Antimicrobial composition containing aluminium acetotartrate and a diol.
The present invention refers to a antimicrobial composition intended to reduce skin irritations especially under napkins.
Skin irritations under napkins are often a big problem. The problem occur e.g. during diarrhoea periods, with children and adults having eczema or other skin diseases or if the napkins are not changed often enough. The problems are often impaired by infections of different microorganisms. In order to prevent these problems it is important on one hand to reduce the effect of skin irritations caused by degradation products from urine and faecal, and on the other hand to inhibit the growth of fungi and bacteria.
In GB-A-1.024.193 there is described compositions with double salts of aluminium propionate and aluminium subpropionate, i.a. for treating infantile diaper rash. This composition is stated to inhibit enzymatic cleavage of urea to ammonia. There is no state¬ ment about any antimicrobial effect.
In SE-B-432 438 there is described a skin cleaning composition containing one or more synthetic tensides and to which aluminium acetotartrate is added in order to inhibit irritations and skin problems. Admixture of some other substances such as propylene glycol or glycerol is also mentioned, but not for what purpose and it is assumed that these substances are intended as solvents.
In SE-A-8305839-6 there is disclosed a skin treating preparation in the form of a lotion or balsam and in which 0,4 - 2% alsol (aluminium acetotartrate) is included as an adstringent, protec¬ ting and restorative component.
The purpose and most important feature of the invention
The object of the present invention is to provide a composition having an antimicrobial effect and which besides inhibits and prevents skin irritations especially under napkins. This has been
provided through use of a composition containing aluminium acetotartrate and at least one diol with antimicrobial proper¬ ties, said composition being in a solution, preferably aqueous solution.
Description of the invention
A mixture of 1% aluminium acetotartrate and 20% propylene glycol in water has been tested, concerning possible skin irritations and effect on different fungi and bacteria. Aluminium acetotart¬ rate is used in treatment of discharging skin diseases. The solution has a draining and cooling effect. The solution is acid which reduces the effect of tissue-injurious enzymes in faecal and urine.
Propylene glycol has known antimicrobial properties. Previous examinations have proved that it effectively inhibits the growth of many different bacteria and fungi in concentrations of 5-15%.
By mixing aluminium acetotartrate and propylene glycol in aqueous solution there is provieded a mixture having both a draining and cooling effect and an effective inhibition of the growth of many microorganisms. The components form a stable aqueous solution. As far as known to the applicants it is not previously known to combine these components in a stable aqueous solution. Besides aluminium acetotartrate has a pH-stabilizing effect on the solutio .
Propylene glycol can be present in the solution at a concentra- tion of 5-40% by weight, at which 10-30% by weight is a preferred interval. Aluminium acetotartrate can be present at a concentration of 0,1-50% by weight, at which 0,25-15% by weight is a preferred interval.
Tests have been performed with a water solution of:
- 1% aluminium acetotartrate
- 1% aluminium acetotartrate and 1% Nacl
- 1% aluminium acetotartrate and 10% propylene glycol
- 1% aluminium acetotartrate and 20% propylene glycol
Skin irritation test
A napkin wetted with 50 ml of one of these mixtures applied o the under side of the forearm on 2 volunteers during 24 hours. N skin irritations accurred for any of the mixtures.
Effect on microorganisms
The killing effect of these mixtures in vitro (in the laboratory against Staphylococcus aureus, S. epidermidis, Streptococcu faecalis, Escherichia coli and Candida albicans was examined. Th mixtures were incorporated in a solid test medium in the concen trations 12,25 and 40%. The test medium was DST (Oxoid, England) The killing effect was read as the lowest concentration (MIC) a which there was a total inhibition of the growth of the micro organism. The results can be seen in Table 1. In many cases w saw an inhibition of the growth of the microorganism with the 40 - mixtures, but no total killing except for the cases that ar seen from Table 1.
Below three experiments performed on two volunteers will b described. 1. The aluminiumacetotartrate - propane-l,2-diol solution wa applied on the volar aspect of the arm (5 x 5 cm). Candid albicans (104 cells ml~l, 0.2 ml) was applied on the test area. piece of diaper (5 x 5 cm) containing 8 ml of urine was applie on the test area. The diaper was covered with plast adhesive fo 8 hrs.
2. A solution containing C^_ albicans (104 cells ml ~1) wa applied on a 5 x 5 cm area on the volar aspect of the arm. Th area was covered with a piece of diaper (5 x 5 cm) containing mixture of urine and 25% of the test solution for 8hrs (8 ml).
3. A solution containing C_ albicans (104 cells ml~l) was applie on a 5 x 5 cm area on the volar aspect of the arm. The area wa
covered with a 5 x 5 cm piece of diaper containing 8 ml of urine for 8 hrs.
RESULTS: The results are in Table 2. A 10 fold reduction in the amount of C^ albicans was seen with both of the methods tested. The solution is fungistatic and not fungicidic. No growth of microorganisms will occur when the solution is applied on the skin before the diaper containting urine is placed on the area. The same is seen when the solution is applied on the diaper.
Table 1. The killing effect of different aluminium acetotartrate mixtures on different microorganisms.
C. albicans S.aureus S.epiderm. St. faecal E.c 1% alumin.ac. > 40% > 40% > 40% > 40 % 40%
1%
1% Nacl > 40% > 40% > 40% > 40% 40%
1% alumin.ac.
10% prop.glyc. > 40% > 40% > 40% > 40% 40%
1% alumin.ac.
20% prop.glyc. 40% 40% 40% 40% 25%
a: 40% means that there in the test medium is 40% of the exami and 60% medium.
Table 2. The fungistatic effect of a solution containing 1% aluminiumacetotartrate and 20% propane-1, 2-diol on Candida albicans in vivo.
vol no method control 1 3
1 6.8 x 103 6.0 x 10^ 5.9 x 104
3.0 x 103 2.0 x 10 4.2 x 104
Application
The mixture of 1% aluminium acetotartrate and 20% propylene glycol can preferably be applied on the napkin in the form of a spray. The solution is evenly applied on the napkin before this is applied to the skin. Altematievely the composition can be applied directly on the skin. It is also possible that the napki at the manufacturer is provided with a layer impregnated with the composition, at which the solvent has been allowed to evaporate. The layer is preferably arranged inside the surface layer of th napkin.
The killing effect on microorganisms is potentiated by the combination porpylene glycol and aluminium acetotartrate. It is as far as we known not previously known that aluminium acetotart¬ rate can have a certain inhibitory effect on microorganisms. It is also unexpected that a product is obtained that is both mild to the skin, pH-stabilizing and besides have a killing effect on microorganisms.
The main field of application for the composition according to the invention is in napkins for inhibiting and reduce the effect of skin irritations caused by degradation products from urine and faecal and to inhibit the growth of fungi and bacteria. It can however also be used in connection with other skin irritations, e.g. blisters.
Propylene glycol in the composition can be substituted by other diols with antimicrobial properties, e.g. butane diol.
The composition can besides contain other admixtures such as perfume and the like.