Diammonium decaborate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: CEMAS SOP CEM-3287

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

9.65 other: % (w/w)

Temp.:

20 °C

Remarks on result:

other: Calculated from the titration for boric oxide.

Preliminary Test:

Weight of test item used = 0.1005 g

Temperature of test = 20°C

Total Volume of distilled water added (mL)	0.1	0.5	1	2	10	100	>100
Was test item totally dissolved? (y/n)	No	No	Yes	N/A	N/A	N/A	N/A
Approximate solubility (g/L)	> 1000	1000 - 200	200 - 100	100 - 50	50 - 10	10 - 1	< 1

Based on the preliminary test the water solubility of the test item is from 100 – 200 g/L. The MSDS for the test item stated that the water solubility was 96 g/L which is within this range. The amount of test item required for 1 L of water would be 5 x 96 = 480 g and as this test is done in triplicate the total amount of test item is 480 x 3 = 1440 g. However based on the approximate amount of test item available the maximum weight of test item available for each replicate was 38.4 g. Based on the MSDS solubility of 96 g/L then the amount of water required for 38.4 g of test item would be:

(38.4/5)/96 x1000 = 80 mL

Approximately 38.4 g of test item was then accurately weighed into each of three flasks, 80 mL of distilled water was added to each and the flasks were then placed in a temperature controlled shaker at 30°C. Testing was then carried out.

Shake Flask Details:

Replicate Number	Weight of test item used (g)	Volume of distilled water added (mL)	Number of days shaking	pH of aqueous solution after shaking, 24 hours in 20°C water bath and centrifugation and filtration
Replicate 1	38.3957	80	1	7.16
Replicate 2	38.4061	80	2	7.14
Replicate 3	38.3956	80	3	7.26

After removal from the shaker the test item solutions were placed in a water bath, set at 20°C, for 24 hours prior to centrifugation, filtration and analysis. However due to a delay in the analysis the centrifuged and filtered aqueous test item solutions were placed back in the 20°C water bath and kept at temperature until analysed.

Water Solubility Solution Analysis Results:

Replicate Number	Volume of aqueous test item solution taken (mL)	Weight of aqueous test item solution taken (g)	Volume of 0.5N hydrochloric acid added (mL)	Volume of 0.5N sodium hydroxide added at first titration end point (mL)	Ammonium oxide content (% w/w)	Ammonium pentaborate content (% w/w)	Volume of 0.5N sodium hydroxide added at second end point (after addition of mannitol) (mL)	Boric oxide content (% w/w)	Ammonium pentaborate content (% w/w)
Replicate 1	10	10.4139	25	17.30	0.93	9.67	37.00	6.20	9.70
Replicate 2	10	10.4123	25	17.40	0.91	9.54	37.10	6.22	9.73
Replicate 3	10	10.3907	25	17.60	0.89	9.30	36.25	6.09	9.53
				Mean =	0.91	9.50	Mean =	6.17	9.65
				SD =	0.018	0.19	SD =	0.070	0.11
				%RSD =	1.99	1.99	%RSD =	1.14	1.14

Conclusions:

Interpretation of results: very soluble (> 10000 mg/L)
Mean water solubility for the ammonium pentaborate test item is 9.65 % w/w.

Executive summary:

The test item was analysed for water solubility in a GLP study following EU Method A.6. The results show that the mean water solubility for the ammonium pentaborate test item is 9.65 % w/w (calculated from the titration for boric oxide).

Description of key information

The test item was analysed for water solubility in a GLP study following EU Method A.6. The results show that the mean water solubility for the ammonium pentaborate test item is 9.65 % w/w (calculated from the titration for boric oxide).