WO1991012721A1

WO1991012721A1 - Disinfectant

Info

Publication number: WO1991012721A1
Application number: PCT/GB1991/000240
Authority: WO
Inventors: Bernard Patrick Bradley
Original assignee: Hill, Kenneth, John
Priority date: 1990-02-20
Filing date: 1991-02-18
Publication date: 1991-09-05
Also published as: ZA907620B; GB9003787D0

Abstract

A bacteriocidal and viricidal disinfectant composition suitable for application to the skin comprises (a) 2.3 to 4.0 wt % 2-phenoxyethanol; (b) 0.8 to 1.8 wt % complexed iodine; (c) 5.0 to 20.0 wt % anionic or amphoteric surfactant; (d) 1.5 to 6.0 wt % vegetable oil diethanolamide; the balance being water; and the pH of the composition being less than 6.5. Preferably, it is in the form of a viscous skin cream containing suitable emollients.

Description

DISINFECTANT

The present invention relates to a bacteriocidal and viricidal disinfectant composition suitable for application to the skin and particularly but not exclusively, for use in hospitals as a pre-operative scrub or for use in emergency situations.

Disinfectant compositions have been known for many years and their principal objective has been the killing of bacteria. The disinfectant products used at present in industry are generally selected on the basis of their bacteriocidal properties. However, these products are sometimes inadequate to deal with viruses, which may be more difficult to kill effectively. More recently, a number of pathological viruses have evolved, the most notable being the human immunodefficiency virus (HIV) which is responsible for acquired immunodefficiency syndrome (AIDS) . ϊ- ere is the potential for such viruses to be transmitted by skin contact, and there is a danger of infection where open wounds are present. For example, a policeman or ambulanceman who sustains an open wound in dealing with a drug addict or other person having a high probability of HIV infection, requires a quick and convenient disinfectant composition which can be used immediately.

Similarly, there is a need in hospitals for a pre-operative scrub for surgeons and nurses which has maximum efficiency in killing viruses and bacteria, but which is topically acceptable so that the hands do not become sore with repeated use.

Compositions comprising 2-phenox ethanol and complexed iodine as active agents are known in the prior art. However, a number of such formulations have been found to stain the skin, which is generally undesirable, particularly where the composition is to be used repeatedly as, for example, a pre-operative scrub.

Finally, since the disinfectant composition may require to be used in emergency situations where the skin or wound is dirty, it is desirable that the disinfectant composition should include a surfactant, so that it is capable of cleaning and disinfecting in one operation.

It is therefore an object of the present invention to provide a bacteriocidal and viricidal disinfectant composition suitable for application to the skin which additionally incorporates a surfactant for cleansing.

The present invention provides a bacteriocidal and viricidal disinfectant composition suitable for application to the skin, which comprises

(a) 2.3 to 4.0 (preferably 2.3 to 3.5) weight % 2-phenoxyethanol

(b) 0.8 to 1.8 (preferably 1.0 to 1.8) weight % complexed iodine

(c) 5.0 to 20.0 weight % anionic or amphoteric surfactant

(d) 1.5 to 6.0 (preferably 1.5^'to 3.0) weight % vegetable oil diethanolamide; the balance being water; and the pH of the composition being less than 6.5.

The present disinfectant composition is bacteriocidally effective against gram positive and gram negative bacteria. It will also kill viruses such as HIV and Herpes Simplex on the surface of the skin.

■ A number of complexed iodine formulations are known in the art, such as polyvinylpyrrolidone-iodine complexes and other iodophors. The present invention envisages the use of any of these in appropriate proportions. The iodine complex generally imparts a brown colour to the disinfectant composition, which allows the areas of the skin being cleansed by the composition to be monitored visually so as to ensure complete coverage. Despite this brown colouration, the composition has been found to be non-staining - possibly due to the presence of the surfactant.

The surfactant is one which is compatable with the active disinfecting agents and imparts cleansing properties to the composition. The anionic surfactant is generally a long chain sulphate or sulphonate, including alcohol sulphates, and commercially available surfactants generally include a mixture of such compounds. The surfactant might also be an amphoteric surfactant, such as CoCo amido betaine which can exist in either anionic or cationic forms depending on pH. The vegetable oil diethanolamide may be based on any of the available natural oils, such as coconut oil. The function is to provide a surfactant and emolient, which renders the composition viscous and compatible with the skin. Preferably, the disinfectant composition is provided in the form of a skin cream which is applied undiluted and may be washed off after use. This facilitates use in.emergency situations. Generally the viscosity is in the range 180-275 cS as determined on a Brookfield viscometer.

The pH of the composition is less than 6.5, preferably in the range 5.5 to 6.0 or as low as 2.5 to 3.0. The active disinfectant agents are only effective under acid conditions, although the use of very acidic compositions is to be avoided as causing skin damage.

The composition may also contain additional emolients, such as glycerine or lanolin, usually in an amount 1.0 to 2.0 weight %. Glycerine is to be preferred since it is substantially non-allergenic.

Additionally, the composition may include formulation adjuncts necessary to provide a stable and partially clarified composition, such as isopropyl alcohol. This prevents phase separation, clarifies the composition to a degree, and additionally acts as a germicide in its own right.

As mentioned above, the composition is. preferably in the form of a skin cream which is conveniently used undiluted. The composition may be provided in multidose containers equipped with dispensing means, or may be provided in discreet dosage packages such as sachets, usually containing 2-10ml, preferably 3-5ml.

The effective viricidal properties of the disinfectant composition make it particularly useful in emergency situations where HIV virus may be encountered and also provide a pre-operative scrub which is generally more effective than those used at present (such as those based on parachloro etaxylenols) . The composition also finds general use in hospitals for routine hand disinfectant by doctors and nurses to avoid transmission of micro-organisms, which can survive for prolonged periods on the skin. In the food industry, many instances of food poisoning could be prevented by careful hand disinfection. It is generally recognised that hygenic hand washing in the xoodstuff industry is a major factor in controlling the spread of harmful bacteria. In the cosmetics and pharmaceuticals industry, the prevention of contamination by bacteria from human sources is an integral part of good manufacturing practise in the production and processing of toiletries, cosmetics and pharmaceuticals.

Embodiments of the present invention will now be described by way of example only. Example 1 (Anionic Surfactant)

A disinfectant composition according to the invention was made up from the following:

2.5 weight % 2-phenoxyethanol

1.2 weight % iodine - polyvinylpyrrolidone complex

30.0 weight % lauryl ether sulphate (3 mole)

(27% pure = 8.1% active).

1.5 weight* % glycerine B.P. - ~

1.5 weight % coconut oil diethanolamide

2.0 weight % isopropyl alcohol

61.3 weight % water total volume equals 1,000 ml.

500ml of water were placed in a mixing vessel and heated to 60°C. The lauryl ether sulphate was mixed with the coconut oil diethanolamide and the mixture heated to 60°C, before being added to the water and cooled to 20°C. The pH was adjusted to 2.5 - 3 using 50% citric acid solution. The glycerine and isopropyl alcohol were mixed together before being added to the previous mixture. Mixing was carried out for 10 minutes before addition of the 2-phenoxyethanol and the iodine. Further mixing was carried out for one hour and the balance of the water added to bring the volume up to 1,000ml.

Example 2 (Amphoteric Surfactant)

A further disinfectant composition according to the invention was made up as follows: (3.8 wt%) 2-phenoxyethanol

(1% available iodine) iodine - polyvinylpyrrolidone complex. 50 1 (16 wt%) CoCo amido betaine

(60% active solution) 10 1 (5 wt%) coconut oil diethanolamide 1.6 1 (0.8 wt%) citric acid (50% solution) 120 1 (balance) water total volume equals 200 litres

Half of the volume of water was placed in a vessel and the iodine-polyvinylpyrrolidene complex was added under high shear conditions and mixing was effected for one hour. The 2-phenoxyethanol was then added and further mixing carried out for 30 mins.

In a separate vessel, the CoCo-a ido betaine was mixed with the coconut oil diethanolamide and the remainder of the water, and mixed for one hour. The pH of the second mixture was adjusted to pH 2.5 to 3.0 with the citric acid. The two mixtures were then mixed together and mixing continued for one hour. The product is useful as a surgical scrub.

The amphoteric surfactant CoCo-amido betaine is available from Sandor Chemicals, Leeds, UK under the tradename SANDOTERIC SC. the iodine-polyvinylpyrrolidone complex is available from BASF. Example 3 - viricidal Activity

The composition prepared in Example 1 was tested for viricidal activity as follows.

The disinfectant (used neat) inactivated 1 ml of HIV mixture which had been put on the shaved surface of rodent skin (5 x 5 cm²) at both 0.5 and 1 min contact times at 20°C. No residual virus infectivity was recovered by washing the outer surface of the skin with 5 ml of tissue culture medium and assaying for infectivity.

The disinfectant(used neat) (i.e. final concentration 1/2) inactivated 10⁸ pfu/ml of Herpes Simplex virus at both 0.5 and 1 min contact times at 20°C when residual infectivity was titrated in human fibroblast cells (MRC-5 cells). For this test series, at the end of the contact times the HSV in 90% serum was diluted in 10-fold steps to 10"⁶ and aliquots of each dilution were then plated onto monolayers of MRC-5 cells. After 3 days culture at 37°C the end point dilution of the HSV infectivity was read. The results show removal of viral infectivity.

Example 4 (Bacteriocidal Action)

The killing capabilities of the composition of Example 1 was assessed against a variety of micro-organisms. To simulate conditions of use where body fluids would provide Organic matter⁷ likely to inhibit product activity, a series of tests were conducted in the presence of serum at body temperature. In each case the concentration of organisms killed in the test suspensions was between 1 and 5 million per ml. These tests were performed at 37°C. The results are given in Table 1.

Table 1 Germicidal effect in the presence of 10% serum at 7°-C. Contact Time 1 minute

E. coli NCTC 10418 5.63% v/v

Staph. aureus NCTC 6571 5.63% v/v

Pseudomonas aeruginosa MUCOB 237 11.25% v/v Acinetobacter calcoaceticus 73099 5.63% v/v Salmonella paratyphi B MUCOB 211 2.82% v/v Klebsiella edwardsii var atlantae 2.82% v/v Proteus vulgaris MUCOB 364 2.82% v/v The tests we have performed show that the disinfectant is a highly active germicide even in the presence of relatively high concentrations of serum (10%) . The most resistant organism in these tests was Pseudomonas aeruσinosa which is a common finding where anti-bacterial tests are undertaken with antiseptics and disinfectants. However, this formulation still has a 9-fold higher concentration of available iodine than is required to kill a million Pseudomonas per ml in the presence of 10% serum at 37°C. The excess concentration is 18-fold greater than required for the strains of E-coli. Staph aureus and Acinetobacter calcoaceticus. The figures are significant in view of the fact that these organisms are serious hospital pathogens and Acinetobacter is a very troublesome pathogen in burns units, the strains currently carrying resistance to a wide range of antibiotics in common use and present great difficulties of eradication. The disinfectant would clearly be able to play a useful role in the prevention of sepsis, and the subsequent morbidity and deaths which result from infection with organisms listed above.

In these tests, the disinfectant composition was found to be substantially non-staining, possibly due to the presence of the surfactant.

Example 5 - Skin Compatibility

Skin compatibility tests were carried out by applying the composition to 5 cm² areas of skin on 30 patients at The Royal Infirmary, Glasgow. The patients were those suffering from a variety of skin complaints. No patient showed any allergic reaction to the composition of the invention. Two (only) of the patients reported a slight staining effect.

Claims

CIAIMS

1) A bacteriocidal and viricidal disinfectant composition suitable for application to the skin which comprises

(a) 2.3 to 4.0 wt % 2-phenoxyethanol;

(b) 0.8 to 1.8 wt % complexed iodine;

(c) 5.0 to 20.0 wt % anionic or amphoteric surfactant;

(d) 1.5 to 6.0 wt % vegetable oil diethanolamide; the balance being water; and the pH of the composition being less than 6.5.

2) A composition according to claim 1 having an elevated viscosity such that the composition is suitable for use as a skin cream.

3) A composition according to claim 2 wherein the viscosity is in the region 180-275 cS.

4) A composition according to claim 1 which further comprises glycerine.

5) A composition according to claim 1 which further comprises isopropyl alcohol.

6) A composition according to claim 1 having a pH of 5.5 to 6.0. 7) A composition according to claim 1 which comprises 2.3 to 4.0 wt % 2-phenoxyethanol.

8) A composition according to claim 1 wherein the surfactant is an anionic surfactant.

9) A composition according to claim 1 wherein the surfactant is an amphoteric surfactant.

10) A composition according to claim 1 comprising 1.5 to 3.0 wt % vegetable oil diethanolamide.

11) A composition according to claim 1 comprising 1.0 to 1.8 wt % complexed iodine.