where the gas bubbles are in close proximity. The result is a foamed polymer having gas dispersed throughout the solution in the cellular structure. In the present invention, the determination of the relative intensity and / or duration of mechanical stirring to control the pore size of the foam is generally conceivable to those skilled in the art. The pore size of the foam is controlled in the range of 5-500μ, preferably 50-500μ.

Examples of the soluble polysaccharide include alginic acid and hyaluronic acid. Specifically, the soluble polysaccharide is a soluble polysaccharide salt, such as alginate or hyaluronate,
In particular, sodium alginate and sodium hyaluronate can be used. Alternatively, as the soluble polysaccharide, one or more of carrageenan, chitosan, starch, or amylose or amylopectin can be used.
It will be readily appreciated by those skilled in the art that chitosan is soluble in acids but not in neutral or basic solutions, while starch is soluble in base solutions. Thus, when chitosan is used according to the present invention, the mechanical foaming step is performed in an aqueous acidic solution. When starch is used, the foaming step is performed in a basic aqueous solution.

According to one aspect of the invention, a blowing agent can be included in the aqueous solution as an aid to foam the aqueous solution. Examples of the foaming agent include surfactants, particularly ionic or nonionic surfactants. Examples of the ionic surfactant include sodium stearate, sodium dodecyl sulfate, α-olefin sulfonate (commercially available as “Siponate 301-10”), sulfoalkylamide, monocarboxy coco imidazoline compound, dicarboxy It can be selected from coco imidazoline compounds and sulfated aliphatic polyoxyethylene quaternary nitrogen compounds.

The nonionic surfactant can be selected from, for example, octylphenol ethoxylate (available from Rom & Hass Co. under the trade name "Triton X-100"), modified linear aliphatic polyethers, and sorbitan esters. .

According to another aspect of the invention, a plasticizer can also be included in the aqueous solution. The plasticizer can be selected from, for example, glycerol, glucose, polyhydric alcohol, triethanolamine, and stearate.

Alternatively, an oligomer or polymer foam modifier can be included in the aqueous solution. Examples of the foam modifier include polyethylene glycol, guar gum, albumin, gelatin, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline, You can choose from polyethylene imine. These foam modifiers can be used to improve the flexibility and toughness of the polysaccharide foam.

According to a further idea of the present invention, the foam modifier may also use polyethylene glycol functionalized with vinyl groups, such as, for example, acrylic esters. After foaming, the functionalized polyethylene glycol is polymerized by irradiation (eg, ultraviolet light or electrons) to form a polymer network in the foam. The network improves the flexibility and toughness of the foam.

According to another idea of the invention, the aqueous solution of the polysaccharide can also contain a foam stabilizer. Examples of the foam stabilizer include ammonium stearate, dodecyl alcohol, tetradecanol, hexadecanol,
It can be selected from tridecyloxy polyethanol and polyoxyethylated oleylamine.

Alternatively, the polysaccharide foam containing the foam stabilizer can be air dried after formation. During drying, "bubble breaking" of the foam material takes place in the interior area of the foam, and a broken foam appears. The bubbles that make up the foam are deformed,
The size of the bubble becomes smaller than the normal size. This change in shape is seen as a change from spherical to elliptical. When the cells change in this way, the foam becomes a "bubble destroyed" foam. The foam material arranged on the surface of the foam retains the average pore size and pore size distribution without being destroyed.

In the case of chitosan in which the polysaccharide is foamed in an acidic aqueous solution, specifically, it is desirable to remove the acid after foaming while the foam is in a wet state. During drying, the presence of acids has a deleterious effect on chitosan foam. The acid can be removed by volatilization or neutralization after foaming. In particular, when the acid is acetic acid, it can be removed by volatilization.

According to another aspect of the invention, the foam can be stabilized by cross-linking or coagulation, providing a dimensionally stable foam. In particular, the foam can be cross-linked and solidified during wetting. If a stabilizer is used, it can be crosslinked or solidified after the first drying, and the foam can then be dried again.

Where the polysaccharide is selected from, for example, alginic acid, alginate, hyaluronic acid, hyaluronic acid, and other soluble polysaccharide materials containing a displaceable counter cation, the cross-linking will Alternatively, it can be achieved by reacting with a trivalent cation. In particular,
The polysaccharide foam is immersed in a divalent or trivalent cation solution, or the solution is sprayed. The cation can be selected from Ca ²⁺ (aq), Fe ²⁺ (aq), and Fe ³⁺ (aq).

Further, for example, in the case of an insoluble carbonate or hydrocarbon salt having one or more divalent or trivalent cations, the foam is uniformly dispersed in the foamed polysaccharide, and the foam is treated with a strong acid to convert carbon dioxide into gas. Release and subsequent crosslinking of the cation with the polysaccharide can form a dimensionally stable foam structure. The strong acid can be used in a concentration of up to 1N, and particularly preferably 0.1 to 0.2N. Calcium carbonate can also be used as an insoluble carbonate. In the case of cross-linking by the latter method, there is an advantage that a relatively thick foam can be uniformly stabilized. In particular, when the foam thickness is about
In the case of up to 5 mm, this method can be stabilized homogeneously and provides a stable foam structure.

According to another aspect of the invention, cross-linked alginate and hyaluronate foams can be "modified" by aqueous treatment of a drug having a solubilized monovalent cation.
Thereby, a certain proportion of cross-linked divalent or trivalent cations in the foam can be replaced by monovalent cations. This can give the foam some solubility. When contacted with water, the modified foam becomes a gel. Specifically, the degree of modification can be controlled,
If a small percentage of the cross-linking cations are displaced, they will have a slightly gel form (when exposed to water).
Alternatively, a water-soluble foam results when all cross-linked cations are replaced. As the agent, sodium acetate or dilute hydrochloric acid can be selected.
In particular, the treatment is preferably performed at a pH of 4 to 7.

When the soluble polysaccharide is chitosan, the foam solidifies upon base treatment. Typically, the base may include sodium hydroxide. Alternatively, chitosan foam can be cross-linked by ionic or covalent bonds. Ion-bonding cross-linking can be obtained by aqueous treatment of a polyvalent anion. Particularly, polyvalent anions include sodium sulfate, octyl sulfate, lauryl sulfate, hexadecyl sulfate, tripolyphosphate, and pyrophosphate. One or more of a salt and octapolyphosphate can be used. In another example, the covalent cross-links form a chitosan foam
It can be obtained by treating with the above dialdehydes, for example, glyoxal, glutaraldehyde, dialdehyde starch and the like.

If the polysaccharide is starch, the starch foam can be coagulated by ammonium sulfate solution treatment. Alternatively, the starch foam can be cross-linked by formaldehyde treatment. This treatment is performed in a gas state or a solution state. When the treatment is performed in a solution state, an alcohol solution is particularly preferably used.

The crosslinked or coagulated polysaccharide foam can be air dried.
After drying, the dried crosslinked or coagulated foam can be washed with water and then dried again. Rinsing is performed to remove the remaining foaming agent and foam stabilizer in the foam.

The aqueous solution of the polysaccharide further comprises a particulate filler, barium sulfate, pulp-like fibers of cellulose or other fibrous materials,
It may also contain one or more ingredients selected from moisturizing or reinforcing fillers. When using barium sulfate,
The resulting foam was opaque to X-rays. The foam is therefore useful in radiography as a medical implant.

Optionally, the foam can be bleached. The bleaching agent can be contained in the aqueous solution of the polysaccharide. In particular, as the bleaching agent, hydrogen peroxide or sodium hypochlorite can be selected.

The present invention also relates to the polysaccharide foam produced according to the method of the present invention. Foam is any thickness,
Pore size and pore size distribution can be adjusted. The foam can be crosslinked or solidified. The form is
At least some of the foams can be soluble, insoluble, or "modified" foams having the desired solubility. Foams include alginates, hyaluronates, chitosan or starch foams.

According to another idea of the invention, the foam is in a wet state,
It can be cast as a layer or as a shaped article. The foam can be cast, inter alia, in the form of buttons, beads, balls, tubes, hemispheres. Furthermore, the foam can be cast into a part of the human or animal body, such as the shape of an ear or nose.

According to a particular idea of the invention, the foam can also be cast as a layer on a support. Examples of the support include woven or non-woven fiber products, films, foams, and the like. Specifically, the support is composed of an aggregate of polysaccharide fibers and yarns. According to a particular idea of the invention, the support can also be a layer of another polysaccharide foam according to the invention. The foam of the other layer may have a different average pore size and / or pore size distribution from the foam.

The foam can also be cast as a thin foam layer having a thickness of about 1 mm or less. Alternatively, the foam according to the present invention can be cast as a thick foam layer having a thickness of about 50 mm or less. The thick foam layer may also have a "bubble-broken" foam layer therein. The foam placed on the surface of the foam has a similar appearance to a freshly produced foam without significant bubble breakage, and has approximately the same pore size and pore size distribution.

The invention also relates to a wound dressing comprising a polysaccharide foam produced by the method according to the invention. In particular, the wound dressing consists of a layer of said polysaccharide foam. For example, the foam may be placed on a support consisting of a polysaccharide cloth or a polysaccharide thread.

The present invention also relates to a cell replica culture substrate produced according to the method of the present invention. Replicated cells are placed in holes in the foam to fix the cells.

Specifically, the substrate for replica culture of cells is a transplant material,
In particular, bioabsorbable implants can also be constructed.

Cultured cells, for example, mammalian cells, can be placed in holes in the implant material and then surgically implanted into the human or animal body. The graft material with the cultured cells promotes the growth of tissue in or near the graft in vivo.

The present invention is also a barrier substrate that prevents cell adhesion. Said barrier substrate comprises a polysaccharide foam according to the invention.

According to another aspect of the invention, polysaccharide foams can also be the basis for beneficial formulations. The beneficial agent can also be placed in the foam cells. In particular, if the formulation comprises a useful agent and the pharmaceutically acceptable excipient is acceptable. Furthermore, useful drugs are drugs that can be administered transdermally to patients. In particular, useful agents can be included in the aqueous polysaccharide solution prior to foaming. However, useful agents can be incorporated into the foam after formation. Specifically, the foam can be immersed in the drug (which is itself a solution) or the drug can be sprayed. Otherwise, the drug can be dispersed in the solid cells of the foam structure of the foam, or can be produced by living cells (eg, microorganisms) in the foam structure.

According to yet another aspect of the invention, the foam according to the invention can also be stored in the wet state under pressure. In particular, the wet foam can be stored in a pressurized dispenser, for example a conventional pressurized spray can. In addition, the wet foam can be mixed with a propellant to facilitate discharging the foam from the dispenser. As the propellant, stable propellants known to those skilled in the art, such as gaseous lower alkanes (such as propane, butane, and pentane), nitrogen, and carbon dioxide, can be used. Preservation under pressure can be carried out in the usual way of preserving wet foam prior to use. If necessary, it can be simply collected directly in the environment of use.

For example, a wet foam wound dressing according to the present invention can be stored under pressure in a dispenser or can be applied directly to the skin of a patient (eg, scuffed skin, burns, open wounds). . Wet foams with the beneficial agents according to the present invention can also be stored and prescribed on demand in a manner similar to that used for treating wounds and other injuries. Foam wound dressings and beneficial formulation bases stored in an airtight dispenser are particularly suitable for the purpose of being primarily applied to a patient in an emergency.

Hereinafter, the present invention will be described in detail with reference to examples. The drawings illustrate the effects of the present invention.

Drawings FIG. 1 is a scanning electron microscope (SEM) photograph of the surface of a single layer foam made according to the present invention.

FIG. 2 is a scanning electron micrograph of another surface of the monolayer foam of FIG.

FIG. 3 is a scanning electron micrograph of a section of the monolayer foam of FIGS. 1 and 2 in the thickness direction.

FIG. 4 is a scanning electron micrograph of the surface of a two-layer foam made according to the present invention.

FIG. 5 is a scanning electron micrograph of another surface of the two-layer foam of FIG.

FIG. 6 is a scanning electron micrograph of a section of the two-layer foam of FIGS. 4 and 5 in the thickness direction.

Example 1 A 3% by weight sodium alginate solution having a viscosity of 1500 centipoise was prepared, and 0.1 gram of sodium dodecyl sulfate was added as a blowing agent to 100 grams of this solution. The resulting solution was beaten with a kitchen mixer to form a foam. Spread foam on metal tray, 5% by weight
With calcium chloride solution. Thereafter, the foam was dried. The dried foam was 0.05 mm thick and 7 grams per cubic meter. Scanning electron micrographs of the crosslinked foam showed that the open pore structure was 1
It has an air permeability of 10 m / min under a pressure of 2.7 mmH ₂ O.

A part of the foam produced by the above method was
By placing the foam in a hydrochloric acid solution for 30 minutes. The modification did not affect gauge weight or pore size,
The dissolution properties were changed. Contacting the unmodified foam with a 1% sodium citrate solution did not affect structure, but contacting the modified foam with a similar 1% citric acid solution caused the foam to gel. This indicates that the solubility characteristics were changed by the modification step.

Example 2 A 3 inch × 3 inch gauze pad of 12 layers of 20 × 12 mesh fabric was used as a support for the alginate foam layer described in Example 1. The foam was spread on the dough and cross-linked with a 5% calcium chloride solution. Then it was dried. The cross-linked foam adhered to the gauze pad to form a coating.
Photomicrographs of the resulting structure showed a thin 0.05 mm thick foam coating on the gauze pad, and the structure was similar to the unsupported foam described in Example 1.

Place the coated pad in a pH 5 hydrochloric acid solution for 30 minutes.
After a few minutes, the calcium structure changed to a soluble structure.
Contacting the altered material with sodium citrate again gelled the alginate coating.

Example 3 A 2% by weight sodium alginate solution was prepared. To this solution, ammonium stearate was added as a foam stabilizer to a concentration of 0.2% by weight, and calcium carbonate was further added to a concentration of 2% by weight. Thereafter, the mixture was stirred well with a kitchen mixer to produce a foam in which calcium carbonate was dispersed. The foam was stretched on a plastic tray, and 200 ml of 0.1 N hydrochloric acid was added to the tray. The foam crosslinked by the addition of the strong acid. The dried foam had a thickness of 2.1 mm, a density of 0.22 g / cm ³ , and an air permeability of 6 m / min under a pressure of 12.7 mmH ₂ O.

 The foam had solidified homogeneously throughout.

Example 4 A 3% by weight aqueous solution of sodium alginate was prepared.
0.85 g of sodium dodecyl sulfate was added to the solution as a blowing agent per 100 g of alginate solution. In addition, 2.3 grams of ammonium stearate was added as a foam stabilizer per 100 grams of alginate solution.
The resulting solution was beaten with a kitchen mixer to form a foam. The foam was spread on a polyester sheet and air dried. The surface of the dried foam had a similar appearance to the wet foam and there was no bubble breakage. The foam material inside the foam had been "bubble broken" and had the appearance of a broken foam. The dried foam was immersed in a 5% by weight calcium chloride solution and air-dried. The dried foam again had the appearance of the original stretched material. Observation with an optical microscope indicated that the foam had an open cell structure with fairly uniform pore size. The foam finally had a thickness of 2.8 mm, a density of 0.05 g / cm ³ and a permeability of 90 m / min under a pressure of 12.7 mm H ₂ O.

Example 5 To a solution having the same composition as in Example 1 was added 1 gram of anhydrous glycerol per gram of alginate. The solution was mechanically foamed, stretched to the desired thickness, and air dried. The dried foam was crosslinked with a 5% by weight calcium chloride solution and air dried. The resulting foam finally has a thickness of 0.25 mm, a density of 0.14 g / cm ³ and a permeability of 12.7 mm H ₂ O under pressure
It was 100 m / min. After 3 months under ambient conditions, the foam had the same handling properties as the newly created foam.

Example 6 A single layer alginate foam was prepared in a manner similar to that described in Example 4 above. 1 to 3 are scanning electron micrographs of the obtained dried foam (10).
It can be seen that the interior region (12) of the foam is "bubble-broken", which assumes the appearance of a "broken" foam. on the other hand,
The surface (14, 16) of the foam has the original pore size and pore size distribution.

Example 7 Another alginate foam layer was produced by a method similar to that of Example 4 above. The first foam layer was mechanically foamed and dried according to the invention to have a relatively large average pore size. The second foam layer had a relatively small average pore size and was then cast over the surface of the previous layer and dried. 4 to 6 are scanning electron micrographs of the obtained two-layer foam (20). The inside of the foam (22) is "bubble broken" but the surface (24, 26)
Had the original pore size and pore size distribution.

Example 8 A 5% by weight aqueous solution of sodium hyaluronate was prepared. To this solution was added 2.7 grams of sodium dodecyl sulfate and 5.3 grams of ammonium stearate per 100 grams of solution. The mixture was beaten well with a kitchen mixer to form a foam. The foam was spread on a polyester sheet and air dried. According to observation with an optical microscope,
The foam had an open cell structure with fairly uniform pore size.

Example 9 A solution was prepared consisting of 10 grams of 37.5 w / w HCl and 490 grams of water. The acid solution was added and dissolved with 15 grams of chitosan. To the solution was added 1.5 grams of sodium dodecyl sulfate and 15 grams of ammonium stearate.
The mixture was beaten with a kitchen mixer to form a foam. The foam was then stretched to a thickness of 25 mils and air dried. Observation with an optical microscope indicated that the foam had an open cell structure with fairly uniform pore size.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Jeffery Andrew Blues Marina Drive, North Quincy, MA, USA, USA 2001 (72) Inventor Marmingis Constantinos United States, Massachusetts, Boston, St. Stephens Street 121, No. 17 (72) Inventor Haghurt Thomas Henry South Mountain Avenue, Montclair, NJ, United States 77 (56) References JP-A-62-167331 (JP, A) JP-A-62-81432 (JP, A) Ryogo Kubo, 3 editors, "Iwanami Physical and Chemical Dictionary 4th Edition", Iwanami Shoten (October 12, 1987), page 874, right column-page 875, left column, Chemical Dictionary Committee ed., "Chemical Dictionary 5" Kyoritsu Shuppan (1972 September 15) 133, right column,

Claims (54)

(57) [Claims] 1. A method for forming a continuous polysaccharide foam from an aqueous solution of a polysaccharide, comprising the steps of: a) generating an aqueous solution of a polysaccharide; b) introducing a gas into the aqueous solution and forming a wet foam by stirring; c. A) dispersing uniformly the insoluble carbonate or bicarbonate having one or more divalent or trivalent cations in the wet foam, and subsequently treating the wet foam with an acid having a concentration not exceeding 1 N; Releasing carbon dioxide and cations as a gas to form a crosslinked polysaccharide foam, d) drying the wet foam to form a dried polysaccharide foam, wherein the dried polysaccharide foam comprises: A method characterized by being mainly composed of a polysaccharide. 2. The method according to claim 1, wherein the formation of the wet foam is promoted by beating or mechanical stirring. 3. The polysaccharide comprises a soluble polysaccharide salt, soluble alginate, soluble hyaluronate, alginic acid, hyaluronic acid, carrageenan, chitosan, starch, amylose, guar gum, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and amylopectin. 2. The method according to claim 1, wherein the method is selected from the group. 4. The method according to claim 1, wherein the polysaccharide is chitosan foamed in an acidic solution. 5. A starch, wherein the polysaccharide is foamed in a basic solution,
2. The method according to claim 1, wherein the method is selected from the group consisting of amylose and amylopectin. 6. The method according to claim 1, wherein the aqueous solution of the polysaccharide contains at least one drug selected from the group consisting of a foam stabilizer and a foaming agent. 7. An aqueous solution comprising sodium stearate, sodium dodecyl sulfate, α-olefin sulfate, sulfoalkylamide, monocarboxyl coco imidazoline compound, dicarboxyl coco imidazoline compound,
The method according to claim 1, comprising a blowing agent selected from the group consisting of sulfated aliphatic polyoxyethylene quaternary nitrogen compounds, octylphenol ethoxylate, modified linear aliphatic polyethers and sorbitan esters. 8. The method according to claim 1, further comprising introducing a plasticizer selected from the group consisting of glycerol, glucose, polyhydric alcohol, triethanolamine and stearate into the aqueous solution. 9. An aqueous solution selected from the group consisting of polyethylene glycol, guar gum, albumin, gelatin, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline and polyethyleneimine. The method of claim 1 further comprising introducing a modified oligomer or polymer foam modifier. 10. A polyethylene glycol functionalized with a vinyl group is introduced as a foam modifier, and the foam is irradiated with ultraviolet light or an electron beam to polymerize the functionalized polyethylene glycol to form a polymer network in the foam. The method of claim 9. 11. An aqueous solution selected from the group consisting of polyethylene glycol, guar gum, albumin, gelatin, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline and polyethyleneimine. The method of claim 1 further comprising introducing a modified oligomer or polymer foam modifier. 12. A polymer network formed in a foam by introducing polyethylene glycol functionalized with a vinyl group as a foam modifier and irradiating the foam to polymerize the functionalized polyethylene glycol. The described method. 13. An aqueous solution of ammonium stearate,
The method of claim 1, further comprising introducing a foam stabilizer selected from the group consisting of dodecyl alcohol, tetradecanol, hexadecanol, tridecyloxy polyethanol, and polyoxyethylated oleylamine. 14. The method of claim 1 wherein the polysaccharide foam is crosslinked to form a water-insoluble foam. 15. The polysaccharide is selected from the group consisting of alginic acid, soluble alginate, gelatin and other soluble polysaccharides containing a displaceable counter cation, and the cross-linking of the polysaccharide forms a divalent or trivalent cation. 15. The method according to claim 14, which is carried out by reacting 16. The crosslinked foam is converted by treating the foam with an aqueous solution containing a solubilized monovalent cation,
15. The method of claim 14, wherein at least a portion of the crosslinked divalent or trivalent cation in the foam is replaced by a monovalent cation, thereby imparting solubility in the foam. 17. The method according to claim 14, wherein the polysaccharide foam is chitosan treated with a base. 18. The polysaccharide is chitosan, and the chitosan foam is selected from the group consisting of sodium sulfate, octyl sulfate, lauryl sulfate, hexadecyl sulfate, tripolyphosphate, pyrophosphate, octapolyphosphate, and mixtures thereof. 15. The method according to claim 14, wherein crosslinking is performed by ionic bonding by treatment with an aqueous solution of a polyvalent anion. 19. The method of claim 15 wherein the polysaccharide is chitosan and the chitosan foam is covalently crosslinked by treatment with a dialdehyde selected from the group consisting of glyoxal, glutaraldehyde and dialdehyde starch. 20. The method of claim 14, wherein the polysaccharide is starch and the starch foam is coagulated by treatment with aqueous ammonium sulfate. 21. The method according to claim 14, wherein the polysaccharide is starch, and the starch foam is crosslinked by treatment with formaldehyde in an alcoholic solvent. 22. The method of claim 14, wherein the crosslinked foam is washed and then dried. 23. The method according to claim 16, wherein the converted and crosslinked foam is washed and then dried again. 24. The method of claim 1, further comprising crosslinking the wet foam to form a crosslinked wet foam. 25. The polysaccharide is selected from the group consisting of alginic acid, soluble alginate, gelatin and other soluble polysaccharides containing a displaceable counter cation, and the cross-linking makes the wet foam a divalent or trivalent cation. 25. The method according to claim 24, wherein the method is carried out by reacting 26. The insoluble carbonate or bicarbonate having one or more divalent or trivalent cations is dispersed homogeneously in the wet foam, and the wet foam is subsequently treated with an acid having a concentration not exceeding 1 N. 25. The method of claim 24, further comprising treating, thereby releasing carbon dioxide and cations as gases, which then form a crosslinked polysaccharide foam. 27. The method of claim 24, further comprising washing and drying the crosslinked wet foam to form a dry continuous polysaccharide foam. 28. A crosslinked wet foam is converted by treating the foam with an aqueous solution containing solubilized monovalent cations, such that at least a portion of the crosslinked divalent or trivalent cations in the foam is 1%. Replaced by a valent cation,
Claims that thereby impart solubility in the foam
The method of 25. 29. The method of claim 28, further comprising washing and drying the converted, crosslinked wet foam to form a dry continuous polysaccharide foam. 30. Pulp-like fibers of particulate filler, barium sulfate, cellulose or other fibrous material, humectant,
2. The method according to claim 1, wherein at least one component selected from the group consisting of: and a reinforcing filler is introduced into an aqueous solution. 31. The method of claim 1 wherein the wet foam is cast as a layer and dried to form a dry continuous sheet of polysaccharide foam. 32. The method according to claim 1, wherein the wet foam is cast in the form of a button, bead, ball, cylinder or hemisphere or in the form of a part of a human or animal body and dried. 33. The method of claim 1, wherein the wet foam is cast as a layer on a support and dried. 34. The method according to claim 33, wherein the support is a woven or non-woven textile, film, or foam. 35. The method of claim 34, wherein the support is a layer of polysaccharide foam having a different average pore size or pore size distribution than the cast foam layer. 36. The method according to claim 1, wherein the preparation is introduced into an aqueous solution. 37. The method according to claim 1, wherein the preparation is introduced into a polysaccharide foam. 38. A dry continuous polysaccharide foam produced according to the method of claim 1. 39. A wound dressing, cell replica culture substrate, barrier substrate or drug substrate consisting essentially of the polysaccharide foam produced according to the method of claim 1. 40. A wound dressing, cell replica culture substrate, barrier substrate or drug substrate consisting essentially of the polysaccharide foam produced according to the method of claim 14. 41. A wound dressing, cell replica culture substrate, barrier substrate or drug substrate consisting essentially of the polysaccharide foam produced according to the method of claim 24. 42. A method of forming a wet polysaccharide foam stored under pressure according to the method of claim 1, further comprising storing the wet foam under pressure. 43. The method according to claim 42, wherein the formation of the wet foam is promoted by beating or mechanical stirring. 44. The polysaccharide comprises a soluble polysaccharide salt, soluble alginate, soluble hyaluronate, alginic acid, hyaluronic acid, carrageenan, chitosan, starch, amylose, guar gum, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and amylopectin. 43. The method according to claim 42, wherein the method is selected from the group. 45. An aqueous solution comprising sodium stearate, sodium dodecyl sulfate, α-olefin sulfate, sulfoalkylamide, monocarboxyl coco imidazoline compound, dicarboxyl coco imidazoline compound, sulfated aliphatic polyoxyethylene quaternary nitrogen compound,
43. The method of claim 42, comprising a blowing agent that promotes the formation of a foam selected from the group consisting of octylphenol ethoxylate, modified linear aliphatic polyethers and sorbitan esters. 46. Glycerol, glucose,
43. The method according to claim 42, further comprising introducing a plasticizer selected from the group consisting of polyhydric alcohols, triethanolamine and stearates. 47. An aqueous solution comprising ammonium stearate,
43. The method of claim 42, further comprising introducing a foam stabilizer selected from the group consisting of dodecyl alcohol, tetradecanol, hexadecanol, tridecyloxy polyethanol and polyoxyethylated oleylamine. 48. Granular fillers, pulp-like fibers of barium sulfate, cellulose or other fibrous substances, humectants,
43. The method according to claim 42, wherein at least one component selected from the group consisting of: and a reinforcing filler is introduced into the aqueous solution. 49. The method according to claim 43, wherein the preparation is introduced into an aqueous solution. 50. The polysaccharide foam, wound dressing, cell replica culture substrate, barrier substrate or drug substrate according to claim 41, wherein the wet foam is stored in a pressure dispenser. 51. The method according to claim 42, wherein the wet foam is stored in a pressurized spray can. 52. The method according to claim 51, wherein the wet foam is mixed with a propellant selected from the group consisting of gaseous lower alkanes, nitrogen, and carbon dioxide. 53. The method further comprising introducing a polyethylene glycol functionalized with a vinyl group as an oligomer or polymer foam modifier, and irradiating the wet foam with a UV or electron beam after releasing the foam from storage. 43. The method according to claim 42, wherein the polymerization of the polyethylene glycol is performed to form a polymer network in the foam. 54. A wound dressing, cell replica culture substrate, barrier substrate or drug substrate consisting essentially of the polysaccharide foam produced according to the method of claim 42.