Alkali metal tetrakis (perfluoro-alcoholato)metallate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Version / remarks:

13.4.2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Appearance: white powder

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

6.001

Temp.:

25 °C

pH:

4

Type:

log Pow

Partition coefficient:

5.691

Temp.:

25 °C

pH:

7

Type:

log Pow

Partition coefficient:

5.806

Temp.:

25 °C

pH:

9

Details on results:

Variations in the retention times of reference items and test item are very small. Therefore, a stable configuration of the HPLC-column can be assumed.
The correlation log k/log Pow is good: the coefficient of determination r² was calculated with 0.9893 (pH 4), 0.9892 (pH 7) and 0.9893 (pH 9). These values were considered as sufficiently high to use the calibration function for the determination of the log Pow of the test item AM(pfa)4.
The chromatogram of the test item AM(pfa)4 gave one peak with a retention time of 2.009 (mean, pH 4), 1.615 (mean, pH 7) and 1.757 min (mean, pH 9).
Using the correlation log k / log Pow, the log Pow of the test item AM(pfa)4 was calculated as 6.001 ±0.006 (for pH 4), 5.691 ±0.001 (for pH 7) and 5.806 ±0.001 (for pH 9) (mean ±standard deviation).
Therefore, the log Pow of the test item AM(pfa)4 was stated as:
6.0 (for pH 4)
5.7 (for pH 7)
5.8 (for pH 9)
No observations were made which might cause doubts concerning the validity of the study outcome.

Reference Items, buffer pH4

The retention times which were recorded for the reference items are presented in the following table.

Table 3: Retention Times (RT) Reference Items, buffer pH 4

Compound	RT 1	RT 2	RT 3	RT 4	RT 5	RT 6
	min.	min.	min.	min.	min.	min.
Thiourea	0.234	0.234	0.233	0.234	0.234	0.234
Acetophenone	0.303	0.303	0.303	0.304	0.303	0.303
Naphthalene	0.534	0.535	0.534	0.537	0.536	0.536
Diphenyl ether	0.652	0.652	0.652	0.654	0.654	0.653
Phenanthrene	0.908	0.910	0.909	0.913	0.913	0.912
Fluoranthene	1.221	1.222	1.222	1.229	1.229	1.227
Triphenylamine	1.799	1.801	1.802	1.813	1.813	1.811
4,4’-DDT	2.372	2.375	2.377	2.398	2.394	2.392

 

For each reference item, the calculated capacity factors are presented in the following table.

Table 4: Capacity factors Reference Items, buffer pH 4

Compound	Retention Time Mean	Retention Time Standard Deviation	Retention Time Relative Standard Deviation	k
	min.	min.	%
Thiourea	0.234	0.000	0.175	0
Acetophenone	0.303	0.000	0.135	0.2965
Naphthalene	0.535	0.001	0.226	1.2894
Diphenyl ether	0.653	0.001	0.151	1.7919
Phenanthrene	0.911	0.002	0.235	2.8952
Fluoranthene	1.225	0.004	0.305	4.2388
Triphenylamine	1.807	0.007	0.360	6.7256
4,4’-DDT	2.385	0.011	0.471	9.1981

 

log Pow / log k: The values for log k and log Pow of the reference items are presented in the following table:

Table 5: log k and log Pow of Reference Items, buffer pH 4

Compound	log k	log Pow
Acetophenone	-0.5280	1.70
Naphthalene	0.1104	3.60
Diphenyl ether	0.2533	4.20
Phenanthrene	0.4617	4.50
Fluoranthene	0.6272	5.10
Triphenylamine	0.8277	5.70
4,4’-DDT	0.9637	6.50

 

Calibration at pH 4 and Correlation Results: Dead time is 0.234 ±0.000 minutes, with RSD (relative standard deviation) 0.175 %. The RSD of the retention times of the reference items lay all below 0.5 %.

Equation of the regression: log k = 0.3218 * log Pow – 1.051, with a coefficient of determination r² = 0.9893.

 

Test Item AM(pfa)4, buffer pH 4

The retention times of the test item are presented in the following table:

Table 6: Retention Times (RT) Test Item, buffer pH 4

Measurement	RT
	min.
Measurement 1	2.018
Measurement 2	2.005
Measurement 3	2.005
Mean	2.009
Standard deviation	0.008

 

Calculated Values: The calculated values are presented in the following table:

Table 7: Capacity Factor, log Capacity Factor, log Pow Test Item, buffer pH 4

Measurement	k	log k	log POW
Measurement 1	7.6301	0.8825	6.008
Measurement 2	7.5745	0.8794	5.998
Measurement 3	7.5745	0.8794	5.998
Mean			6.001
Relative Standard deviation			0.006

 

log Pow was calculated from the capacity factor as follows: log Pow = (log k + 1.051) / 0.3218

 

Results and Validity, buffer pH 4: The chromatogram of the test item AM(pfa)4 gave one peak with a retention time of 2.009 min (mean). Using the correlation log k / log Pow, the log Pow of the test item AM(pfa)4 in buffer pH 4 was calculated as 6.001 ± 0.006 (mean ± standard deviation).

Validity: The validity criteria and results are presented in the following table:

Table 8: Validity Criteria and Results, buffer pH 4

Peak	Parameter	Criterion	Found	Assessment
1	Range (Max – Min. log Pow)	< 0.1	0.010	valid
	Value within Range of Ref. Items	0.303 - 2.385	2.009	valid

 

Reference Items, buffer pH 7

The retention times which were recorded for the reference items are presented in the following table.

Table 9: Retention Times (RT) Reference Items, buffer pH 7

Compound	RT 1	RT 2	RT 3	RT 4	RT 5	RT 6
	min.	min.	min.	min.	min.	min.
Thiourea	0.234	0.234	0.235	0.235	0.234	0.234
Acetophenone	0.303	0.304	0.304	0.304	0.303	0.303
Naphthalene	0.532	0.533	0.532	0.532	0.530	0.531
Diphenyl ether	0.648	0.649	0.647	0.647	0.645	0.647
Phenanthrene	0.902	0.902	0.900	0.899	0.896	0.900
Fluoranthene	1.207	1.209	1.205	1.204	1.200	1.204
Triphenylamine	1.786	1.788	1.779	1.778	1.772	1.778
4,4’-DDT	2.342	2.342	2.330	2.330	2.321	2.329

 

For each reference item, the calculated capacity factors are presented in the following table.

Table 10: Capacity factors Reference Items, buffer pH 7

Compound	Retention Time Mean	Retention Time Standard Deviation	Retention Time Relative Standard Deviation	k
	min.	min.	%
Thiourea	0.234	0.001	0.220	0
Acetophenone	0.304	0.001	0.180	0.2952
Naphthalene	0.532	0.001	0.194	1.2688
Diphenyl ether	0.647	0.001	0.205	1.7617
Phenanthrene	0.900	0.002	0.248	2.8400
Fluoranthene	1.205	0.003	0.254	4.1415
Triphenylamine	1.780	0.006	0.330	6.5967
4,4’-DDT	2.332	0.008	0.352	8.9531

 

log Pow / log k: The values for log k and log Pow of the reference items are presented in the following table:

Table 11: log k and log Pow of Reference Items, buffer pH 7

Compound	log k	log Pow
Acetophenone	-0.5299	1.70
Naphthalene	0.1034	3.60
Diphenyl ether	0.2459	4.20
Phenanthrene	0.4533	4.50
Fluoranthene	0.6172	5.10
Triphenylamine	0.8193	5.70
4,4’-DDT	0.9520	6.50

 

Correlation Results: Dead time is 0.234 ±0.001 minutes, with RSD (relative standard deviation) 0.22 %. The RSD of the retention times of the reference items lay all below 0.4 %.

Equation of the regression: log k = 0.32 * log Pow – 1.0505, with a coefficient of determination r² = 0.9892.

 

Test Item AM(pfa)4, buffer pH 7: The retention times of the test item are presented in the following table:

Table 12: Retention Times (RT) Test Item, buffer 7

Measurement	RT
	min.
Measurement 1	1.616
Measurement 2	1.616
Measurement 3	1.614
Mean	1.615
Standard deviation	0.001

 

Calculated Values: The calculated values are presented in the following table:

Table 13: Capacity Factor, log Capacity Factor, log Pow Test Item, buffer 7

Measurement	k	log k	log Pow
Measurement 1	5.8962	0.7706	5.692
Measurement 2	5.8962	0.7706	5.692
Measurement 3	5.8876	0.7699	5.690
Mean			5.691
Relative Standard deviation			0.001

 

log Pow was calculated from the capacity factor as follows: log Pow = (log k + 1.0505) / 0.32

 

Results and Validity, buffer pH 7

Result: The chromatogram of the test item AM(pfa)4 gave one peak with a retention time of 1.615 min (mean). Using the correlation log k / log Pow, the log Pow of the test item AM(pfa)4 in buffer pH 7 was calculated as 5.691 ±0.001 (mean ±standard deviation).

Validity: The validity criteria and results are presented in the following table:

Table 14: Validity Criteria and Results, buffer pH 7

Peak	Parameter	Criterion	Found	Assessment
1	Range (Max – Min. log POW)	< 0.1	0.002	valid
	Value within Range of Ref. Items	0.304 - 2.332	1.615	valid

 

Reference Items, buffer pH 9

The retention times which were recorded for the reference items are presented in the following table.

Table 15: Retention Times (RT) Reference Items, buffer pH 9

Compound	RT 1	RT 2	RT 3	RT 4	RT 5	RT 6
	min.	min.	min.	min.	min.	min.
Thiourea	0.233	0.235	0.235	0.233	0.233	0.235
Acetophenone	0.303	0.304	0.304	0.303	0.303	0.304
Naphthalene	0.532	0.534	0.534	0.533	0.534	0.536
Diphenyl ether	0.647	0.651	0.651	0.650	0.652	0.653
Phenanthrene	0.903	0.906	0.907	0.907	0.908	0.911
Fluoranthene	1.213	1.216	1.218	1.217	1.219	1.223
Triphenylamine	1.789	1.790	1.794	1.795	1.798	1.803
4,4’-DDT	2.355	2.356	2.363	2.364	2.368	2.377

 

For each reference item, the calculated capacity factors are presented in the following table.

Table 16: Capacity factors Reference Items, buffer pH 9

Compound	Retention Time Mean	Retention Time Standard Deviation	Retention Time Relative Standard Deviation	k
	min.	min.	%
Thiourea	0.234	0.001	0.468	0
Acetophenone	0.304	0.001	0.180	0.2970
Naphthalene	0.534	0.001	0.249	1.2813
Diphenyl ether	0.651	0.002	0.317	1.7806
Phenanthrene	0.907	0.003	0.288	2.8761
Fluoranthene	1.218	0.003	0.273	4.2037
Triphenylamine	1.795	0.005	0.289	6.6702
4,4’-DDT	2.364	0.008	0.344	9.1019

 

log Pow / log k: The values for log k and log Pow of the reference items are presented in the following table:

Table 17: log k and log Pow of Reference Items, buffer pH 9

Compound	log k	log Pow
Acetophenone	-0.5272	1.70
Naphthalene	0.1077	3.60
Diphenyl ether	0.2506	4.20
Phenanthrene	0.4588	4.50
Fluoranthene	0.6236	5.10
Triphenylamine	0.8241	5.70
4,4’-DDT	0.9591	6.50

 

Correlation Results: Dead time is 0.234 ±0.001 minutes, with RSD (relative standard deviation) 0.468 %. The RSD of the retention times of the reference items lay all below 0.3 %.

Equation of the regression: log k = 0.3208 * log Pow – 1.0492, with a coefficient of determination r² = 0.9893.

 

Test Item AM(pfa)4, buffer pH 9

The retention times of the test item are presented in the following table:

Table 18: Retention Times (RT) Test Item, buffer 9

Measurement	RT
	min.
Measurement 1	1.756
Measurement 2	1.756
Measurement 3	1.758
Mean	1.757
Standard deviation	0.001

 

The calculated values are presented in the following table:

Table 19: Capacity Factor, log Capacity Factor, log Pow Test Item, buffer 9

Measurement	k	log k	log POW
Measurement 1	6.5043	0.8132	5.805
Measurement 2	6.5043	0.8132	5.805
Measurement 3	6.5128	0.8138	5.807
Mean			5.806
Relative Standard deviation			0.001

 

log Pow was calculated from the capacity factor as follows: log Pow = (log k + 1.0492) / 0.3208

 

Results and Validity, buffer pH 9

Result: The chromatogram of the test item AM(pfa)4 gave one peak with a retention time of 1.757 min (mean). Using the correlation log k / log Pow, the log Pow of the test item AM(pfa)4 in buffer pH 9 was calculated as 5.806 ±0.001 (mean ± standard deviation).

Validity: The validity criteria and results are presented in the following table:

Table 20: Validity Criteria and Results, buffer pH 9

Peak	Parameter	Criterion	Found	Assessment
1	Range (Max – Min. log POW)	< 0.1	0.002	valid
	Value within Range of Ref. Items	0.304 - 2.364	1.757	valid

 

Conclusions:

The log Pow of the test item AM(pfa)4 was found being 6.0 (for pH 4), 5.7 (for pH 7) and 5.8 (for pH 9). Considering the low variation due to pH the mean average value of log Pow 5.8 is used for hazard and risk assessment.

Executive summary:

The study was performed using a HPLC with a C18 column. Seven reference items with different retention times and thiourea for the determination of the dead time were used to produce a calibration curve, since retention time on hydrophobic columns and Pow are correlated. The reference items were chosen based on the results of the (non-GLP) pre-test.

One vial was filled with the reference item mix and one vial with the test item solution. The vials were analysed using the HPLC with the program described. First one injection from the solvent blank methanol/buffer 75/25 (% v/v) was made. Then three injections were measured from the reference item mix in the corresponding eluent, three injections from the test item in the corresponding eluent and again three injections from the reference item mix.

For each reference item in the corresponding eluent, the capacity factor k was calculated from the retention time of thiourea and the retention time of the respective reference item.

A calibration function (log k versus log Pow, linear fit) was determined using the literature values for Pow of the reference items and the retention times in the six determinations.

The chromatogram of the test item AM(pfa)4 gave one peak with a retention time of 2.009 min (mean, for pH 4), 1.615 min (mean, for pH 7) and 1.757 min (mean, for pH 9).

With the respective calibration function log k versus log Pow, the corresponding log Pow could be calculated with 6.001 ±0.006 (for pH 4), 5.691 ±0.001 (for pH 7) 5.806 ±0.001 (for pH 9). Therefore, the log Pow of the test item AM(pfa)4 is stated as: 6.0 (for pH 4), 5.7 (for pH 7), 5.8 (for pH 9).

Considering the low variation depending on pH, the mean average of log Pow of 5.8 will be carried forward for hazard and risk assessment.

Description of key information

The log Pow of the test item AM(pfa)4 was found being 6.0 (for pH 4), 5.7 (for pH 7) and 5.8 (for pH 9). Considering the low variation due to pH the mean average value of log Pow 5.8 is used for hazard and risk assessment.

Key value for chemical safety assessment

Log Kow (Log Pow):

5.8

at the temperature of:

25 °C