Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
24.08.2009 - 03.11.2009
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: According to guideline under GLP
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009
Report Date:
2009

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Deviations:
no
Principles of method if other than guideline:
Not relevant
GLP compliance:
yes (incl. certificate)
Type of method:
shake-flask method to: flask method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): R-Pantolactone
- Physical state: solid
- Analytical purity: 99.6%
- Stability under test conditions: stable
- Storage condition of test material: RT

Results and discussion

Partition coefficient
Type:
log Pow
Partition coefficient:
-0.46
Temp.:
22.5 °C
pH:
7.1

Any other information on results incl. tables

The n-Octanol / water partition coefficient (log Pow) of R-Pantolactone was determined by the

shake flask method to be log Pow = -0.46 at 22.5 °C, the Standard Deviation was +/- 0.05

The mean pH in the aqueous phase was 7.1.

Applicant's summary and conclusion

Conclusions:
During this study the Partition Coefficient (n-Octanol 1 Water) of R-Pantolactone was
determined and found to be log Pow = -0.46.
Executive summary:

The determination of the partition coefficient log Pow of R-Pantolactone was performed using

the flask shaking method as described in OECD guideline no. 107.

Due to the results of the preliminary test, the log Pow of R-Pantolactone was estimated to be

about <-0.67. Therefore, the flask shaking method was chosen to conduct the main test.

During the main study, three tests were carried out, each in duplicate, with volume ratios of both

solvents of 1 : 1, 2 : 1 and 1 : 2. After equilibration the concentration of the test item was determined

in both phases by HPLC.

The tabulated values represent rounded results, which were obtained by calculation using the

exact raw data. The log Pow at a mean pH value of 7.1 was calculated for each of the six vessels

and was found to be in the range of -0.41 to -0.54.

In order to check the analytical work, the mass balance for each vessel was calculated, too, and

the recovery of the test item was found to be in the range of 95% to 98%.

The correlation coefficient was 0.9997 (optimum 1,0000).

This reflects the linearity of the WPLC system within the calibration range of 1.649 pg/mL to

115.4 pg/mL of the test item.