Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Aug 2013
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: According to OECD guideline under GLP
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2013
Report Date:
2013

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
Deviations:
no
Principles of method if other than guideline:
not relevant
GLP compliance:
yes
Type of method:
HPLC method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder

Study design

Analytical method:
high-performance liquid chromatography

Results and discussion

Partition coefficient
Type:
log Pow
Partition coefficient:
4
Temp.:
25 °C
Remarks on result:
other: ±0.01 (95 % confidence interval)
Details on results:
The capacity factors k’ and log Pow for K-36 were calculated based on the calibration data obtained with the reference substances.

Any other information on results incl. tables

Table 1: Measured and calculated mean data of K-36

Retention Time         log k´        log pow        Pow

Mean                     8.56                       0.724       4.03           10656

Applicant's summary and conclusion

Conclusions:
The estimated log Pow is 4.0±0.01 (95 % confidence interval).
Executive summary:

The purpose of this study was to determine the partition coefficient of K-36. The study has been performed in accordance with the OECD test guideline No.117 (2004).

The partition coefficient (P) is defined as the ratio of the equilibrium concentrations of a dissolved substance in a two-phase system. In this case there is a partitioning between the mobile solvent phase and the hydrocarbon stationary phase. This enables the relationship between the retention time on a reverse-phase column and the n-octanol/water partition coefficient to be established.

Six chemicals for which log Pow has been reported were used as reference substances to calibrate the elution time in units of log k’.

Reference substances were dissolved in acetonitrile. Concentration of these stock solutions was about 1 mg/ml. The stock solutions were diluted with the eluent by 100 fold. 100 μg/ml test item stock solution was prepared in DMSO and diluted tenfold with DMSO.

The three calibration series and three test item series were measured alternately. The partition coefficient Pow was determined based on a calibration curve using 6 reference substances.

The capacity factors k’ were calculated from the dead time and retention times of the reference substances. The log k’ data of the reference substances were plotted against their log Pow values. The equation of the curve fitted to the calibration points is as follows:

log k` = 0.302 × log Pow - 0.494 (Rsq = 0.991).

The capacity factors k’ and log Pow for K-36 were calculated based on the calibration data obtained with the reference substances.

The estimated log Pow: 4.0±0.01 (95 % confidence interval).