COSMETIC COMPOSITION OF LOW OSMOLALITY

Abstract

The present invention generally relates to the field of skin care. More particularly, the invention relates to a skin care composition that has a particularly low osmolality. The skin care composition of the invention therefore is specifically suitable for supporting the skin microbiome, because it does not create an osmotic stress that would be harmful to the bacteria after its topical application to the skin. Accordingly, skin care composition of the invention preserves and improves the vitality of the bacteria of the skin microbiome, which enhances the stability of a healthy skin microbiome. The skin care composition of the present invention can be thus used for treating or preventing skin diseases, for promoting the development of a healthy skin microbiome, for stabilizing a healthy skin microbiome, and for maintaining or promoting the vitality of bacteria of the skin microbiome.

Claims

1.-15. (canceled)

16. A skin care composition for maintaining or promoting the vitality of bacteria on the skin surface, wherein the composition (a) is an aqueous composition which is formulated for topical application to skin, and (b) has an osmolality of 4000 mOsm/kg water or less.

17. The skin care composition of claim 16, wherein the composition has an osmolality of 3800 mOsm/kg water or less.

18. The skin care composition of claim 16, wherein the composition has an osmolality is 3500 mOsm/kg water or less.

19. The skin care composition of claim 16, wherein the composition comprises at least 30% water (w/w).

20. The skin care composition of claim 16, wherein the composition comprises at least 50% water (w/w).

21. The skin care composition of claim 16, wherein the composition comprises at least 70% water (w/w).

22. The skin care composition of claim 18, wherein the composition comprises at least 70% water (w/w).

23. The skin care composition of claim 16, wherein the composition is present as a gel.

24. The skin care composition of claim 16, wherein the composition comprises less than 0.5% (w/w) of NaCl.

25. The skin care composition of claim 16, wherein the composition comprises less than 0.1% (w/w) of NaCl.

26. The skin care composition of claim 16, wherein the composition comprises less than 5% (w/w) of glycerol.

27. The skin care composition of claim 16, wherein the composition comprises less than 1% (w/w) of glycerol.

28. The skin care composition of claim 25, wherein the composition comprises less than 1% (w/w) of glycerol.

29. The skin care composition of claim 16, wherein the composition further comprises one or more of a perfume, an emollient, a pigment, a thickener, a filler, a colorant, an antioxidant, a surfactant, a lubricant, a stabilizer, a preservative, a solubilizer, an emulsifier.

30. A skin care composition for maintaining or promoting the vitality of bacteria on the skin surface, wherein the composition (a) is a gel which is formulated for topical application to skin, (b) has an osmolality of 3500 mOsm/kg water or less, and (c) comprises at least 50% water (w/w).

31. The skin care composition of claim 30, wherein the composition comprises less than 0.1% (w/w) of NaCl.

32. The skin care composition of claim 30, wherein the composition comprises less than 1% (w/w) of glycerol.

33. The skin care composition of claim 31, wherein the composition comprises less than 1% (w/w) of glycerol.

34. A method of treating a skin disease, wherein the method comprises applying to skin affected by the skin disease the skin care composition of claim 16 in an amount which is effective to treat the skin disease.

35. The method of claim 34, wherein the skin disease is acne.

Description

BRIEF DESCRIPTION OF THE FIGURE

[0208] FIG. 1 shows the general procedure of the AlamarBlue Forearm Test to measure the viability of the bacterial cells on the skin surface in response to the test formulas.

[0209] FIG. 2 is a bar diagram showing the results of the AlamarBlue Forearm Test to measure the viability of the bacterial cells on the skin surface in response to the test formulas. It can be seen that hydrogels having a reduced osmolality maintain viability of the bacterial cells much better compared to a standard hydrogel.

[0210] FIG. 3 is a bar diagram showing the results of the AlamarBlue Forearm Test to measure the viability of the bacterial cells on the skin surface in response to the test formulas. It can be seen that hydrogels having a reduced osmolality (n=4) maintain viability of the bacterial cells much better compared to a standard hydrogel (n=6).

EXAMPLES

[0211] The present invention is further illustrated by the following examples, which in no way should be construed as limiting. The entire contents of all of the references (including literature references, issued patents, published patent applications, and co pending patent applications) cited throughout this application are hereby expressly incorporated by reference.

Example 1: Formulation of Standard and Test Gels

[0212] The following 4 standard gels were formulated. The amounts of osmotically active compounds in the gels were selected as commonly used in the field. The theoretical osmolality of the compositions was calculated.

[0213] Standard Gel 1:

TABLE-US-00001 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 7.5 75 92.09 1.040288008 1 1.040 Citric acid 0.02 0.2 210.03 0.001216336 3 0.003649007 Sodium Citrate 0.174 1.74 215.03 0.010336059 4 0.041344237 Caustic Soda 0.017 0.17 40 0.005428674 2 0.010857347 Ethanol 11.466 114.66 46.07 3.179058552 1 3.179058552 Sodium Chloride 0.9 9 58.5 0.196513072 2 0.393026144 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0 0 120.37 0 2 0 Carbomer 1 10 0 Sodium Hyaluronate 0 0 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006797951 1 0.006797951 ated Castor Oil Water 78.28800 782.88 0 Total: 100 1000 4.675

[0214] Standard Gel 2:

TABLE-US-00002 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 7.5 75 92.09 1.036976591 1 1.037 Citric acid 0.02 0.2 210.03 0.001212464 3 0.003637392 Sodium Citrate 0.174 1.74 215.03 0.010303158 4 0.041212632 Caustic Soda 0.017 0.17 40 0.005411393 2 0.010822786 Ethanol 11.466 114.66 46.07 3.16893906 1 3.16893906 Sodium Chloride 0.9 9 58.5 0.195887537 2 0.391775074 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0 0 120.37 0 2 0 Carbomer 0 0 0 Sodium Hyaluronate 0.75 7.5 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006776312 1 0.006776312 ated Castor Oil Water 78.53800 785.38 Total: 100 1000 4.660

[0215] Standard Gel 3:

TABLE-US-00003 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 7.5 75 92.09 1.036976591 1 1.037 Citric acid 0.02 0.2 210.03 0.001212464 3 0.003637392 Sodium Citrate 0.174 1.74 215.03 0.010303158 4 0.041212632 Caustic Soda 0.017 0.17 40 0.005411393 2 0.010822786 Ethanol 11.466 114.66 46.07 3.16893906 1 3.16893906 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0.9 9 95.21 0.120359426 3 0.361078277 Magnesium Sulfate 0 0 120.37 2 0 Carbomer 0 0 0 Sodium Hyaluronate 0.75 7.5 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006776312 1 0.006776312 ated Castor Oil Water 78.53800 785.38 0 Total: 100 1000 4.629

[0216] Standard Gel 4:

TABLE-US-00004 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 7.5 75 92.09 1.040288008 1 1.040 Citric acid 0.02 0.2 210.03 0.001216336 3 0.003649007 Sodium Citrate 0.174 1.74 215.03 0.010336059 4 0.041344237 Caustic Soda 0.017 0.17 40 0.005428674 2 0.010857347 Ethanol 11.466 114.66 46.07 3.179058552 1 3.179058552 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0.9 9 120.37 0.095505647 2 0.191011294 Carbomer 1 10 0 Sodium Hyaluronate 0 0 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006797951 1 0.006797951 ated Castor Oil Water 78.28800 782.88 0 Total: 100 1000 4.473

[0217] In addition, the following 4 gels with reduced osmolality were formulated. The amounts of osmotically active compounds in these gels were selected to be lower than the amounts commonly used in the field. The theoretical osmolality of the compositions was calculated.

[0218] Test Gel 1 with Reduced Osmolality:

TABLE-US-00005 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 2.5 25 92.09 0.321735382 1 0.322 Citric acid 0.002 0.02 210.03 0.000112855 3 0.000338564 Sodium Citrate 0.0174 0.174 215.03 0.000959006 4 0.003836025 Caustic Soda 0.0017 0.017 40 0.000503686 2 0.001007373 Ethanol 11.466 114.66 46.07 2.949612824 1 2.949612824 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0 0 120.37 0 2 0 Carbomer 1 10 0 Sodium Hyaluronate 0 0 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006307315 1 0.006307315 ated Castor Oil Water 84.37790 843.779 0 Total: 100 1000 3.283

[0219] Test Gel 2 with Reduced Osmolality:

TABLE-US-00006 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 2.5 25 92.09 0.32078494 1 0.321 Citric acid 0.002 0.02 210.03 0.000112521 3 0.000337564 Sodium Citrate 0.0174 0.174 215.03 0.000956173 4 0.003824693 Caustic Soda 0.0017 0.017 40 0.000502198 2 0.001004397 Ethanol 11.466 114.66 46.07 2.940899347 1 2.940899347 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0 0 120.37 0 2 0 Carbomer 0 0 0 Sodium Hyaluronate 0.75 7.5 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006288682 1 0.006288682 ated Castor Oil Water 84.62790 846.279 0 Total: 100 1000 3.273

[0220] Test Gel 3 with Reduced Osmolality:

TABLE-US-00007 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 1 10 92.09 0.126446296 1 0.126 Citric acid 0.002 0.02 210.03 0.000110884 3 0.000332651 Sodium Citrate 0.0174 0.174 215.03 0.000942256 4 0.003769023 Caustic Soda 0.0017 0.017 40 0.000494889 2 0.000989777 Ethanol 11.466 114.66 46.07 2.898092942 1 2.898092942 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0 0 95.21 0 3 0 Magensium Sulfate 0 0 120.37 0 2 0 Carbomer 1 10 0 Sodium Hyaluronate 0 0 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006197147 1 0.006197147 ated Castor Oil Water 85.87790 858.779 0 Total: 100 1000 3.036

[0221] Test Gel 4 with Reduced Osmolality:

TABLE-US-00008 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0 0 Glycerine 2.5 25 92.09 0.320274033 1 0.320 Citric acid 0.002 0.02 210.03 0.000112342 3 0.000337027 Sodium Citrate 0.0174 0.174 215.03 0.00095465 4 0.003818602 Caustic Soda 0.0017 0.017 40 0.000501399 2 0.001002797 Ethanol 11.466 114.66 46.07 2.936215442 1 2.936215442 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0 0 120.37 0 2 0 Carbomer 0 0 0 Sodium Hyaluronate 0.75 7.5 0 PEG-40 Hydrogen- 0.5 5 939.5 0.006278666 1 0.006278666 ated Castor Oil Water 84.76290 847.629 0 Total: 100 1000 3.268

Example 2: AlamarBlue Forearm Test

[0222] Before the test is performed, 4 areas of 25 cm.sup.2 to be tested are marked on the forearm of the test subjects. Then, a defined amount of the respective formulas are applied leaving one test area untreated for control. At the respective points in time (T05 min after application, T1after 1.5 h, T2after 3 h) skin rinsing samples are taken using the swab technique. After sampling, the swab remains in the rinsing solution. As a reference for comparison, the respective formula is pipetted into bacterial medium (CAB) and also incubated for the appropriate time. Then the sample and the reference are diluted and mixed with the AlamarBlue reagent. A triple determination is performed in each case. The test plate is incubated at 37 C. for 3 hours and then the fluorescence (RLU) is determined in the plate reader. The steps of the test are depicted in FIG. 1.

[0223] Results: The results of the AlamarBlue forearm test for Standard Gel 2 and the reduced Test Gel 2 (with reduced osmolality) are depicted in FIGS. 2 and 3. A significant decrease in the viability of the resident skin bacteria was observed after use of the standard formula. In contrast, the reduced formula was more suited to maintain viability of the cells 3 h after application of the formulas. Essentially the same difference was observed when testing the other Standard Gels and comparing them to the Test Gels.

[0224] The effect of osmolality is further enhanced by the ethanol that is present in the gels. After application to the skin, the ethanol and most of the water evaporates which leads to a concentration of the remaining solutes. This results in a significant increase in the osmolality of the Standard Gel. In contrast, as shown below, the osmolality of the Test Gel 2 was low also after ethanol evaporation, therefore imposing less stress on the skin bacteria.

[0225] Standard Gel 2 after Ethanol Evaporation:

TABLE-US-00009 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 7.5 75 92.09 9.048716451 1 9.049 Citric acid 0.02 0.2 210.03 0.010580029 3 0.031740087 Sodium Citrate 0.174 1.74 215.03 0.089905939 4 0.359623757 Caustic Soda 0.017 0.17 40 0.047220124 2 0.094440247 Ethanol 0 0 46.07 0 1 0 Sodium Chloride 0.9 9 58.5 1.709325739 2 3.418651479 Magnesium Chloride 0 0 95.21 0 3 Magnesium Sulfate 0 0 120.37 0 2 Carbomer 0 0 Sodium Hyaluronate 0.75 7.5 PEG-40 Hydrogen- 0.5 5 939.5 0.059130481 1 0.059130481 ated Castor Oil Water 9.00040 90.004 Total: 18.9964 189.964 13.012

[0226] Test Gel 2 after Ethanol Evaporation:

TABLE-US-00010 Osmolality Number Mol Molar Mol/kg particles/ particles/kg g per kg mass Water ions Water Perfume 0.135 1.35 Glycerine 2.5 25 92.09 2.82508628 1 2.825 Citric acid 0.002 0.02 210.03 0.000990953 3 0.002972858 Sodium Citrate 0.0174 0.174 215.03 0.00842082 4 0.033683279 Caustic Soda 0.0017 0.017 40 0.004422757 2 0.008845515 Ethanol 0 0 46.07 0 1 0 Sodium Chloride 0 0 58.5 0 2 0 Magnesium Chloride 0 0 95.21 0 3 0 Magnesium Sulfate 0 0 120.37 0 2 0 Carbomer 0 0 Sodium Hyaluronate 0.75 7.5 PEG-40 Hydrogen- 0.5 5 939.5 0.055383118 1 0.055383118 ated Castor Oil Water 9.60939 96.0939 Total: 13.51549 135.155 2.926