reaction mass of sodium 1-amino-4-[[3,5-bis[[(chloroacetyl)amino]methyl]-2,4,6-trimethylphenyl]amino]-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate and sodium 1-amino-4-[[3-[[(chloroacetyl)amino]methyl]-2,4,6-trimethylphenyl]amino]-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September from 10 to 20, 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

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Version / remarks:

1995

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

GLP compliance:

no

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

-0.5

Temp.:

25 °C

pH:

ca. 3.8

Details on results:

The phases of the shake-flask-method were measured twice by means of HPLC.
To verify the accuracy of the analytical method two fresh prepared standard solutions in double distilled water (prepared with the test item) and two in acetonitrile were measured in between the samples of the shake-flask-method. The recovery rate of the measured standard solutions was in the range from 98.6 to 102.3 %, which shows a good accuracy of the analytical method.

PRELIMINARY TEST
The preliminary test at room temperature showed that the octanol solubility of the test item was between 0.5 and 1.1 g/l. The water solubility of 12.9 g/l at 20 °C was determined in the specific study. Thus, the partition coefficient was estimated to be between -2.1 and -1.4.

Results of the shake-flask-method

separating funnel	total amount of test item in the separating funnel (mg)	recovery rate (%)	Pow	log Pow
1a	130.5	102.6	0.31	-0.5
1b	132.9	104.5	0.40	-0.4
2a	141.4	111.2	0.40	-0.4
2b	146.0	114.8	0.45	-0.4
3a	130.1	102.3	0.20	-0.7
3b	129.8	102.1	0.20	-0.7
mean value				-0.5
standard deviation				0.2

Concentrations in the aqueous phases

separating funnel	pH values*	measured concentration (mg/l)	mean concentration**(mg/l)
1a	3.8	56.2 / 56.7	2824.3
1b	3.8	55.3 / 55.2	2762.9
2a	3.9	50.4 / 50.5	2524.5
2b	3.9	50.1 / 50.9	2525.6
3a	3.8	93.2 / 94.4	4689.3
3b	3.8	93.7 / 92.7	4658.5

*at temperatures of 25.0 – 25.7 °C

**under consideration of the dilution factor 50

Concentrations in the octanol phases

separating funnel	measured concentration (mg/l)	mean concentration*(mg/l)
1a	87.4 / 87.4	874.0
1b	112.1 / 111.3	1116.9
2a	100.5 / 101.5	1010.1
2b	112.5 / 112.3	1124.0
3a	91.3 / 90.4	908.6
3b	92.0 / 91.4	916.8

*Under consideration of the dilution factor 10

Conclusions:

log Pow: -0.5 ± 0.2 at 25 - 26 °C and pH ca 3.8

Executive summary:

The partition coefficient of the test item was determined using shake-flask method, in accordante with the method and procedures outlined into the OECD guideline 107. The concentration in the aqueous and octanol phases was determined by HPLC-UV validate method. On the basis of the preliminary assay, the value of the partition coefficient was estimated to be between -2.1 and 1.4.

Three experiments were carried out applying different solvent ratios.

In the first experiment, the calculated volume ratio was applied, in the second, this ratio is divided by two and in the third, this ratio is multiplied by two. Test temperature was 25 - 26 °C.

An HPLC method using UV-VIS detection has been validated for the quantification of the test item in ultra-pure water and in n-octanol.

The procedure was found to be suitable for the analysis.

The partition coefficient log Pow resulted to be -0.5 ± 0.2 at 25 - 26 °C and pH ca 3.8.

To verify the accuracy of the analytical method two fresh prepared standard solutions in double distilled water (prepared with the test item) and two in acetonitrile were measured in between the samples of the shake-flask-method. The recovery rate of the measured standard solutions was in the range from 98.6 to 102.3 %, which shows a good accuracy of the analytical method.

Conclusion

log Pow: -0.5 ± 0.2 at 25 - 26 °C and pH ca 3.8

Description of key information

log Pow: -0.5 ± 0.2 at 25 - 26 °C and pH ca 3.8

Key value for chemical safety assessment

Log Kow (Log Pow):

-0.5

at the temperature of:

25 °C

Additional information

OECD 107 - Shake-flask method