IE45438B1 - Disinfectant and sterilizing preparations - Google Patents

Description

This invention relates to disinfectant and sterilizing preparations.

For many years chemicals have been used for killing or inhibiting the growth of microorganisms. None of the chemicals in use or proposed, however, is completely satisfactory; many chemicals do not have a sufficiently strong or extensive, activity, while those chemicals that have the widest spectrum of activity against different kinds and forms of microorganisms have undesirable properties that ' limit their use, for example, the cresols, the phenols and formaldehyde all have highly objectionable odours and are strong irritants.

A relatively recent addition to the broad spectrum microbiocides is glutaraldehyde (1,5-pentanedial). This com15 pound has a number of advantages over other broad spectrum microbiocides eg. greater physiological tolerability, but has the drawback of lack of stability in solution at the alkaline pH's at which it is biologically active at ambient temperatures: under such conditions, glutaraldehyde poly20 merises extremely readily. Its use has, been limited, therefore,to those situations where it is practicable to prepare a buffered solution of appropriate pH before use. The preparation of such Solutions has been facilitated by the provision of a solution of glutaraldehyde at a pH at which polymerisation occurs less readily but at which the biological activity is much reduced together with a sachet containing an appropriate amount of an alkaline buffer, the - 3 •i S 4 3 3 contents of the sachet being mixed with the glutaraldehyde solution immediately prior to use The main disadvantages of this arrangement are the cost of transporting the large amounts of the dialdehyde solution, and lack of flexibility in making up solutions of different volumes.

It has been proposed to provide a dry dialdehyde preparation by spray drying the dialdehyde in the presence of an acid salt of an inorganic, sulphur-containing acid The resulting product is the adduct of the dialdehyde and tha acid. This too, is not satisfactory, however, because the adduct does not dissociate sufficiently readily, and even when it does dissociate, the bisulphite released renders the dialdehyde biologically inactive.

The present invention provides a solid composition suitable for use in making up a microbiocidal solution, or dispersion, which comprises (a) a saturated dialdehyde having from 2 to 6 carbon atoms absorbed and/or absorbed on an inorganic or organic carrier material or on a mixture of two or more such carrier materials, and (b) an alkalinating agent or agent capable of yielding aa alkalinating agent on admixture with a solvent for the dialdehyde, the or each carrier material being capable of adsorbing and/or absorbing the dialdehyde to give a substantially dry free-flowing particulate material that on subsequent admixture with a solvent for the dialdehyde substantially releases the dialdehyde.

The aldehyde is , for example, maIonaIdehyde, succinaldehyde, adipaldehyde, glyoxal but is preferably glutaraldehyde.

AA ϋ ti Ο O /. 4 ..1 I r ’ r The carrier material or matrix may be an organic F; substance, for example, a natural or synthetic polysaccharide, for example, a starch, for example, maize starch, or a cellulose derivative, for example, methylcellulose or carboxy5 methylcellulose,· but in general inorganic carriers are preferred. The preferred inorganic carries or matrices fall into two categories, which overlap to a certain extent; (i) the anhydrous salts and those salts possessing higher or lower levels of hydration and that are capable of taking up water, and (ii) the adsorbent and/or absorbent both natural and synthetic It will be appreciated that any salt used must not interfere with the achievement of the desired pH on addition of a solvent or dispersing agent, nor must the salt be so strongly alkaline that the dialdehyde is especially predisposed to polymerize either in the solid state or on solution. The preferred salts are sodium sulphate and potassium sulphate; anhydrous sodium sulphate being particularly preferred on account of the high degree of hydration possible. These salts also have the advantage of being water soluble, so provided that all the other components used are water soluble, the solid composition of the invention is water soluble.

This is advantageous with regard to subsequent use of the biocidal preparation, particularly if it is to be sprayed, A preferred solid composition of the invention comprises glutaraldehyde adsorbed and/or absorbed on sodium sulphate, and sodium bicarbonate microencapsulated in polyvinylalcohol or polycinylpyrrolidone. This composition is water soluble.

The preferred mineral carriers or matrices are various forms of silica, for example, diatomaceous earth, keiselguhr, - 5 fumed silica, precipitated silica, heetorite, bentonite, attapulgite, the montmorillonite clays, fuller's earth, and sol- and gel-forming grades of synthetic heetorite, for example, Laponite XLG and XLS, of which diatomaceous earth, fumed silica, precipitated silica, and sol- and gel-forming grades of synthetic heetorite are particularly preferred. (Laponite is a Trade Mark). Other minerals which fulfil the above requirements may also be used, for example, talc, chalk, kaolin, china clay, and whitings.

In some cases the carrier itself may function as the alkalinating agent and/or may incorporate the alkalinating agent. An alkalinating agent present in this form is called herein an internal alkalinating agent. The amount of alkalinating agent present in such a form may be sufficient to achieve the desired pH on solution or dispersion of the composition, or it may be necessary to add some further, external alkalinating agent. Examples of carriers which fall into this category are the synthetic hectorites which comprise a peptiser, especially tetrasodium pyrophosphate for example, Laponite XLS.

When the solid composition is brought into liquid or gel form for use, the preparation must be alkaline at ambient temperature, i.e. it must have a pH of more than 7, and it is also preferable that the pH does not exceed 9.5. The alkalinating agent therefore, should be one suitable for producing such pH values, and it is advantageous to use an alkalinating agent that has buffering properties. The preferred alkalinating agents are the alkali metal carbonates, bicarbonates and phosphates either alone or in any mixture of two or more thereof. Sodium bicarbonate and tetrasodium pyrophosphate are particularly advantageous. - 6 Ina preferred form of the composition of the invention, the alkalinating agent is encapsulated or coated, especially micro-encapsulated. ' The material to be used to encapsulate the alkalinating agent must be capable of releasing the alkalinating agent in the solvent for the dialdehyde, and is preferably soluble therein. The medium most generally used to prepare a liquid preparation is water, which is a solvent for the dialdehydes in question, so the encapsulating or coating material is preferably soluble in water, including hot water. Examples of suitable encapsulating and coating agents are gelatin and cross-linked gelatine, emulsified fats, hardened tallow, calcium alginate (in the presence of sodium ions), and preferably polyvinyl pyrrolidone and polyvinyl alcohol.

It will be understood that the amount of the various components in the composition will depend, inter alia, on the strength of the dialdehyde solution to be produced the relative strengths of the dialdehyde and the alkalinating agent, and the adsorptivity and/or absorptivity of the carrier material or mixture of carrier materials used. Broad limits, given as a general indication only, are as follows, the values being percentages by weight calculated on the weight of the composition; Carrier material, salt/mineral 5 - 75% Carrier material, salt 70 - 90% Carrier material, mineral 0.5 - 50% Dialdehyde (active) 5 - 30% Encapsulated buffer were appropriate 0.5- 10% The compositions of the invention may comprise one or 30 more further substances, for example, selected from anionic, cationic non-ionic and amphoteric surfactants, especially 434 33 - 7 sodium lauryl sulphate, corrosion inhibitors, defoaming agents, chelating agents, dyes and perfumes, and other biocidal substances, for examples, insecticides, nematocides and molluscicides. Surfactants are particularly useful because when the composition is made up in liquid form and applied, they assist in wetting any microorganisms with which the dialdehyde comes into contact, which facilitates the initial contact. Surfactants also aid penetration of the dialdehyde to the microorganisms if it is protected by detritus or other material. It will be appreciated that any material incorporated in the composition must be compatible with the dialdehyde and should not adversely affect the performance, storage characteristics or general acceptability of the composition to a significant extent. Accordingly, hygroscopic materials and those capable of reacting with the dialdehyde are undesirable.

The compositions of the invention are substantially dry, particulate materials, eg. powders or granules. They are preferably free-flowing. It is advantageous to dispense the composition in unit dose form, for example, in sachets or as tablets or capsules.

The compositions are prepared by admixing the dialdehyde and the carrier or matrix material, and then where appropriate admixing the alkalinating agent.

The invention also provides a solid composition comprising a saturated dialdehyde having from 2 to 6 carbon atoms adsorbed and/or absorbed on a carrier material (a) as defined above or on a mixture of two or more such carrier materials, especially those capable of functioning as the alkalinating agent and/or incorporating the alkalinating agent. - 8 The invention further provides a two-pack system which comprises a pack comprising a dialdehyde adsorbed and/or absorbed on a carrier material according to the present invention together with a pack comprising one or more alkalinating agents. The pack preferably comprises instructions indicating the amounts to be used of the two components and of the solvent or dispersing agent. Preferably both the dialdehyde component and the alkalinating agent are in un.· t· dose form.

Although in some cases it is possible to use the solid dialdehyde/alkalinating agent composition itself, it is generally necessary to bring it into a liquid or gel form for use as a biocide. The solid dialdehyde/alkalinating agent composition of the invention may be admixed with a dialdehyde solvent to give a solution, if all the other components are also soluble in the medium or a dispersion if they are not. Wafer is the solvent generally used, but under some circumstances another solvent e.g. an aqueous alkalonal may be preferred. It is also possible to prepare a stable fluid dispersion in an appropriate medium. It will be appreciated that in some cases for ease of application it is preferable to have a solution or a homogeneous dispersion.

This is especially important if the biocide is to be sprayed.

An alternative form of biocidal preparation is a gel, particularly a thixotropic gel, which has all the advantages known for preparations of this type. Some of the inorganic carriers mentioned above, for example, fumed silica and Laponite XGL and XLS, are thixotropic gel-forming agents.

The dialdehyde preparation of the invention and the two30 pack system of the invention give liquid and gel biocidal preparations as described above. In the former case, it is - 9 ,43433 necessary to admix an alkalinating agent as well as the solvent or dispersing agent.

The pH of the biocidal preparations should not be less than 7, preferably not less than 7.4, and preferably should not exceed 9.5.

All liquid and gel biocidal preparations obtained from the compositions and two-part systems of the invention are themselves part of the invention.

The dialdehydes used in the invention and especially glutaraldehyde are capable of killing bacteria and fungi, and even viruses and bacterial activity. In general, liquid preparations and gels comprising from 0.05 to 0.25% of active dialdehyde are suitable for disinfection involving killing fungi and vegetative forms of bacteria, but higher concentrations, generally up to 0.5% may be used. If a sterilizing preparation capable Of killing viruses and spores is desired, the concentration of active dialdehyde should be about 2% but again, higher concentrations, for example, up to 5%, may be used under certain circumstances.

The biocidal preparations of the invention, both the liquids and the gels, and even the compositions themselves in some cases, may be used to disinfect or sterilize articles and surfaces, for example, in domestic, industrial, medical, agricultural and horticultural situations. In the home, the solutions may be used as disinfectants in the usual manner, for example, to disinfect floors and lavatories. In the medical field in the broadest sense, that is to say, in human and veterinary medicine and surgery and in dentistry, the preparations may be used to disinfect walls, floors and non-surgical or medical apparatus e.g. beds and bedpans, and more concentrated solutions may be used to sterilize - 10 45-133 instruments and apparatus. Disinfection and sterilization of walls, floors and.plant is particularly important in the food, dairy, brewing and pharmaceutical industries.

The biocidal preparations of the invention have numerous applications in agriculture and horticulture, for example, they may be applied,to seeds, soil, crop areas and adjacent areas, and to post-harvest crops to prevent and/or combat infection by bacteria, fungi or viruses. Fruit and vegetables are particularly susceptible to deterioration caused by micro10 organisms, the yam being perhaps the most susceptible of all. For the treatment of crop areas and adjacent areas it is advantageous to incorporate an insecticide in the preparation and for treatment of soil to incorporate a nematocide. Another aspect of the use of the solutions in agriculture is in animal health, particularly in situations where animals are reared intensively, especially in poultry rearing. In the latter case, the dialdehyde may be used topically on the poultry, and is particularly effective when sprayed into the broiler house. It is also useful as a medium in which eggs are washed, as such disinfectant washing reduces the risk of infection of the egg with bacteria, particularly salmonellae. The biocidal preparations are also useful as disinfectants of farm buildings and plant, and is particularly useful for the widespread disinfection required in outbreaks of virus diseases, for example, foot-and-mouth disease, swine vesicular disease and Newcastle disease (fowl pest).

The biocidal preparations may be used topically in animal health care, as indicated above, and may also be used topically in the treatment of bacterial, fungal and viral infections of man. The invention accordingly provides a pharmaceutical preparation which comprises a liquid of gel biocidal preparation of the invention, in admixture or - 11 conjunction with a pharmaceutically suitable carrier. The preparation may be a solution or dispersion, for example, for treating athletes' foot, but in some circumstances it is advantageous to use a gel, which can be applied easily to the desired area and to that area only, for example, in the treatment of warts and ringworm.

It is to be understood that the invention includes the methods of disinfection, sterilization and treatment described above.

The concentration of the dialdehyde, the nature of the carrier or matrix and encapsulating material and the additives, if any, are chosen having regard to the use to be made of the resulting solution, for example, it is clearly undesirable to use a carrier that forms a precipitate or an encapsulating agent thatforms a gummy precipitate if the solution is to be applied by spraying The provision of the composition in unit dosage form assists the selection and preparation of a solution suitable for a particular task.

The following Examples illustrate the invention. (Cab-o-sil, Tween andDiteo are Trade Marks).

Example 1 g of anhydrous sodium sulphate were mixed with 5 g of fumed silica (Cab-O-Sil M-5) and 20 g of a 50% solution of glutaral-dehyde was sprayed on to this mixture with continuous agitation. When three components were mixed intimately, g of sodium lauryl sulphate were added and mixed, and then g of an 80:20 (w/w) sodium bicarbonate: polyvinyl pyrrolidone encapsulated buffer. The product was 100 g of a dry, free-flowing substantially white powder.

Example 2 The composition described in Example 1 was prepared by 3 13 3 - 12 i adding the anhydrous sodium sulphate to the aqueous glutaraldehyde and then·mixing in the fumed silica. The resultant powder was then mixed with the sodium lauryl sulphate and finally the encapsulated buffer.

Example 3 The composition described in Example 1 was prepared by mixing the fumed silica with the aqueous glutaraldehyde and then adding the anhydrous sodium sulphate. The resultant powder was then mixed with the sodium lauryl sulphate and finally the encapsulated buffer.

. Examples 4 to 6 The compositions described in Examples 1 to 3 were prepared but with the omission of the microencapsulated buffer, which is added at the dissolution stage prior to use.

Example 7 parts by weight of a 50% aqueous glutaraldehyde solution were stirred into 10 parts by weight of Laponite XLS. The product was a substantially white, dry, free20 flowing powder.

Example 8 The composition described in Example 7 xvas prepared and with it was mixed 0.5 parts by weight of sodium lauryl sulphate. The product was as described in Example 7.

Examples 9 to 23 Compositions were prepared as described in Example 1 but having the following formulations, the values being parts by weight. The parts by weight of the aldehyde are those contained in a 50% aqueous solution thereof. i 5 4 3 3 Example Glutaraldehyde Glyoxal Cab-O-Sil Laponite XLS Laponite XLG Diatomaceous earth Na2SO4 K2SO4 PVP/NaHCO 11 12 13 14 15 16 17 18 19 20 21 22 23 5 5 10 10 10 10 10 20 20 20 20 20 20 33 24 50 24 5 70 72 75 70 70 70 70 70 35 30 - 65 333333333 2.966 10 10 3 222 2-22222- 2 Na lauryl sulphate All the products were substantially white, dry, free-flowing powders.

Examples 24 to 38 Compositions were prepared having the formulations given for Examples 9 to 23 except that polyvinyl alcohol microencapsulated sodium bicarbonate was substituted for polyvinylpyrrolidone microencapsulated sodium bicarbonate. All the products were substantially white, dry, free-flowing powders.

Examples 39 to 49 These Examples illustrate the biocidal activity of preparations of the invention. The compositions referred to in these Examples correspond to the above formulations as follows: TOSPEC TME 10 FB TME 10 TME 5 PB TME 5 TME 2 Example 17 Example 32 Example 9 Example 24 Example 22 In these Examples I.E. stands for Inactivation Factors, BDMA/BS for British Disinfectant Manufacturers Association/ 4513 3 - 14 British Standard, ATCC for American Type Culture Collection and NCTC for National Culture Type Collection.

Example 39 BACTERICIDAL ACTIVITY TOSPSC TME 10 PB 5 Test Material : TOSPEC TME 10 PB in tap water.

Contact Time : 2 - 30 mins Temperature : 20° Test Organism ; Group II Micrococcus Inactivator ; Double Strength Nutrient Broth + 3% Tween SO 10 Recovery Medium : Nutrient Agar + 3% Tween 80 Incubation : 72 hours at 37° RESULTS Contact time SURVIVORS PER ML 15 (minutes) % Active 0.25% 0.1% 0.05% Con. Con'cn TME 10 1:40 1:100 1:200 0 3 x 106 3 x 106 3 x 106 3 X lo6 2Q 0 24,5000 3 X io6 10 „00 3 X 10® 0 20 30 0 0 0 3 X 10® Protocol θ ml of nutrient broth containing 3 x 10 organisms per ml added to 99 ml of test solution. Contact time allowed, then removed for 1 ; 100 serial dilution in inactivator solution.

Transfer 1 ml of final dilution to recovery medium.

Results mean of triplicate. - 15 Example 40 SPORICIDAL ACTIVITY OF TOSPEC UNDER HEAVY CONTAMINATION Test Materials ; Tospec TME 10 and Tospec TME 5 Concentration ; 2% active Contact time s 2 hours and 3 hours Temperature ; 2O°C Test Organism : mixed aerobic spores Contamination : 25g of mixed vegetable detritus per lOOg of test solution.

Inactivator : Double strength Lethen Broth Recovery medium : Nutrient Agar + 3% Tween 80 Challenge ; spores in above contamination Incubation : 72 hours at 35°C Control ; (a) Domestos 1% active chlorine. (b) Glutaraldehyde (UC) 2% Active.

RESULTS MEAN COUNT SURVIVORS PER ML Test material 2 hours 3 hours Tospec TME 5 5,900 <100 Tospec TME 10 2,400 <100 Domestos (Trade Mark) 116,000 84,000 Glutaraldehyde 69,000 27,000 Water 480,000 480,000 SPORICIDAL ACTIVITY TOPEC TME 5 PB (1) (2) Test Procedure Test Material Contact time Temperature Test organism Capacity type Sporicidal Tospec TME 5 PB TME 5 PB 2 hours Initial 55°C cool- 18°C at 2 hours ing to Mixed aerobic spores B Subtilis Mixed vegetable detritus from Organism origin waste trolleys at ATCC Mars Mill, Rochdale.

- IS - SPORICIDAL ACTIVITY TOPEC TME 5 PB Organic material (1) Spores held in 3g of above dust. (2) none 5 Inactivator Double strength Double strength Nutrient Broth Nutrient Broth Recovery medium Nutrient agar + Nutrient agar + 3% 3% Tween 80 Tween 80 Incubation 72 hours at 35°C 72 hours at 35°C 10 Active concentra- 2% 2% tion RESULTS Experiment 1 Experiment 2 Test Material Mean Count Mean count 15 and controls survivors ml survivors ml 15 Tospec TME 5 0 6.2xlO4 0 108 Tap Water 6.2x10 10 Freshly prepared alkaline 20 glutaraIdehyde 0 6.2x10 1,100 PROTOCOL The innoculum was added to 100 ml of test solution (2% TOSPEC in Water). The suspension was periodically agitated. Triplicate 1 ml aliqots ι were removed and serially diluted 1:100 in inactivator 1 Triplicate 1 ml aliquots of the final dilution were added to 9 ml of recovery medium for incubation. - 17 Example 42 BACTERICIDAL ACTIVITY OF TOSPEC TME 5 AND TME 10 Test procedure Test Material BDMA/BS 3286 Tospec TME 5 and TME 10 IO Concentration Contact time Temperature Test organism Culture origin 2%, 1%, 0.5%, 0.25% and 0.05% active 10 minutes 'O°C as indicated Leeds University collection 15 Inactivator Recovery medium Challenge Incubation RESULTS Double strength nutrient broth Nutrient broth and agar + 3% Tween 80 1 ml of overnight nutrient broth culture 72 hours at 35°C All the test organisms were killed by each of the test concentrations of both formulations within the contact time prescribed. Results table therefore applies to all test concentrations for both TME 5 and TME 10 S AUREUS DPNEUMONIAE E. COLI Ps AERUGINOSA P VULGARIS K AEROGENES S PARATYPHII Solid recovery Liquid recovery Reinnoc of broth to check stasis + + + + + + + + + + + + + + + + + + + + + CONTROL COUNTS No Growth S AUREUS E COLI Ps AERUGINOSA + Growth 9.8 x lO7/ml 3.0 x 108/ml .8 x lo8/ml ί»2 133 NOTES Tests were carried out in triplicate with 1:100 serial dilution in inactivator prior fco transfer Of final dilution to recovery medium.

Example 43 SPORICIDAL ACTIVITY. TOSPEC TME 10 PB (1) (2) Test Procedure Capacity type Sporicidal Test Material Tospec TME 10 PB Tospec TME 10 PB 10 Contact time 2 hours Temperature initial 55°C cooling to 18°C at 2 hours Test Organism Mixed aerobic spores Mixed vegetable detritus B Subtilis 15 Organism origin from waste trolleys at Mars Mill Rochdale. ATCC Organic material Spore held in 3g of above dust. None Inactivator Double strength Nutrient Broth Double strength Nutrient Broth 20 Recovery Medium Nutrient agar + 3% Nutrient agar + 3% Tween 80 Tween 80 Incubation 72 hours at 35°C 72 hours at 35°C Active concentra- 2% 2% tion RESULTS Test material Tospec TME 10 Tap Water 2% FRESHLY prepared alk Glutaraldehyde Experiment 1 Mean count survivors ml 1.F. 6.6xlO4 Λ 6.6x10 O 6.6xlO4 Experiment 2 Mean count l.F survivors ml 1x10® -108 600 /,3433 PROTOCOL The innoculum was to 100 ml of test solution (2% TOSPEC in Tap Water). The suspension was periodically agitated. Triplicate 1 ml aliquots were removed and serially diluted 1:100 in activator. Triplicate 1 ml aliquots of the final dilution were added to 9 ml of recovery medium for incubation.

Example 44 Test Procedure Test Material Contact time Temperature Test Organism Organism Origin Organic Material Inactivator Recovery Medium Challenge Incubation Protocol SPORICIDAL ACTIVITY TOSPEC TME 2 Capacity type.

TOSPEC TME 2.

Z.2 hours (Plating finished at 2 hours).

Initial 55°C cooling to 17°C at 2 hours.

Mixed aerobic spores (largely B subtilis + cereus).

Natural mixed vegetable, fibre + seed detritus obtained from cotton waste trolleys at Mars Mill, Courtaulds Ltd., Rochdale.

Test innoculum consisted of spores held in 3 g of above dust.

Nutrient broth + 3% Tween SO.

Nutrient Agar (Difco) + 3% Tween 80. g of spore containing dust/100 ml of test solution. hours at 35°C.

The spore containing dust was added to 100 ml of test material (2% active TOSPEC tap water). The suspension was periodically agitated. Duplicate 1 ml aliquots were removed and serially diluted 1:100 in inactivator with agitation. Duplicate aliquots of the first dilution were added to 9 ml of recovery medium for incubation. ¢,5 138 - 20 ΙΟ RESULTS Test material and controls Tospec TME 2 Mean count I.P. survivors/ML .8 x 10 Water 58,000 2%% freshly prepared alkaline glutaraldehyde 0 Blank 0 .8 x 10 Notes Sample prepared 43 days previously stored in open-cap container.

Example 45 SPORICIDAL ACTIVITY TOSPEC TME - 2.

Test Procedure Test Ja terial Concentra tions Contact Time Temperature Test Organism Organism Origin Organic Material Inactivator Recovery Medium Challenge Incubation PROTOCOL Capacitor Type.

TOSPEC TME - 2. 2%, 1% and 0.5% active aldehyde. hours (plating finished at 2 hours), initial 55°C cooling at 17°C at 2 hours. B subtilis spores.

Difco Lab. (ATCC).

None.

Nutrient broth + 3% Tween 80.

Nutrient agar + 3% Tween 80.

Suspension of spores in tap water, from ampoule. hours at 35°C.

The spores were suspended in warm water 55°C, and aliquots of water were added to preweighed test material, (to make solution totally 100 g). Periodic agitation and recovery as in previous experiment. 3 J 3 3 - 21 Test material and control TME 2 (2%) TME 2 (1%) TME 2 (0.5%) Water 2% alkaline Glutaraldehyde Mean count I.F. survivors/ml 6.35 x 105 315,000 602,500 635,000 ,350 1.30 x 102 Note: S subtilis was chosen because in previous work by other workers it has proved particularly hardy with respect to glutaraldehyde.

Example 46 SPORICIDAL ACTIVITY OF TOSPEC TME 2 UNDER CONDITIONS OF HEAVY CONTAMINATION Test Material TOSPEC TME 2. Concentration 2% active aldehyde Contact time 2 hours and 3 hours. Temperature 2O°C. Test Organisms Mixed aerobic spores. Organic Material 25 g mixed vegetable detritus/100 g of test solutions. Inactivator Nutrient broth + 3% Tween 80. Recovery Medium Nutrient agar (Difco) + 3% Tween 80. Challenge Spores contained in above organic matter. Incubation 72 hours at 35°C. Control PROTOCOL (a) Water (b) 1% active chlorine, hypochlorite detergent.

Challenge was added to the test solutions (100 ml) with agitation. At the end of the contact time, duplicate aliquots (1 ml ) were serially diluted 1:100 in inactivator solution. Duplicate 1 ml samples were then added to Nutrient agar plus 3% Tween 80. Plates were then incubated. 4,3 4 3 - 22 RESULTS Test Material Mean count 2 hours- Survivors 3 hours TME 2 (2% active) 6.300 ZL 100 5 Hypochlorite (1% active) 68,000 55,000 Water 160,OOO 160,000 Example 47 CONTACT TIME OP TOSPEC TME 2 AGAINST BACILLUS SUBTILIS SPORES Test Procedure Sporicidal contact time. Test material TOSPEC TME 2 Concentration 2% active aldehyde. Temperature 20°C. Test Organism B subtilis spores. 15 Organism origin ATCC Organic material none.

Inactivator Recovery Medium Challenge Incubation Nutrient broth + 3% Tween 80.

Nutrient agar + 3% Tween 80. one ampoule of spore suspension containing 10θ spores/ml. hours at 35°C.

PROTOCOL a solution of the test material was prepared in 100 ml of tap water. The contents of an ampoule of spore suspension (bifco) were aseptically transferred to a test solution. At each contact time duplicate aliquots were serially diluted 1:100 in inactivator solution. Duplicate 1 ml samples were then transferred to the recovery medium for incubation. 45333 - 23 RESULTS Test material Contact time mean count Survivors ml.

TME 2 0 mins io8 TME 2 5 mins 700.000 TME 2 15 mins 6,750 TME 2 30 mins 450 TME 2 60 mins 0 Bacillus subtilis was chosen because in previous work by other workers it has consistently proved to be the most resistant bacterial spore with respect to treatment by chemical agents especially glutaraldehyde.

Example 48 BACTERICIDAL ACTIVITY TOSPEC TME 2 Test Procedure B.D.M.A./BS 3286 Test Material TOSPEC TME 2 2% active aldehyde Contact time 2 minutes Temperature 20°C Test of Organism As indicated Origin of Culture Leeds University Collection Inactivator Nutrient broth + 3% Tween 80 Recovery Medium Nutrient agar + 3% Tween 80. Double strength Letheen Broth Challenge 1 ml of nutrient broth culture incubated at 37°C for 24 hours Incubation 72 hours at 37°C S 4 3 3 RESULTS Solid recovery Liquid recovery Reinnoc of liq to check stasis S AUREUS . -- - _ _ _ + + + Str PYOGENES - — + + + D PNEUMONIAE - — + + + E COLI - — + + + Ps AERUGINOSA - — + + + Ps PLUORESCENS - — + + + P VULGARIS - — + + + K AEROGENES - — + + + B SUBTILIS - — + + + No Growth Growth + CONTROL COUNTS S AUREUS 6.5 X 107/ml E COLI 5.0 X 107/ml Ps AERUGINOSA 1.2 X 108/ml METHOD ml challenge to 9 ml TOSPEC TME 2, 2 minutes contact 20 time withdrawal of 1 ml test solution and add to 9 ml inactivator 2 minutes, transfer 1 ml in triplicate to 9 ml solid and liquid recovery media.

NOTE: Similar results were obtained using TOSPEC TME 2 at 1%, 0.5% and 0.05% active aldehyde.

Example 49 Preparation TME 5 and TME 10 were tested for their germicidal and sporicidal properties in accordance with the official sporicidal test adapted by the Association of Official Agricultural Chemists (A.O.A.C. 1961).

Briefly, this test comprises exposing porcelain cylinders carrying bacteria or bacterial spores to the test 48138 - 25 solution for different periods of time at a temperature of 20°C and then transferring the cylinders to a subculture medium known to support the growth of such micro-organisms..

The cultures (including controls) are incubated at 37°C for 1 week or 2 weeks as the case may be. If no growth is observed in the subculture media after the 2-week period the solution is considered bactericidal or sporicidal (as the case may be).

The spores against which the preparations were tested were NCTC strains of Bacillus Olobigii. Bacillus subtilis. closttridium tetani and Clostridium welchii. Standard tests, known in the art, were conducted to rule out bacteriostasis or sporistasis.

Both preparations were found to kill Bacillus globigii, Bacillus subtilis. Clostridium tetani and Clostridium welchii organisms in a period of less than 3 hours.

Claims (6)

1. A solid composition suitable for use in making up a microbiocidal solution, or dispersion, which comprises (a) a saturated dialdehyde having from 2 to 6 carbon 5 atoms absorbed and/or adsorbed on an inorganic or organic carrier material or on a mixture of two or more such carrier materials, and (b) an alkalinating agent or agent capable of yielding an alkalinating agent on admixture with a solvent for the 10 dialdehyde, the or each carrier material being capable of adsorbing and/or absorbing the dialdehyde to give a substantially dry freeflowing particulate material that on subsequent admixture with a solvent for the dialdehyde substantially releases the 15 dialdehyde.

2. A composition as claimed in claim 1, wherein the aldehyde is glutaraldehyde.

3. A composition as claimed in claim 1, wherein the aldehyde is malonaldehyde, succinaldehyde, adipaldehyde, or 20 glyoxal.

4. A composition as claimed in any one of claims 1 to 3, wherein the carrier material is a natural or synthetic polysaccharide or a cellulose derivative.

5. A composition as claimed in any one of claims 1 to 25 3, wherein the carrier material is an inorganic substance which falls into one or both of the following categories: (i) the anhydrous salts and those salts possessing higher or lower levels of hydration and that are capable of taking up water, and 30 (ii) the adsorbent and/or absorbent minerals, both 27 e3433 natural and synthetic, or is a mixture of two or more thereof. 6. A composition as claimed in claim 5, wherein the carrier is sodium sulphate or potassium sulphate. 7. A composition as claimed in claim 5, wherein the carrier is a form of silica. 8. A composition as claimed in claim 7, wherein the carrier is diatomaceous earth or precipitated silica. 9. A composition as claimed in claim 7, wherein the carrier is fumed silica or a sol- or gel-forming grade of synthetic heetorite. 10. A composition as claimed in claim 9, wherein the carrier is a synthetic heetorite which comprises a peptiser. 11. A composition as claimed in claim 10, wherein the peptiser is tetrasodium pyrophosphate. 12. A composition as claimed in claim 7, wherein the carrier is heetorite, bentonite, attapulgite, a montmorillonite clay or Fuller's earth. 13. A composition as claimed in claim 5, wherein the carrier is talc, chalk, kaolin, china clay or whitings. 14. A composition as claimed in any one of claims 1 to 13, wherein the alkalinating agent is an alkali metal carbonate, bicarbonate or phosphate, or a mixture of two or more thereof. 15. A composition as claimed in claim 14, wherein the alkalinating agent is sodium bicarbonate or tetrasodium pyr oph os phate. 16. A composition as claimed in any one of claims 1 to 15, wherein the alkalinating agent is encapsulated or - 28 coated. 17. A composition as claimed in claim 16, wherein the alkalinating agent is microencapsulated. 18. A composition as claimed in claim 16 or claim 17, 5 wherein the encapsulating or coating material is watersoluble . 19. A composition as claimed in claim 18, wherein the encapsulating or coating material is selected from the group consisting of gelatin and cross-linked gelatin, emulsified IO. fats, hardened tallow, calcium alginate (in the presence of sodium ions), polyvinyl pyrrolidone and polyvinyl alcohol. 20. A composition as claimed in any one of claims 1 to 3, 5, 7, 8, 9 and 12, wherein the alkalinating agent comprises an internal alkalinating agent, as hereinbefore 15 defined, and an external alkalinating agent, as hereinbefore defined. 21. A composition as claimed in any one of claims 1 to 20, which also comprises one or more substances inert to the dialdehyde and selected from anionic, cationic, non-ionic and 20 amphoteric surfactants, corrosion inhibitors, defoaming agents, chelating agents, dyes and perfumes, and other biocidal substances. 22. A composition as claimed in claim 1, substantially as described in any one of Examples 1 to 3 and 9 to 23. 25 23. A solid composition suitable for use in making up a microbiocidal solution, which comprises a saturated dialdehyde having from 2 to 6 carbon atoms adsorbed and/or absorbed on an inorganic or organic carrier material or on a mixture of two or more such carrier materials, the or each 30 carrier material being capable of adsorbing and/or absorbing 4 3 3 - 29 -the dialdehyde to give a substantially dry free-flowing particulate material that on subsequent admixture with a solvent for the dialdehyde substantially releases the dialdehyde. 24. A composition as claimed in claim 23, wherein the, each or a carrier material is capable of functioning as an alkalinating age;.t and/or incorporates an alkalinating agent. 25. A composition as claimed in claim 24, wherein the carrier is a synthetic hectorite which comprises a peptiser. 26. A composition as claimed in claim 25, wherein the peptiser is tetrasodium pyrophosphate 27. A composition as claimed in claim 23, wherein the carrier is as defined in any one of claims 4 to 9, 12 and 13. 28. A composition as claimed in any one of claims 23 to 27, which also comprises one or more substances as defined in claim 21. 29. A composition as claimed in claim 23, substantially as described in any one of Examples 4 to 6. 30. A composition as claimed in claim 24, substantially as described in Example 7 or Example 8. 31. A composition as claimed in any one of claims 1 to 30 in unit dosage form. 32. A process for the production of a composition as claimed in claim 1, which comprises admixing the carrier material and the dialdehyde and then admixing the alkalinating agent. 33. A process as claimed in claim 32, wherein the dialdehyde is sprayed on to the carrier material. 45433 - 30 34. ' A process as claimed in claim 32, carried out' substantially as described in any one cf Examples 1 to 3 9 to 23 herein. 35. A composition as claimed in claim 1, whenever 5 prepared by a process as claimed in any one of claims 32, 34. , ; 36. A process for the production of a composition and to as claimed in claim 23, which comprises admixing the carrier material a'nd the dialdehyde. 10 37. A process as claimed in claim 35, carried out substantially as described in any one of Examples 4 to 8 herein. 38. A composition as claimed in claim 23, whenever prepared by a process as claimed in claim 35 or claim 37. 15 39. A two-pack system which comprises a pack comprising a composition as claimed in any one of claims 23 to 31 together with a pack comprising one or more alkalinating agent(s). 40. A two-pack system as claimed in claim 39, wherein the composition and the alkalinating agent are in unit dos20 age form. 41. A liquid or gel biocidal preparation which comprises a composition as claimed in any one of claims 1 to 22, a composition as claimed in any one of claims 23 to 31 and an alkalinating agent, where appropriate, or the two compo25 nents or a two-pack system as claimed in claim 39 or claim 40, in admixture with a dialdehyde solvent. 42. A preparation as claimed in claim 41, wherein the dialdehyde solvent is water. 43. A preparation as claimed in claim 41 or claim 42, 30 which comprises up to 5% of active dialdehyde. Λ5438 - 31 44. A preparation as claimed in claim 43, which comprises up to 2% of active dialdehyde. 45. A preparation as claimed in claim 44, which comprises up to 0.5% of active dialdehyde. 46. A preparation as claimed in claim 45, which comprises from 0.05 to 0.25% of active dialdehyde. 47. A method of disinfecting or sterilising an article or surface infected by microorganisms or liable to infection by micro-organisee, which comprises applying to the article or surface a preparation as claimed in any one of claims 41 to 46. 48. A method of disinfecting or sterilising a domestic article or surface infected by micro-organisms or liable to infection by micro-organisms, which comprises applying to the article or surface a preparation as claimed in any one of claims 41 to 46. 49. A method of disinfecting or sterilising a surface in a hospital or surgery infected by micro-organisms or liable to infection by micro-organisms, or non-surgieal or medical apparatus or equipment infected by micro-organisms or liable to infection by micro-organisms, in a hospital or surgery, which comprises applying to the surface, apparatus of equipment a preparation as claimed in any one of claims 41 to 46. 50. A method of sterilising surgical and medical instruments, equipment and apparatus infected by microorganisms or liable to infection by micro-organisms, which comprises applying to the instrument, equipment or apparatus a preparation as claimed in claim 44 or claim 45. 51. A method of sterilising dental instruments, equipment and apparatus infected by micro-organisms or liable to -32 infection by micro-organisms, which-comprises applying to the instrument, equipment or apparatus a preparation as claimed in claim 44 or claim 45. 52. A method of disinfecting or sterilising a surface 5 or plant infected by micro-organisms or liable to infection by micro-organisms, in premises of the food, dairy, brewing or pharmaceutical industry, which comprises applying to the surface or plant a preparation as claimed in any one of claims 41 to 46. 10 53. A method of disinfecting or sterilising soil, which comprises applying to the soil a preparation as claimed in any one of claims 41 to 46. 54. A method as claimed in claim 53, wherein the preparation also comprises a nematocide. 15 55. A method of treating a crop area and/or an adjacent area to prevent and/or combat infection by micro-organisms, which comprises applying to the crop area and/or adjacent area a preparation as claimed in any one of claims 41 to 46. 56. A method as claimed in claim 55, wherein the 20 preparation also comprises an insecticide. 57. A method of treating seeds or post-harvest crops to prevent and/or 'combat infection by micro-organisms, which comprises applying to the seeds or crop a preparation as claimed in any one of claims 41 to 46. 25 58. A method of disinfecting or sterilising farm buildings and plant infected by micro-organisms or liable to infection by micro-organisms, which comprises applying to the building or plant a preparation as claimed in any one of claims 41 to 46. 30 59. A method of treating an animal to prevent and/or Αΰ 4 3 3 - 33 combat topical infection with micro-organisms, which comprises applying to the animal a preparation as claimed in any one of claims 41 to 46. 60. A method a3 claimed in claim 59, wherein the 5 preparation is sprayed into a poultry house containing poultry.

6. A met; od of disinfecting eggs, which comprises washing the eggs in a preparation as claimed in any one of claims 41 to 46. 10 62. A pharmaceutical preparation which comprises a preparation as claimed in any one of claims 41 to 46 in admixture or conjunction with a pharmaceutical suitable carrier.