2-[2-[4-[(2-cyanoethyl)methylamino]phenyl]vinyl]-1,3,3-trimethyl-3H-indolium dihydrogen phosphate

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:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

no

Type of method:

flask method

Water solubility:

ca. 51.82 g/L

Temp.:

20 °C

pH:

ca. 2.49

Remarks on result:

other: pH of satured solution

Details on results:

Preliminary solubility result
Reference samples and extract were first measured in the range 190 / 800 nm, so as to choose the right wavelength for quantitative measurements. Since absorbance of the test solution kept the same proportions along the UV and visible spectra, preliminary test result was considered for the final results calculations. Wavelength chosen was 514.00 nm.

Test results
Reference solutions were measured in the spectrophotometer in quantitative mode, thus generating a calibration curve. Calibration curve was smooth and linear at every concentration. Considering that preliminary test resulted in an absorbance keeping the same shape like the references, its value was considered for the 24 hours’ measurement (test 1).

Adjusting concentrations in proportion to the real weights, the folllowing results were obtained:

test 1 (24 hs)	50.36 g/l
test 2 (48 hs)	50.72 g/l
test 3 (96 hs)	57.37 g/l
average solubility	51.82 g/l
standard deviation	2.22
pH mother solution	2.99
pH satured solution	2.49

Conclusions:

At 20 °C and pH 2.49, the substance is very soluble in water, namely 51.82 g/l.

Executive summary:

Method

Shake flask method was used. A first preliminary solution was prepared, equilibrated at 30 °C for 24 h, then cooled to 20 °C for 24 hs. A second and third solutions were prepared and equilibrated at 30 °C for 48 and 96 hs, respectively. Then these solutions were cooled down to 20 °C for 24 hs. After centrifugation, analysis by UV-vis spectrophotometer was performed.

Results

Average water solubility was 51.82 g/l at 20 °C and pH 2.49 (satured solution).

Description of key information

Water solubility is 51.82 g/l at 20 °C and pH 2.49 (satured solution).

Key value for chemical safety assessment

Water solubility:

51.82 g/L

at the temperature of:

20 °C

Additional information

OECD guideline 105.