WO2005092095A1

WO2005092095A1 - Bactericidal liquid skin composition

Info

Publication number: WO2005092095A1
Application number: PCT/IB2005/000738
Authority: WO
Inventors: Jacques Schram; Andre Schram; Charles Joubert Marais
Original assignee: Green World Chemicals Cc
Priority date: 2004-03-23
Filing date: 2005-03-22
Publication date: 2005-10-06

Abstract

The invention is a liquid skin composition having a sustained bactericidal effect which includes a lower alcohol, Triclosan, a surfactant and water as a carrier. The composition is applied and allowed to dry. No rinsing is required. The lower alcohol will be selected from C2 to C3 alcohols and preferably one or a combination of Propyl Alcohol, iso Propyl Alcohol and Ethanol. In a preferred embodiment, the surfactant is a combination of Sodium Lauryl Ether Sulphate and Coconut Diethanolamide. There is also provided for an aromatic compound to be included in the composition. A skinfriendly liquid composition for protection of external skin, in particular on the hands, which first eliminates and then inhibits bacterial growth to contain the transmission of disease through human contact is thus provided.

Description

BACTERICIDAL LIQUID SKIN COMPOSITION

FIELD OF THE INVENTION

The invention relates to a bactericidal liquid composition with a sustainable effect for cleaning and disinfecting skin, and in particular hands and arms.

BACKGROUND OF THE INVENTION

A number of disinfectants, antibacterial soaps, surgical or hygienic hand rubs, and other similar products have an immediate effect of killing germs on application. However, soon after they are applied the effect stops. No sustained protection is offered against subsequent contact with germs. It is well known that human contact is a predominant vehicle for the migration of germs, microbes, bacteria and viruses which result in the transmission of diseases.

In fact, most diseases can be transmitted through human contact and in particular through hand contact. Doctors and healthcare workers are exposed to sick people daily and unwillingly become a vehicle for the transmission of diseases. There are many other examples of how diseases are transmitted through human contact during daily activities. The problem is more prolific in rural areas where cleaning facilities and products are less readily available for people to wash their hands.

OBJECT OF THE INVENTION

It is an object of the current invention to provide a bactericidal liquid composition that will at least assist in the prevention of disease transmission through human contact.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided a liquid skin composition having a sustained bactericidal effect comprising water as a carrier, a lower alcohol, a surfactant and Triclosan.

The invention further provides for the surfactant to be selected from the group comprising Sodium Lauryl Ether Sulphate and Coconut Diethanolamide or a combination thereof.

Further features of the invention provide for the lower alcohol to be selected from the group comprising C2 to C3 alcohols; and for the alcohol to be selected from the group comprising Propyl Alcohol, iso Propyl Alcohol and Ethanol or combinations thereof.

Still further features of the invention provide for the composition to comprise the following in mass %: Propyl Alcohol 14 % to 70 %; Triclosan 0.2 % to 2 %; and Surfactant 3 % to 30 %.

Yet further features of the invention provide for the composition to comprise the following in mass %: Propyl Alcohol about 17 %; Triclosan about 0.3 %; Sodium Lauryl Ether Sulphate about 7 %; and Coconut Diethanolamide about 5 %.

Another feature of the invention provides for the composition to include an aromatic compound.

These and other features of the invention will now become apparent from the following description of the invention by way of example.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides a liquid bactericidal composition which includes a lower alcohol, Triclosan and a surfactant. The lower alcohol may be any suitable C2 or C3 alcohol. In particular, it has been found that Propyl Alcohol is suitably effective. However, the alcohol may be selected from Propyl Alcohol, iso Propyl Alcohol and Ethanol or combinations thereof. The surfactant in this embodiment is a combination of Sodium Lauryl Ether Sulphate (SLES) and Coconut Diethanolamide (CDE).

The mentioned ingredients may be present in the following mass % ranges:

Propyl Alcohol 14 % to 70 % Triclosan 0.2 % to 2 %

Surfactant 3 % to 30 %

At least the major part of the balance of the composition is made up of purified water as the carrier.

More specifically, this embodiment of the composition comprises the following ingredients in mass %: Propyl Alcohol about 17 %

Triclosan about 0.3 %

Sodium Lauryl Ether Sulphate about 7 % Coconut Diethanolamide about 5 %

Aromatic compound about 0.2 %

Water about 70.5 %

The Triclosan is in the form of that marketed by Ciba as IRGASAN^®DP 300. The aromatic compound may be in any suitable form.

The ingredients of the composition serve the following purposes:

1. The Propyl Alcohol provides the substantially immediate kill of bacteria. 2. The Triclosan provides the long-lasting antibacterial effect. 3. The at least one surfactant lowers the surface tension between the composition constituents which also has the effect of cleaning the skin and furthermore facilitates sustainability of bactericidal effect of the product.

The specific surfactants mentioned, Sodium Lauryl Ether Sulphate and Coconut Diethanolamide, are respectively anionic and non-ionic surfactants. These compounds also to a degree serve the purpose of a carrier for the Triclosan.

On application the composition kills bacteria, germs, and other disease transmitting organisms to a desirable degree within 1 minute. This is approximately the time required for the hands to dry, and then any other such organisms that come into contact with the covered and protected area of the skin are inhibited against growth. The drying time obviously depends on the amount of composition use and its alcohol concentration.

After the composition has dried, with the water and alcohol evaporated, the surfactant remains on the skin and serves to keep the Triclosan in contact therewith. The result is that, contrary to other surgical rubs, hand rubs, hand soaps, and other similar products which wash off when rinsing ones hands after having killed the bacteria thereon, the Triclosan remains on the skin and protects it and inhibits bacterial growth.

A rinse of the skin, subsequent to drying of the composition, will remove the surfactant to some degree, but the Triclosan will remain to give the extended bactericidal effect.

The fact that the composition is applied to the skin and allowed to dry without requiring water to rinse makes it very useful in many fields and specifically in rural areas where there is a shortage of cleaning facilities and products. The composition, because of its formulation, is also skin-friendly which is highly desirable. The surfactant also moisturises the skin providing a softening effect and protects the skin against the Propyl Alcohol which can otherwise cause irritation or dry the skin out.

The invention thus provides a composition for the protection of external skin, in particular on the hands, to first eliminate and then inhibit bacterial growth on treated skin and in so doing contain the transmission of disease through human contact.

The composition kills bacteria substantially immediately and inhibits the growth of bacteria for up to 5 or 6 hours after application. It is applied to and allowed to dry on the skin without rinsing.

The inhibition is present even after extensive washings after application and represents satisfactory long-lasting antimicrobial and bactericidal efficacy. It will be appreciated that this sustainability on the skin facilitates the prevention of the transmission of diseases from one person to another.

It will be appreciated that different surfactants will facilitate the mentioned sustainability to the composition to a different degree, and will also vary in effectiveness as a carrier. The bactericidal efficacy of the composition on hands has been tested as follows:

The antibacterial effects of the liquid composition with Triclosan in the form of IIRRGGAASSAANN^®®DDPP 330000 wweerree ddeetteerrmmiinneedd.. TThhiiss wwaass ddoonnee uunnddeerr in-v/vo finger print test conditions against gram-positive and gram-negative bacteria.

The following germs were selected for the tests: Staphylococcus aureus as the pathogenic gram-positive bacteria and Escherichia coli as the gram-negative bacteria.

The bactericidal efficacy of the composition was tested under suspension test conditions according to the European Standard EN 12054.

Finger print test: (This was conducted in terms of the Ciba Specialty Chemicals Method No. 177e)

In vivo test for determination of the bacteriostatic activity of a product that contains an antimicrobial agent.

Test bacteria: Staphylococcus aureus ATCC 9144 Escherichia coli NCTC 8196

Nutrient medium: Casein soy meal peptone agar Incubation: 24 hours at 37°C

Principle:

1. The hands were wetted for 15 sec. under running tap water.

2. Hands were washed with placebo soap, rinsed with tap water and dried.

3. Filter paper discs (2 cm diameter) soaked with ethanol were placed in sterile plates. The fingertips were applied on the filter paper discs for 30 sec. in order to allow a migration of the antimicrobial due to the excellent adsorption of ethanol. After 1 minute contact time, the filter discs were dried in the plates and then placed in the middle of agar plates containing the test germs (placebo sample).

4. 3ml of the composition was rubbed on the hands. 5 minutes after application the composition was rinsed for 30 seconds and the anti-bacterial efficacy was measured.

5. Ethanol soaked filter paper disks (2 cm diameter) were placed in sterile plates and the same procedure as described under 3. was performed.

6. The procedure described in 5. was repeated 2 and 4 hours after application of the test product in order to determine the long lasting activity of antimicrobial on the skin.

7. The plates were incubated under optimal conditions according to the germ's requirements on temperature and media (see above).

8. Due to the diffusion of the antimicrobial ingredient from the filter into the surrounding agar medium the growth of the test germs is inhibited in the diffusion zone.

For the assessment of the bacteriostatic activity, zones of inhibition around the filter discs are measured and given in mm.

Results:

Each test was performed twice and both results are given in the table. Zl = Zone of Inhibition in mm Vr = Vinson rating 0 = strong growth (no activity) 4 = no growth (very good activity)

Determination of the microbiocidal activity according to the suspension test method EN 12054 (membrane filtration method):

Sample: Composition with IRGASAN^®DP 300

Test organisms: Staphylococcus aureus ATCC 6538 Enterococcus hirae ATCC 10541 Escherichia coli NCTC 10538 Pseudomonas aeruginosa ATCC 15442

Test concentration 90% Contact time: 1 and 5 minutes Requirements: At least 3 log reduction after 1 minute contact time in case of hygienic hand wash and after 3-5 minutes contact time in case of surgical hand wash. Inactivating medium for dilution: NaCI-Peptone + 3% Tween 80 + 0.3% lecithin + 0.1 % histidine + 0.5% Na-Thiosulfate(TLHNa) Nutrient medium: Tryptic-soya-agar, (TSA) Incubation of plates: 24-48 hours at 37°C Preparation of the inoculums: Before using the bacteria culture for the suspension test, three consecutive daily transfers were made on Tryptic soy agar slants and incubated at 37°C, then washed with tryptone-water and diluted up to a content of 1.5 - 5.0 x 10⁸ cfu/ml.

Principle of the method:

1. 1 ml of a bacterial suspension was added to 9 ml of formulation and mixed thoroughly. After the prescribed exposure time of 5 minutes at 21 °C +/- 1 °C aliquots of 0.1 ml of the test mixture were taken and added to 50 ml of TLHNa combination (= Test neutralization mixture, TNM 10°.) Dilutions of the Test neutralization mixture(TNM) were prepared by pipetting 500 μl of TNM to 9 ml of TSB + inactivation combination (dilutionlO^"2 ) or 50 μl of TNM to 9 ml TSB + inactivation (dilutionlO^-3 ).

2. The TNM and each of the dilutions were transferred to a membrane filter device fitted with a membrane filter and filtered immediately. 3. Subsequently the filters were washed with 150 ml of distilled water. The membranes were transferred to TSA and incubated for 48 h at 37°C. 4. After incubation the colonies were counted and reported as log reduction in a table.

Verification of methodology:

For each bacterial suspension it was checked that -

1. The bacterial suspension was between 1.5- 5x10⁸cfu/ml.

2. The diluted bacterial suspension was between 6x10²-3x10³ cfu/ml.

3. The validation of inactivation of filtration process was in the normal range.

Results:

Bactericidal activity according to EN 12054 in log bacteria reduction / contact time 1 and 5 minutes

Conclusion based on the tests:

The composition of the current invention shows satisfactory long-lasting antibacterial efficacy against gram-positive and gram-negative bacteria. The hands are thus protected from growth of bacteria even after subsequent rinsing.

In addition the composition shows strong bactericidal efficacy and fulfills the European requirements (EN12054) for products used for both surgical and hygienic hand rubs. This bactericidal efficacy protects treated skin from bacterial growth for hours after the composition has been applied. It will be appreciated by a person skilled in the art that the composition may be varied from the embodiment set out above without departing from the scope of the current invention. Alternative suitable surfactants will be apparent to a suitably skilled person.

Claims

1. A liquid skin composition having a sustained bactericidal effect comprising water as a carrier, a lower alcohol, a surfactant and Triclosan.

2. A composition as claimed in claim 1 in which the surfactant is selected from the group comprising Sodium Lauryl Ether Sulphate and Coconut Diethanolamide or a combination thereof.

3. A composition as claimed in claim 1 or claim 2 in which the lower alcohol is selected from the group comprising C2 to C3 alcohols.

4. A composition as claimed in claim 3 in which the alcohol is selected from the group comprising Propyl Alcohol, iso Propyl Alcohol and Ethanol or combinations thereof.

A composition as claimed in claim 4 which comprises the following in mass %: Propyl Alcohol 14 % to 70 %; Triclosan 0.2 % to 2 %; and Surfactant 3 % to 30 %.

6. A composition as claimed in claim 5 which comprises the following in mass %: Propyl Alcohol about 17 %; Triclosan about 0.3 %; Sodium Lauryl Ether Sulphate about 7 %; and Coconut Diethanolamide about 5 %.

7. A composition as claimed in any of the preceding claims which includes an aromatic compound.

8. A composition as claimed in any of the preceding claims in which the Triclosan is IRGASAN^®DP 300.