NZ623094B2 - Discharge solidifier and malodour control - Google Patents

Abstract

Disclosed is a superabsorbent and malodour control composition in the form of an insert (104) comprising a polyacrylate superabsorbent such as sodium or calcium polyacrylate and a powdered zeolite such as ammonium zeolite and sodium aluminosilicate, wherein the superabsorbent is coated with the powdered zeolite. Also disclosed is the configuration of the insert to absorb fluids and/or solidify and gel excreted matter from the body and to control odours resultant from excreted matter which is collected in an ostomy bag. ered zeolite. Also disclosed is the configuration of the insert to absorb fluids and/or solidify and gel excreted matter from the body and to control odours resultant from excreted matter which is collected in an ostomy bag.

Description

RGE SOLIDIFIER AND MALODOUR CONTROL The present ion s to a superabsorbent and malodour control composition and in particular, although not exclusively, to a superabsorbent for solidifying collected matter excreted by the body and a control agent for controlling odours associated with the excreted .

Ostomy patients typically wear an ostomy bag into which body waste is excreted. Ostomy patients fall into three categories, each category necessitating the patient wearing an ostomy bag. Firstly, urostomy patients typically have had their bladders removed.

Accordingly in this case, urine is passed through the stoma and into the ostomy bag.

Secondly, colostomy patients have undergone surgery to remove all or part of the colon necessitating an ostomy bag to collect both liquid and solid excreted matter. Thirdly, ileostomy patients similarly rely upon an ostomy bag to t excreted matter which is redirected through the abdominal wall.

Generally an ostomy bag comprises an g which is sealed against the patient’s skin around the surgically created body orifice, termed a stoma. Many ostomy bags are ed with a discharge outlet to allow excreted matter to be emptied from the ostomy bag by the patient.

When body waste is excreted into the ostomy bag it continues to release malodours which are unpleasant and can cause embarrassment to the patient. Also, where the excreted matter is in liquid form, leakage from the ostomy bag is a potential risk which would also cause embarrassment to the patient.

A number of additives have been proposed for ostomy bags designed to solidify excreted fluid matter and reduce unpleasant malodours. US 2002/0055594 discloses a superabsorbent tablet configured to thicken body ions. The tablet ses a superabsorbent polymer in the form of cross linked sodium or calcium rylate designed to provide quick gelling of the ostomy bag contents following excretion.

US 6,852,100 also discloses an ostomy pouch configured to reduce unpleasant odours.

Superabsorbent fibres are used in combination with a malodour counteractant selected from various different categories of odour controlling ng and neutralising) agents including for e hydrogen peroxide and bacterial growth inhibiters such as sodium nitrate and benzyl alkonium chloride.

GB 2329339 discloses a superabsorbent for an ostomy bag comprising granules of a superabsorbent formed into a stick or rod and housed within a water e outer sleeve.

Odour counteractants, disinfectants and preservatives are also incorporated within the ostomy bag insert.

US 5,860,959 discloses a hydroscopic composition to reduce malodours from an ostomy bag. Water absorbing materials such as starch or alkaline metal polyacrylates are employed as bsorbents in combination with odour counteractants such as volcanic clays and activated carbon granules.

The discussion of the background to the invention included herein including nce to documents, acts, materials, s, articles and the like is included to n the context of the present invention. This is not to be taken as an admission or a suggestion that any of the material referred to was published, known or part of the common general knowledge in Australia or in any other country as at the priority date of any of the claims.

However, there exists a need for an ostomy bag insert configured to ively solidify or gel excreted matter and control unwanted malodours.

The present invention desirably provides a bsorbent material for positioning within a stoma bag exhibiting superabsorbent and odour controlling properties. The superabsorbent blend has been found to exhibit enhanced malodour reduction over existing ostomy bag inserts.

According to a first aspect of the present invention there is provided an ostomy bag insert comprising: a granular polyacrylate bsorbent; and a powdered zeolite; wherein the superabsorbent is coated with the powdered zeolite; and wherein the powdered zeolite is bound to the rylate superabsorbent by electrostatic forces.

Reference within the specification to e includes es being microporous and capable of accommodating within their structure lar species including ions and in particular s compounds typically found in faecal waste.

Optionally, the zeolite may comprise a naturally sourced zeolite mineral including in particular analcime, chabazite, clinoptilolite, heulandite, natrolite, phillipsite, and stilbite.

Optionally, the zeolite is a zeolite blend comprising a hydrophilic and a hydrophobic zeolite. Alternatively, the zeolite may be substantially hydrophilic or ntially hydrophobic. A preferred hydrophobic e comprises an ammonium zeolite being a e having ammonium groups forming part of the zeolite structure. A preferred hydrophilic zeolite comprises a sodium aluminosilicate. ally, the ostomy bag insert may further comprise powdered activated carbon.

Preferably the insert comprises the e as a major component and activated carbon as a minor component based on a dry weight percentage. Optionally, a weight % ratio of the activated carbon to the zeolite or zeolite blend, as part of the insert, is in the range 0.01:1 to 0.05:1.

The powdered zeolite may comprise a particle size equal to or less than 0.15 mm and/or 0.045 mm and/or 0.075 mm. Optionally, the e comprises a surface area of substantially 400 m2/g.

Preferably, 99% by weight of the zeolite may comprise a particle size equal to or less than 0.15mm; 95% by weight of the zeolite may comprise a particle size equal to or less than 0.075 mm and 90% by weight of the zeolite may comprise a particle size equal to or less than 0.045 mm. ably, the activated carbon comprises and is derived from coconut shell char. The activated carbon may comprise a surface area of substantially 1250 m2/g. Preferably, the polyacrylate superabsorbent ses a granular configuration being at least one or a multiple order of magnitude greater in size than the particle size of the zeolite or ted carbon.

Synergistically, the zeolite and ally the activated carbon may be bound to the superabsorbent granules by electrostatic forces. The bsorbent may comprise sodium or calcium polyacrylate. ally, the zeolite and/or the activated carbon may comprise any metal impregnated activated charcoal.

Preferably, the superabsorbent and powdered zeolite or zeolite blend is housed within a water soluble paper sachet. The paper sachet may comprise sodium carboxy methyl ose and wood pulp. The edges of the sachet may be heat sealed so as to trap the granular superabsorbent and zeolite within the envelope formed by the soluble paper.

Alternatively, the zeolite or zeolite based blend may be encased within water e films (e.g. PVA films), gel caps, plastic straws/wands or formed as tablets. Moreover, the ostomy bag insert may comprise a ity of separate units (e.g. tablets, gel caps, sachets). These units would then be inserted tely into the ostomy bag.

According to a second aspect of the present invention there is provided an ostomy bag comprising an insert as described herein. The insert may be permanently or temporarily attached to an internal wall of the ostomy bag using conventional means found in the art.

For example, the insert may be attached to the internal walls via a flap, strap or permeable pouch or cover allowing release of the superabsorbent and odour absorbing material upon contact with the excreted body fluid.

Preferably, the insert comprises 1,000 mg to 10,000 mg of the polyacrylate superabsorbent and 25 mg to 5,000 mg of the zeolite or zeolite blend. -4a- A ic implementation of the invention will now be described by way of example only, and with reference to the attached drawings in which: Figure 1 illustrates an ostomy bag comprising an insert configured to solidify liquid matter within the ostomy bag and control and reduce malodours according to a specific implementation of the t invention; Figure 2 illustrates a partial cut-away view of the ostomy bag insert of figure 1 formed as a sachet containing a granular and powdered material; Figure 3 illustrates a superabsorbent granule coated With a zeolite material; Figure 4 is a GC chromatogram of solution 1 — 3 ul/ml thioacetic acid and 0.5 ul/ml ethanethiol in water; Figure 5 is GC chromatogram of solution 2 — aqueous on containing superabsorbent polymer; Figure 6 is a GC chromatogram of solution 3 — containing activated carbon; Figure 7 is a GC chromatogram of solution 4 — containing activated carbon and bsorbent polymer; Figure 8 is a GC chromatogram of solution 5 — containing e blend; Figure 9 is a GC chromatogram of solution 6 — containing zeolite blend and super absorbent polymer; Figure 10 is a GC chromatogram of on 7 — containing hydrophobic zeolite; Figure 11 is a GC chromatogram of solution 8 containing hydrophobic zeolite and super absorbent polymer; Figure 12 is a GC chromatogram of solution 9 containing hydrophilic zeolite; Figure 13 is a GC togram of solution 10 containing hydrophilic zeolite and superabsorbent polymer; Figure 14 is a GC chromatogram of solution 11 containing CW 90 Zn salt; Figure 15 is a GC tograrn of solution 12 containing CW 90 Zn salt and superabsorbent polymer; Figure 16 is a graph of the tage decrease of ethanethiol and thioacetic acid peaks for solutions 3 to 12; Figure 17 is a graph of the percentage decrease of ethanethiol peak with increasing absorbent compound concentration; and Figure 18 is a graph of the percentage decrease of thioacetic acid peak with sing absorbent compound concentration.

The inventors provide a material blend configured to solidify excreted matter within an ostomy bag and to reduce odours within the ostomy bag which would otherwise be ed from the bag when it is emptied by a t. A material blend is housed within a water soluble sachet which provides a convenient means by which the liquid and odour absorbing material blend may be stored and transported prior to use within the ostomy bag.

The dissolvable sachet may be used in all manner of s or bags designed for collecting body excretions such as ostomy, drainage bags or other applications where body fluids require thickening or gelling and odour control (neutralisation/absorption).

Figure 1 rates an ostomy bag 100 comprising an internal chamber 105 and an inlet opening 101 surrounded by an annular adhesive pad 102. A drainage flap 103 is provided at a lower region 106 of bag 100. An odour controlling and liquid superabsorbent insert 104 is housed within internal chamber 105 and is dimensioned so as to pass through inlet opening 101 during initial insertion prior to attachment of bag 100 and h outlet opening 103 after empty and reuse of bag 100.

In use, ostomy bag 100 is d to the skin of a patient at the abdominal region, via adhesive pad 102 such that inlet opening 101 is aligned with the stoma site formed in the patient. Accordingly, excreted matter passes through the stoma and into internal chamber 105 of ostomy bag 100 via inlet opening 101.

The excreted body fluid contacts insert 104 which acts to gel (partially solidify) the fluid matter and control malodours within internal chamber 105.

Following solidification of the excreted matter, the contents of the ostomy bag 100 may then be emptied Via the flap arrangement 103 configured to dispense liquid and/or solid from internal chamber 105. Flap 103 may comprise any conventional tap or flap design configured to allow liquid and/or solid matter to be released from internal chamber 105.

Following ng ofthe bag, a new insert may then be inserted into internal chamber 105 via the flap 103 such that a user is not required to detach bag 100 from positioning around the stoma.

Referring to figures 2 and 3, insert 104 is formed as a sachet comprising a water soluble paper having an upper layer 200 and a lower opposed layer 204. The edges of the upper and lower layers 200, 204 are heat sealed 201 to define an al cavity 202 sealed along all four edges of the rectangular sachet. Insert 104 comprises liquid and odour absorbing material blend 203 (comprising a polyacrylate based superabsorbent 300 and a powdered zeolite 301) housed Within internal cavity 202 formed by the upper and lower layers 200, 203. As will be appreciated by those skilled in the art, the present invention may comprise any c polyacrylate comprising superabsorbent properties suitable for use to absorb fluids, excreted by the human body. The e may comprise any natural or synthetic zeolite or zeolite composite or blend configured to l malodours of the type associated with human body excreted matter. It is preferred that the zeolite is a blend of a hobic and a hydrophilic zeolite, Referring to figure 3, it has been found ageous for malodour control/reduction to coat the superabsorbent 300 with the zeolite 301. In particular, the superabsorbent, according to a specific implementation of the present invention, is formed as granules or s. In this configuration, the finely powdered zeolite readily coats the al surface ofthe granules or pellets providing an active blend exhibiting enhanced odour control over existing stoma bag s. The powdered e may be maintained at the outer surface of the superabsorbent granules by, in part, the electrostatic interactions between the superabsorbent and the powdered zeolite.

According to one embodiment, the stoma bag insert 104 comprises a sodium rylate superabsorbent 300. The water soluble sachet comprises sodium carboxy methyl cellulose and wood pulp comprising a thickness in a range 0.07 mm to 0.09 mm. The zeolite comprises a zeolite blend having a hydrophilic zeolite component and a hydrophobic zeolite component. The water soluble sachet comprises 2 g of sodium polyacrylate and 250 mg of zeolite.

According to a further specific embodiment, the insert 104 ses sodium polyacrylate superabsorbent 300, the same water soluble sachet as bed above, a zeolite blend having a hydrophilic and a hydrophobic component and powdered activated carbon.

EXPERIMENTAL INVESTIGATION The effect of three odour ing compounds and a superabsorbent polymer on the volatilisation of thiol and thioacetic acid from aqueous solutions have been investigated using GC ace techniques.

It was found that all three of the odour absorbing compounds and the superabsorbent polymer are effective (to a greater or lesser degree) at reducing the volatilisation of ethanethiol and etic acid from aqueous solutions at 37°C.

The most effective system for reducing the lisation of ethanethiol and thioacetic acid from aqueous solutions at 37°C was found to be a hydrophilic/hydrophobic zeolite blend combined with the superabsorbent r. This system showed around a 95% reduction of the ethanethiol peak and 100% reduction of the thioacetic acid peak.

Results indicate that at 37°C and at concentrations of above 60mg/5m1 the zeolite blend combined with r has comparable effectiveness with carbon black and polymer at suppressing the volatilisation of ethanethiol and thioacetic acid from aqueous solutions.

ANALYSIS A GC headspace analysis method was developed during the course of the investigations and used to quantify the levels of the odorous thiol nds, thioacetic acid and ethanethiol, in the headspace above aqueous samples, with and t the ce of each of the absorbing compounds. The work found that two compounds - a zeolite blend and CW90 Zn salt — gave results which were comparable to activated . Both compounds have the advantage over carbon black of being opaque/white, which should enable easier ation of stoma bags containing the compounds.

The report below, details further investigations conducted into the absorption properties of the hydrophobic and hydrophilic zeolites and the CW90 Zn salt at temperatures more y resembling body temperature and in the presence of a superabsorbent polymer.

OBJECTIVES To test the capabilities of the zeolites and the CW90 Zn salt to absorb H28, thioacetic acid, ethanethiol and skatole both in pure aqueous solutions and in the presence of a superabsorbent polymer.

METHOD A stock on of the odorous compounds H28, thioacetic acid, ethanethiol and skatole were made up at with 2 mg/ml in water. The samples were analysed using a Perkin Elmer XL40 gas chromatograph with a Zebron ZB-624 capillary GC column (30m x .32 mm x 1.8u) with an FID or.

No signals associated with H28 and skatole were observed using the method. H28 was not detected by the FID detector and skatole was insoluble in water and its low volatility meant that the concentration in the headspace at 40°C was negligible.

As a result, a second stock solution was prepared with 3 ul/ml thioacetic acid and 0.5 ul/ml ethanethiol in water only. 5ml of the stock solution was then added to each of the following compounds: Solution Odour absorbing Mass of compound Mass of superabsorbent compound (mg) polymer (mg) __-___ __—-_ ———__ __m_—_ “_m-__ _“-_Cw90 Zn salt —m-—Cw90 Zn salt Table 1: Summary of the solutions prepared, ing the odour absorbing compound employed, its quantity and the quantity of superabsorbent polymer.

The GC analysis set up was as follows for all samples: 0 ion port temperature: 140°C; 0 Carrier gas (H2) pressure 8psi; o Oven m: 0 40°C isocratic for 5min; o Ramp to 90°C at 10°C/min; o isocratic at 90°C for 2 min; 0 FID detector temperature: 240°C.

Headspace sampling was carried out as follows: 0 Equilibrium time 7 minutes with shaking; o Pressurisation 0.5 minutes; 0 Injection 0.1 minutes; 0 Withdrawal 0.1 minutes; 0 Oven temperature 37°C; 0 Needle 60°C; 0 Transfer line 60°C.

BLANK RESULTS (SOLUTIONS 1+2) Analysis of aqueous solution containing 3 ul/ml thioacetic acid and 0.5 ul/ml ethanethiol resulted in peaks at ~2.5 minutes for ethanethiol and 5.75 minutes for thioacetic acid, the results are shown in Figure 4 The same aqueous solution when added to 25mg of superabsorbent polymer showed that the polymer itself had some odour absorbing qualities without the presence of any odour absorbing compounds, as shown in Figure 5. The polymer was more effective at absorbing thioacetic acid than ethanethiol.

SUMMARY OF RESULTS Percentage decrease of tage se of thiol thioacetic acid Carbon + Pol mer Zeolite Blend “Zeolite Blend + Pol mer 5 ZeoliteH lic Zeolite H dro hilic + 32 Zeolite H drophobic 80 Zeolite H drophobic + 96 100 Cw90 Zn salt 32 50 Cw90 Zn salt + Polymer 40 100 EFFECT OF CONCENTRATION The effect of the tration of the absorbing compounds and the polymer on the level of odours compound absorption were also investigated. 5 ml of the stock solution containing ethanethiol and thioacetic acid was added to vials containing masses of odour ing compounds ranging from ~20mg to ~150mg. The results are displayed in the tables below. Note: all ments on the absorbing compounds were performed in aqueous solutions without polymer.

Activated Carbon: m_ ethanethiol eak thioacetic acid eak Zeolite Blend: Mass of compound Percentage decrease of Percentage se of m- ethanethiol eak thioacetic acid eak _——a_ _——91 —m_— Zeolite Hydrophobic: m_ ethanethiol eak thioacetic acid eak Zeolite hilic: m_ ethanethiol eak thioacetic acid eak Cw 9OZn salt: m_ ethanethiol oeak etic acid eak ——m— —-_— Superabsorbent gel: Mass of compound Percentage decrease of Percentage decrease of m_ ethanethiol eak thioacetic acid eak The performance of the absorbing compounds identified as solutions 3 to 12 are detailed in figures 6 to 15 respectively.

A summary of the percentage decrease of the ethanethiol and thioacetic acid peaks for solutions 1 to 12, based on the gas tography results of figures 4 to 15 are shown in figure 16. The effect of the percentage decrease of the ethanthiol peak with sing absorbent compound concentration is illustrated in figure 17 and the percentage decrease of thioacetic acid peak with increasing absorbent compound concentration is shown in figure 18.

SIONS No signals associated with H28 or skatole were observed using the GC headspace method.

HZS was not detected by the FID detector and skatole was insoluble in water and its low volatility meant that the concentration in the headspace at40°C was negligible.

All the odour absorbing compounds reduced the peak height of ethanethiol and thioacetic acid compared to the blank, solution 1. The polymer also reduced the peak heights of ethanethiol by 20% and thioacetic acid by 90%.

Almost all the odour absorbing compounds showed enhanced peak ion of ethanethiol and thioacetic acid with the presence of the superabsorbent polymer, the hydrophilic zeolite was the only compound which showed little to no enhancement of ethanethiol absorption by addition of polymer.

The present results indicate that the hydrophobic zeolite is more ive at reducing the ethanethiol peak than the thioacetic acid peak, whilst the hydrophilic zeolite shows the opposite effect and is much less effective at reducing ethanethiol, but effective at reducing the thioacetic acid peak.

The Zeolite blend containing both hydrophilic and hydrophobic forms (solution 5) absorbed more ethanethiol and thioacetic acid than the dual zeolites themselves.

The Zeolite blend (solution 6) ed with the superabsorbent polymer appears to be the most effective system for ng the volatilisation of thiol and thioacetic acid from aqueous solutions at 37°C. The solution showed ~ 95% reduction of the thiol peak and 100% reduction of the thioacetic acid peak. The blend was successful because the hydrophobic zeolite had a greater effect on the tion of ethanethiol and the hydrophilic zeolite a greater effect on the absorption of thioacetic acid.

At ~37°C the performances of the zeolite blend and activated carbon appear to be roughly comparable. Activated carbon is more effective at the lower concentrations (~20mg in 5ml) at reducing the volatilisation of ethanethiol and thioacetic acid, but at higher concentrations (~60-100mg) the zeolite blend performs equally as well.

Cw 90 Zn salt was the least effective of the three compounds tested and showed only minor reductions on the levels of ethanethiol. Reductions in the thioacetic acid peak height were ed. At higher trations, in aqueous solutions, the Cw 90 Zn salt performs relatively well ssing both the ethanethiol and thioacetic acid peaks. However, in the presence of the polymer it performed less well, possibly indicating an inhibiting effect of the polymer on the salt’s performance.

Generally, increasing the concentration of the odour absorbing compound decreased the lisation of ethanethiol and thioacetic acid. The exception was the hydrophilic zeolite, which reached a plateau of ethanethiol reduction at ~20%.

Claims (19)

The claims defining the invention are as follows:

1. An ostomy bag insert comprising: a granular polyacrylate superabsorbent; and a powdered zeolite; wherein the superabsorbent is coated with the powdered zeolite; and wherein the powdered e is bound to the polyacrylate superabsorbent by electrostatic forces.

2. The ostomy bag insert as claimed in claim 1 wherein the powdered zeolite comprises a particle size equal to or less than 0.15 mm.

3. The ostomy bag insert as claimed in claim 1 or claim 2 n the powdered zeolite comprises a particle size equal to or less than 0.075 mm.

4. The ostomy bag insert as claimed in any ing claim wherein the powdered zeolite comprises a particle size of equal to or less than 0.045 mm.

5. The ostomy bag insert as claimed in any preceding claim wherein the powdered zeolite is a zeolite blend comprising a hilic zeolite and a hydrophobic zeolite.

6. The ostomy bag insert as claimed in claim 5 wherein the hydrophobic zeolite is an um zeolite and the hydrophilic zeolite is a sodium aluminosilicate.

7. The ostomy bag insert as claimed in claim 1 n the zeolite comprises a surface area of substantially 400 m2/g.

8. The ostomy bag insert as claimed in any preceding claim further comprising powdered activated carbon.

9. The ostomy bag insert as d in claim 8 wherein a weight % ratio of the activated carbon to the zeolite as part of the insert is in the range 0.01:1 to 0.05:1.

10. The ostomy bag insert as d in any one of the preceding claims wherein the superabsorbent comprises sodium or calcium polyacrylate.

11. The ostomy bag insert as claimed in any one of the preceding claims, wherein the insert further comprises a water soluble paper formed as a sachet to house the superabsorbent and the zeolite.

12. The ostomy bag insert as claimed in any one of claims 1 to 10 wherein the insert further comprises a water soluble film to house the superabsorbent and the zeolite.

13. The ostomy bag insert as claimed in any one of claims 1 to 10 wherein the insert further comprises a gel cap to house the superabsorbent and the e.

14. The ostomy bag insert as claimed in any one of claims 1 to 10 wherein the insert further comprises a plastic straw/wand to house the bsorbent and the zeolite.

15. The ostomy bag insert as claimed in any one of claims 1 to 10 wherein the insert is formed as a soluble tablet.

16. The ostomy bag insert as claimed in any one of the preceding claims, wherein the insert further comprises 1,000 mg to 10,000 mg of polyacrylate superabsorbent.

17. The ostomy bag insert as claimed in any one of the ing claims n the insert further comprises 25 mg to 5,000 mg of the powdered zeolite.

18. The ostomy bag insert as claimed in any one of the preceding claims sing a metallic salt impregnated zeolite.

19. An ostomy bag comprising an insert as claimed in any one of the preceding claims.