Reaction mass of [5-methyl-2-[[4-(4-methylanilino)-9,10-dioxo-1-anthryl]amino]phenyl]sulfonyloxypotassium and [5-methyl-2-[[4-(4-methyl-2-potassiooxysulfonyl-anilino)-9,10-dioxo-1-anthryl]amino]phenyl]sulfonyloxypotassium

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 3 to 21 November, 2017

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:

adopted in 1995

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

-0.2

Temp.:

25 °C

pH:

5.4 - 5.9

Details on results:

MAIN TEST
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 for both phases (prepared with the test item) were measured in between the samples of the shake-flask-method.

PRELIMINARY TEST
The preliminary test at room temperature showed, that the octanol solubility of the test item was <0.1808 g/l. With the determined solubility in water of 15.94 g/l and 1-octanol from these preliminary tests, the partition coefficient log Pow can be estimated to be approx.-1.9.

Results of the shake flask method

separating funnel	total amount of test item in the separating funnel (mg)	recovery rate (%)	POW	log POW
1a	119.67	97.2	1.27	0.1
1b	121.46	98.7	1.44	0.2
2a	114.7	93.2	0.67	-0.2
2b	114.85	93.3	0.65	-0.2
3a	116.78	94.9	0.34	-0.5
3b	115.17	93.6	0.33	-0.5
mean value				-0.2
standard deviation				0.25

Concentrations in the aqueous phases

separating funnel	pH values^*1	measured concentration (mg/l)	mean concentration^*2(mg/l)
1a	5.42	36.58 / 36.60	1.83
1b	5.68	35.28 / 35.21	1.76
2a	5.69	34.23 / 34.46	1.72
2b	5.88	34.97 / 34.72	1.74
3a	5.74	69.27 / 69.39	3.47
3b	5.63	68.92 / 69.25	3.45

*1 at temperatures of 24.5 – 25.1 °C

*2 under consideration of the dilution factor 50

Concentrations in the octanol phases

separating funnel	measured concentration (mg/l)	mean concentration^*1(mg/l)
1a	46.44 / 46.55	2.32
1b	50.98 / 50.97	2.55
2a	22.88 / 23.12	1.15
2b	22.57 / 22.59	1.13
3a	23.66 / 23.79	1.19
3b	22.95 / 23.14	1.15

*1 under consideration of the dilution factor 50

Meaurement of standard solutions

Standard solution (nominal value [mg/l])	Measured value [mg/l]	Recovery rate [%]
aqueous-1 -58.6	57.03	97.3
	56.98	97.2
	56.63	96.6
aqueous-2 -80.2	79.39	99.0
	79.18	98.7
	79.07	98.6
octanol-1 -24.46	24.05	98.3
	24.22	99.0
	24.01	98.2
octanol-2 -49.22	48.31	98.1
	48.14	97.8
	47.82	97.2

Conclusions:

log Pow: -0.2 ± 0.3 at 25 °C and pH 5.4 - 5.9

Executive summary:

The partition coefficient of test item was determined by shake-flask method following the procedures outlined into the OECD guideline 107. The experiments were carried out applying volume ratios and quantities of the test substance depending on expected partition and the LOQ of the analytical method in both phases. Three parallel tests were carried out at all solvent ratios.

The logarithm of partition coefficient (logPow) of test item in n-octanol-water was determined to be -0.2 ± 0.3 at 25 °C and pH 5.4 - 5.9

Conclusion

log Pow: -0.2 ± 0.3 at 25 °C and pH 5.4 - 5.9

Description of key information

log Pow: -0.2 ± 0.3 at 25 °C and pH 5.4 - 5.9

Key value for chemical safety assessment

Log Kow (Log Pow):

-0.2

at the temperature of:

25 °C

Additional information

OECD 107 - Shake-flask method