ENZYMINHIBIERENDE ADHESIVES

This invention relates to an adhesive for use in an ostomy or wound care device, in particular, an adhesive which contains enzyme inhibitors.

The peristomal, perianal, and perineal skin in subjects with an ostomy or fecal incontinence, and infants wearing diapers can be continuously exposed to feces. When this occurs, the skin is attacked by the contents of feces, mainly the proteolytic or digestive enzymes. This leads to erosion of the skin surface resulting in severe skin conditions, such as dermatitis. Similar skin erosion could also occur in peri-wound skin in a wound environment.

In the case of ostomates, a variety of products are used in an attempt to protect the skin from fecal or urine contact. These include adhesive wafers, lotions, creams, pastes, rings, barrier wipes, etc. However, all of these methods of protection only offer a physical barrier to enzymatic attack. When the physical barrier wears out or breaks, the enzymatic attack is imminent. In the case of ostomates, another drawback is that pre-treatments to the skin, such as lotions or creams, may negatively affect the adhesion of the adhesive wafer to the skin. This can lead to premature failure by detachment of the ostomy device, which is not acceptable.

In the case of a wound, enzymes such as elastase potentially cause skin damage and retard wound healing.

The present invention is related to the protection of the skin using an adhesive composition which contains enzyme inhibiting additives while maintaining the function of the adhesive and the inhibitors.

There are numerous prior art disclosures that describe the use of enzyme inhibitors in lotions and pastes, powders, etc.

US Patent 6,723,354 and Patent Application US 2004/0166183A1 disclose the use of potato juice in the form of sprays, gel, lotions, powder, etc. for the treatment of inflammation or pruritis. The enzyme inhibition is demonstrated by adding the potato juice directly to a mixture of the enzyme.

US Patent 6,331,295 B 1 discloses the use of a solid composition for prevention of skin irritation such as diaper rash comprising an organophilic clay dispersed in a water-permeable superabsorbent polymer matrix. The organophilic clay is selected from a group consisting of natural and synthetic montmorillonite, bentonite, etc.

US Patent 6,207,596 B 1 discloses a disposable premoistened wipe containing an antimicrobial protease inhibitor such as an aromatic diamidine.

US Patent application US 2003/0206944 A1 discloses a wound dressing composed of a cotton cellulose matrix with an active agent that is an inhibitor or sequestrant of a neutrophil-derived cationic protease, such as elastase. The active agent could be inhibitors selected from a group consisting of di- and tri-peptides, or sequestrants selected from a group consisting of sulphonyl, phosphate, or aldehyde groups associated with the matrix.

US Patent application US 2004/0028708 A1 discloses the use of a skin protectant cream with an enzyme blocking compound. The enzyme blocking compound is selected from zinc sulfate, zinc chloride, zinc oxide, zinc lactate, or combinations thereof.

US Patent application US 2003/0104019A1 discloses a solid topical composition comprising a swellable clay and a peptizing agent for the treatment or reduction of enzymatic dermatitis, such as perineal dermatitis, caused by urine. The swellable clay is selected from a group consisting of pyrophillite, talc, smectite, sepiolite, zeolite, palygorskite, and mixtures thereof. The peptizing agent is selected from a group consisting of tetrasodium or potassium pyrophosphate, sodium hexametaphosphate, sodium citrate, sodium polyacrylate, etc.

These references do not suggest or disclose delivering enzyme inhibition compositions using an adhesive matrix.

The present invention relates to incorporating one or more enzyme de-activating agents based on tubers into adhesives such as hydrocolloid adhesives for wafer barrier application to the skin in ostomy and wound care. The adhesive may, for example, be included in a wafer, thin sheet or film. In addition, this invention may be used as a coupling adhesive in devices that come in contact with feces and wound exudates.

Accordingly, the adhesive composition of the present invention includes an adhesive component and an enzyme inhibiting component. The enzyme inhibiting component may be one or more inhibitors derived from tubers, such as from potatoes. The adhesive component may be a hydrocolloid adhesive that includes a rubber matrix and one or more fillers. The rubber matrix is selected from the group consisting of polyisobutylene, polybutadiene, polyisoprene, styrenic block copolymers, amorphous polyolefins, polyurethanes, acrylics, silicones, polyvinyl pyrollidone (PVP), ethylene vinylacetate (EVA), polyvinyl methylether, and combinations thereof. The fillers are hydrocolloids selected from the group consisting of carboxymethyl cellulose, sodium carboxymethyl cellulose, carboxyethylmethyl cellulose, carboxypropyl cellulose, carboxyethyl cellulose, pectin, gelatin, agar, alginate, carageenan, cellulose, guar gum, karaya gum, locust bean gum, xanthan gum, chitosan and its derivatives, starch, pullulan, beta-glucan, gellan, curdlan, and combinations thereof.

It is alternatively possible for the adhesive component to be selected from the group consisting of hydrocolloid adhesives, polyisobutylene, polybutadiene, polyisoprene, styrenic block copolymers, amorphous polyolefins, polyurethanes, acrylics, silicones, polyvinyl pyrollidone (PVP), ethylene vinylacetate (EVA), polyvinyl methylether, and combinations thereof.

Table 1 shows the composition of the adhesives used for evaluation. Adhesive A is control hydrocolloid adhesive. Adhesive B is does not contain gelatin or potato protein. Adhesive C is similar to Adhesive A where the gelatin is replaced with potato protein.

The adhesives were mixed in a Haake mixer at 230F. The polyisobutylene rubber was initially mixed followed by rest of the ingredients, once the rubber melted. Those skilled in the art will recognize that many methods of blending the ingredients are suitable for preparing these adhesives and that the process described above in no way limits the scope of the invention disclosed herein. The resulting adhesives were heat pressed between two silicone releases papers to form a sheet of about 3.5 mm thickness.

Each adhesive was cut into pieces of about 7.5 mm x 7.5 mm x 2.0 mm. The adhesive pieces were placed in separate vials. For each adhesive composition, four different enzymes, Chymotrypsin, Trypsin, Elastase, and Pepsin were tested separately. In addition, the pure protein powder was evaluated at two concentrations, 1% w/v and 4% w/v. The vials were incubated at 37C and the enzyme activity was monitored using absorption-emission spectroscopy. Tables 2 and 3 list the enzymes and their concentration used for the study, and the experimental matrix, respectively. Pepsin is released in the stomach and the other three enzymes are released by the pancreas. All of these enzymes are present in feces. Elastase is also present in wounds.

Table 4 shows the effect of adding potato protein to a pressure sensitive adhesive. It can be seen that the peel strength to stainless steel and tack for Adhesive C with 20% protein is comparable to the control Adhesive A. In addition, Table 4 shows that the tack values of conventional pressure sensitive adhesives with and without 20% w/w protein are comparable.

Charts 1-4 show that the pure protein powder has good inhibiting capability for all four enzymes at both concentrations, 1% w/v and 4% w/v. Surprisingly, it was observed that the Adhesive C, the adhesive composition with the potato protein inhibitor, shows inhibiting capabilities to all four enzymes. Furthermore, Adhesive C with the potato protein inhibitor shows increasing enzyme inhibition of all four enzymes with increasing incubation time. It can be concluded that the Adhesive C inhibits the enzyme activity of all four enzymes. It was determined by feel that Adhesive C maintains suitable tackiness to function as an adhesive.