Registration Dossier

Administrative data

Endpoint:
water solubility
Type of information:
experimental study
Adequacy of study:
key study
Study period:
04 - 12 September
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 105 (Water Solubility)
Version / remarks:
1995
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.6 (Water Solubility)
Version / remarks:
Regulation (EC) No 440/2008
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
flask method

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
impurity
Test material form:
solid: particulate/powder
Details on test material:
Batch No.: 10004539
Storage at room temperature approx. 20°C

Results and discussion

Water solubility
Key result
Water solubility:
4.13 g/L
Conc. based on:
test mat. (dissolved fraction)
Temp.:
20 °C
pH:
>= 7 - <= 7.6
Details on results:
Preliminary test
This preliminary test indicated a water solubility of 1 to 10 g/L, as about 0.1 g were completely dissolved in 100 mL of ultra-pure water.

Main test
The results are given in the table in the next section. The individual results of the test vessels, which were deemed constant, were averaged and are given in mass per volume of solution. The test is satisfactory if the concentrations of at least the last two vessels do not differ by more than 15%.

Any other information on results incl. tables

HPLC determinations:

 Test vessel  pH  Analysed concentration A (g/L)   Analysed concentration B (g/L)   Analysed concentration C (g/L)  Mean (g/L)
 No. 1  7.0  3.94  4.14  4.11  4.06
 No. 2  7.1  4.17  4.06  3.74  3.99
 No. 3  7.3  4.25  4.43  4.37  4.35
 No. 4  7.6  4.09 4.12  4.12  4.11
       Overall Mean    4.13

The concentrations of the three vessels differed by 9% (validity criterion given by OECD is met).

Applicant's summary and conclusion

Conclusions:
The water solubility of Adenosine (CAS no. 58-61-7) was determined according to TG OECD 105.
The water solubility of the test item at 20°C was 4.13 g/L. The pH of the aqueous samples was 7.0 to 7.6.
Executive summary:

The water solubility of Adenosine (CAS no. 58-61-7) was determined according to TG OECD 105. Several test vessels containing ultra-pure water mixed with test item in great excess (initial amount of test item about 50 g per liter water), were incubated and stirred for different periods of time at about 30 °C (saturation phase), and then transferred to ca. 20 °C for 24 h (equilibration phase). Undissolved test item was subsequently separated by centrifugation. The concentration of test item in the clear aqueous phase was determined with HPLC.

The determined concentrations were as follows:

4.06 g/L after one day at 30 °C, followed by 24 h at 20 °C, pH 7.0 3.99 g/L after two days at 30 °C, followed by 24 h at 20 °C, pH 7.1 4.35 g/L after three days at 30 °C, followed by 24 h at 20 °C, pH 7.3 4.11 g/L after seven days at 30 °C, followed by 24 h at 20 °C, pH 7.6

As the determined concentration after three days of stirring at 30 °C and 24 h at about 20 °C increased in comparison with the results obtained after one and two days of stirring at 30 °C and 24 h at about 20 °C, the test was prolonged by using longer equilibration times. The concentration was also determined after seven days of stirring at about 30 °C and 24 h at about 20 °C.

The test vessels from all samplings were considered for the overall result, because no significant variation of the test item concentration was observed over the whole test duration.

The water solubility of Adenosine, calculated as the mean of all four test vessels, is 4.13 g/L at a pH of 7.0 to 7.6 and ca. 20 °C.

The validity criterion was fulfilled.