Disodium 7-[[2-(acetylamino)-4-[(5-chloro-2,6-difluoro-4-pyrimidinyl)amino]phenyl]azo]naphthalene-1,3-disulphonate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July from 23rs to 28th, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Reason / purpose for cross-reference:

reference to other study

Remarks:

validation of analytical method

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

adopted July 27, 1995

Deviations:

yes

Remarks:

not impacting the reliability of the test results (details below)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

19 March 2014

Deviations:

yes

Remarks:

not impacting the reliability of the test results (details below)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7840 (Water Solubility)

Version / remarks:

March 1998

Deviations:

yes

Remarks:

not impacting the reliability of the test results (details below)

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

131.93 g/L

Conc. based on:

test mat.

Incubation duration:

24 - 72 h

Temp.:

20 °C

pH:

ca. 4.8

Details on results:

The water solubility of test item was determined to be 131.93 ± 6.46 g/l (95 % confidence interval) at 20 ± 0.5 °C and pH ca 4.8.
The repeatability of the determination was < 15 % and thus within the range required by the guidelines.

Sampling time	Measured concentration of test item, g/l		Measured pH
	Test vessels	Mean
after 24 hours	129.32	134.94	4.8
	135.31		4.8
	140.17		4.8
after 48 hours	145.97	130.41	4.7
	113.51		4.7
	131.75		4.8
after 72 hours	133.41	130.46	4.8
	112.05		4.8
	145.91		4.8
Mean with confidence interval (95 %)	-	131.93 ± 6.46	-
RSD %	-	2	-

Conclusions:

Water solubility: 131.93 ± 6.46 g/l at 20 ± 0.5 °C and pH ca 4.8.

Executive summary:

The water solubility of the test matarial was investigated according to the OECD guideline 105. A preliminary test for solubility was carried out as a range finding test and the solubility of the test item was higher than 10 mg/l; therefore, the flask method was used for the main test.

Amount of test item was weighed and additioned of 50 ml ultrapure water, the flasks were agitated at 30 °C. After one day, three of the vessels were removed and re-equilibrated at 20 °C for 24 hours. The content of the vessel was then centrifuged at 20 °C and the concentration in the clear aqueous phase was determined by HPLC. The other flasks were treated similarly after initial equilibration at 30 °C for two and three days, respectively. The samples were diluted before the analysis (two parallel dilutions). The pH of each sample was recorded.

The saturated samples were centrifuged at 20 °C, at 13000 rpm (5 min). The clear solvent phase was diluted with ultrapure water and measured using the previously validated reverse phase HPLC method.

The water solubility of test item was determined to be 131.93 ± 6.46 g/l (95 % confidence interval) at 20 ± 0.5 °C and pH ca 4.8.

Conclusion

Water solubility: 131.93 ± 6.46 g/l at 20 ± 0.5 °C and pH ca 4.8.

Description of key information

131.93 ± 6.46 g/l at 20 ± 0.5 °C and pH ca 4.8.

Key value for chemical safety assessment

Water solubility:

131.93 g/L

at the temperature of:

20 °C

Additional information

OECD 105 - Flask method