Phosphocreatine, sodium salt

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 - 16 June 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

Deviations:

yes

Remarks:

see principles of method if other than guideline

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

Regulation (EC) No 440/2008

Deviations:

yes

Remarks:

see principles of method if other than guideline

Principles of method if other than guideline:

Due to the high water solubility of the test item, the present study was conducted according to a modified TG OECD 105 design. Instead of equilibrating large amounts of test item (about five times in excess) with water by stirring over several days and subsequently separating the test item from the saturated solution, water was added in a stepwise procedure to a defined amount of test item until complete dissolution occurred.

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

Phosphocreatine, sodium salt

EC Number:

213-074-6

EC Name:

Phosphocreatine, sodium salt

Cas Number:

922-32-7

Molecular formula:

C4H8N3O5P.2Na

IUPAC Name:

sodium [carbamimidoyl(methyl)amino](phosphono)acetate

impurity 1

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Oxidane

Test material form:

solid: crystalline

Details on test material:

Batch No: 1413900

Specific details on test material used for the study:

Test item is hygroscopic and was therefore kept refrigerated and under nitrogen.

Results and discussion

Water solubility

Key result

Water solubility:

>= 524 g/L

Conc. based on:

test mat. (dissolved fraction)

Temp.:

22 °C

pH:

11

Details on results:

Preliminary test
The preliminary test indicated a water solubility of 200-1000 g/L.

Main test
The results are given in the table in the next section. The water solubility of Phosphocreatine, sodium salt was determined according to a modified TG OECD 105 design. The water solubility was determined as the mean of the replicates analysed with HPLC. As this method does not ensure complete saturation of the solution, it is given as a minimum value in mass per volume of solution.
The test is satisfactory, if the concentrations of the three vessels do not differ by more than 15%.

Any other information on results incl. tables

HPLC determinations:

Test vessel	pH	Analysed concentration A (g/L)	Analysed concentration B (g/L)	Mean
No. 1	11	527	525	526
No. 2	11	524	524	524
No. 3	11	519	526	523
			Overall Mean	524

The concentrations of the three vessels differed by 0.6% (validity criterion given by OECD is met).

Applicant's summary and conclusion

Conclusions:

The water solubility of Phosphocreatine, sodium salt (CAS no. 922-32-7) was determined according to a modified TG OECD 105 design.
The water solubility of the test item at 22°C was >=524 g/L. The pH of the aqueous samples was 11.

Executive summary:

The water solubility of Phosphocreatine, sodium salt (CAS no. 922-32-7) was determined according to a modified TG OECD 105 design.

To this end, increasing volumes of water were added in a stepwise procedure, to approximately 1 g of the test item at 22 ± 2 °C until complete dissolution, which occurred after addition of 1.4 mL of water. The concentration of test item was subsequently determined by HPLC with UV detection.

The determined water solubility of Phosphocreatine, sodium salt is >= 524 g/L at pH 11 and at 22 °C.