Stable oral compositions comprising casein phosphopeptide complexes and fluoride
The present invention relates to oral care compositions, especially toothpastes, comprising: a safe and effective amount of phosphopeptide-amorphous calcium phosphate complex (“PP-ACP”); a safe and effective amount of a fluoride ion source; a pharmaceutically-acceptable topical, oral carrier, and a safe and effective amount of a calcium chelator, wherein the composition has improved fluoride stability. This invention further relates to a method of maintaining the fluoride levels in an oral care composition comprising a safe and effective amount of PP-ACP, a safe and effective amount of a fluoride ion source, and a pharmaceutically-acceptable topical, oral carrier, by adding, to the composition, a safe and effective amount of a calcium chelator.
1. A method of maintaining the fluoride levels in an oral care composition comprising a safe and effective amount of PP-ACP, a safe and effective amount of a fluoride ion source with free fluoride ions, and a pharmaceutically-acceptable topical, oral carrier, by adding, to the composition, from about 0.001% to about 20% of a calcium chelator;
wherein the fluoride level for the aged composition is no more than about 20% lower than the level of fluoride in the fresh composition.
2. The method of claim 1 wherein the fluoride level for the aged composition is no more than about 15% lower than the level of fluoride in the fresh composition.
3. The method of claim 2 wherein the fluoride level for the aged composition is no more than about 10% lower than the level of fluoride in the fresh composition.
4. The method of claim 1 wherein the amount of PP-ACP is from about 0.1% to about 10% by weight of the composition.
5. The method of claim 4 wherein the level of PP-ACP is from about 0.2% to about 2% by weight of the composition.
6. The method of claim 5 wherein the calcium chelator is selected from the group consisting of tartaric acid and salts thereof, citric acid and salts thereof, pyrophosphate ion source, polyphosphate, diphosphonates, and mixtures thereof.
7. The method of claim 6 wherein the calcium chelator is selected from the group consisting of sodium citrate, potassium citrate, disodium tartrate, dipotassium tartrate, sodium potassium tartrate, disodium hydrogen tartrate, potassium hydrogen tartrate, pyrophosphate ion source, disodium dihydrogen pyrophosphate, tetrasodium pyrophosphate, tetrapotassium pyrophosphate, and mixtures thereof.
8. The method of claim 7 wherein the calcium chelator is a pyrophosphate ion source.
9. The method of claim 6 wherein the level of calcium chelator is from about 0.1% to about 5% by weight of the composition.
10. The method of claim 1 wherein the fluoride ion source provides free fluoride at a level of from about 850 ppm to about 1150 ppm of free fluoride ions.
11. The method of claim 1 wherein the PP-ACP contains the core sequence -Ser(P)-Ser(P)-Ser(P)-Glu-Glu-.
12. The method of claim 11 wherein PP includes the amino acid sequence selected from the group consisting of:
[1] Gln 59 -Met-Glu-Ala-Glu-Ser(P)-Ile-Ser(P)-Ser(P)-Ser(P)-Glu-Glu-Ile-Val-Pro-Asn-Ser(P)-Val-Glu-Gln-Lys 79 α s1 (59-79) (T 1 );
[2] Arg 1 -Glu-Leu-Glu-Glu-Leu-Asn-Val-Pro-Gly-Glu-Ile-Val-Glu-Ser(P)-Leu-Ser(P)-Ser(P)-Ser(P)-Glu-Glu-Ser-Ile-Thr-Arg 25 β(1-25) (T 2 );
[3] Asn 46 -Ala-Asn-Glu-Glu-Glu-Tyr-Ser-Ile-Gly-Ser(P)-Ser(P)-Ser(P)-Glu-Glu-Ser(P)-Ala-Glu-Val-Ala-Thr-Glu-Glu-Val-Lys 70 α s2 (46-70) (T 4 ); and
[4] Lys 1 -Asn-Thr-Met-Glu-His-Val-Ser(P)-Ser(P)-Ser(P)-Glu-Glu-Ser-Ile-Ile-Ser(P)-Gln-Glu-Thr-Tyr-Lys 21 α s2 (1-21) (T3).
13. The method of claim 1 wherein ACP is an amorphous form of calcium phosphate having the formula: Ca 3 (PO 4 ) 1.87 (HPO 4 ) 0.2 xH 2 O where x≧1.