Myo-Inositol, hexakis(dihydrogen phosphate), dodecasodium salt

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19th Oct. 2017 - 08th Jan..2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

yes

Remarks:

Instead of 24 h of equilibration of the saturated solutions at the test temperature after incubation at 30°C for 24 h, 48 h, and 72 h according to OECD 105 Guideline, in this study we equilibrated for 5 h at the test temperature (24°C).

GLP compliance:

no

Type of method:

flask method

Specific details on test material used for the study:

- Batch No.: 487478
- Expiry Date: January 2020

Key result

Water solubility:

247.6 g/L

Conc. based on:

test mat.

Remarks:

mean value of the three incubation times (flasks)

Loading of aqueous phase:

1 000 g/L

Incubation duration:

>= 24 - <= 72 h

Temp.:

24 °C

pH:

>= 10.7 - <= 10.93

Preliminary test

The results of the preliminary test indicates that the approximate water solubility of the test item lies between 200 and 1000 g/l at a temperature of 24°C.

Main Test (flask method)

Two seperate experiments (runs) were conducted:

1^strun:

Incubation time [h]	Mass Test item (df PA-12)t0in g	Mass (water)t0in g	pHsolution (pH paper measurement)	Mass of “clear aqueous solution” after filtration in g	Mass of “clear aqueous solution” after evaporation in g
24	10.00	10.01	11-12	1.30	0.28
48	10.00	10.00	11-12	1.26	0.25
72	10.00	10.01	11-12	0.67	0.12

 

Incubation time [h]	Loss on drying (19.27 %) corrected mass of the “evaporated clear aqueous solution” in g	Calculated Test Item concentration in %	Calculated Test Item concentration (g/l)
24	0.334	25.69	256.89
48	0.298	23.66	236.65
72	0.143	21.36	213.62

 

Average Water solubility: 235.72 g/l

Relative Standard deviation: 9.18 %

%-Difference between Incubation times:

24 h vs. 48 h:    7.88 %

24 h vs. 72 h:    16.84 %

48 h vs. 72 h:    9.73 %

 

OECD 105 Guideline states that if the concentrations measured in at least the two last vessels do not differ by more than 15% the test result is satisfactory. Strictly speaking, this criterion is fulfilled in that at least the results of the two last vessels (48 h and 72 h) did not differ by more than 15 % (9.73 %). However, because of the relatively large difference between the first and the last vessel (24 h vs. 72 h) the main experiment was repeated in a 2nd run.

2^ndrun:

Incubation time [h]	Mass of Test item (df PA-12)t0in g	Mass of (water)t0in g	pHsolution (pH meter)	Mass of “clear aqueous solution” after filtration in g	Mass of “clear aqueous solution” after evaporation in g
24	10.01	10.02	10.70	1.77	0.35
48	10.00	10.04	10.93	1.61	0.35
72	10.01	10.00	10.92	1.83	0.38

 

Incubation time [h]	Loss on drying (19,27%) corrected mass of the “evaporated clear aqueous solution” in g	Calculated Test Item concentration in %	Calculated Test Item concentration (g/l)
24	0.417	23.559	235.59
48	0.417	25.901	259.01
72	0.453	24.754	247.54

The pH value of the sample solution was 10.7 (10.93, 10.92) after 24 (48, 72) hours of incubation.

Average Water solubility:247.6 g/l

Relative Standard deviation:4.73 %

%-Difference between Incubation times:

24 h vs. 48 h:    9.04 %

24 h vs. 72 h:    4.77 %

48 h vs. 72 h:    4.48 %

The results determined for the three flasks of different incubation times (24h, 38h, 72h) did not deviate by more than 15%. Therefore, the criterion of the OECD 105 Guideline is fulfilled.

The Water solubility of the test item at 24°C is 247.6 g/l.

Conclusions:

The Water solubility of the test item at 24°C is 247.6 g/l (OECD 105, flask method).

Executive summary:

The results determined for the three flasks of different incubation times (24h, 38h, 72h) did not deviate by more than 15%. Therefore, the criterion of the OECD 105 Guideline is fulfilled.

The Water solubility of the test item at 24°C is 247.6 g/l.

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Remarks:

published literature (J. Chem. Thermodynamics 42 (2010) 1393–1399)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Qualifier:

no guideline followed

Principles of method if other than guideline:

Saturated solutions of the test item were prepared by adding the test item in pure water up to the formation of an insoluble compound. The solutions were stirred at T = 298.15 K and after 24 h, the concentration of the liquid phase stays constant. Preliminary
tests established that longer stirring times were unnecessary. A volume of 25 mL of the filtered solution (by 0.45 lm Albet cellulose acetate filters) containing also a suitable amount of HCl, was titrated with standard NaOH (potentiometric measurement). To avoid systematic errors, independent experiments were performed at least three times.

GLP compliance:

no

Specific details on test material used for the study:

The test item (Dodecasodium phytate) solutions were prepared by weighing the pure salt Na12Phy, and its purity was checked potentiometrically by acidimetric titrations. All chemicals were of the purest available grade, and were purchased from Sigma–Aldrich (and its various brands). All solutions were prepared with analytical grade water (R = 18MX _ cm_1) using grade A glassware.

Water solubility:

0.3 other: mol/L

Conc. based on:

test mat.

Remarks:

St. deviation = 0.006

Incubation duration:

24 h

Temp.:

298.15 K

Conclusions:

Total solubility of the test item (Na12Phy) in pure water: 0.300 ± 0.006 mol • L-1

Executive summary:

Total solubility of the test item (Na12Phy) in pure water: 0.300 ± 0.006 mol/L.

      

Description of key information

The Water solubility of the test item at 24°C is 247.6 g/l (OECD 105, flask method).

Key value for chemical safety assessment

Water solubility:

247.6 g/L

at the temperature of:

24 °C

Additional information

The experimental study according to OECD 105 guideline resulted in a water solubility of 247.6 g/L at 24°C.

The Supporting data (published literature) resulted in a water solubilitly of 0.300 ± 0.006 mol/L at 25°C (298.15 K). This equals a water solubility of 277.1 g/L, considering the molecular weight of 923.81 g/mol for the test item (CAS 17211 -15 -3).