Naphthalene-2,6-dicarboxylic acid

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 March 2018 - 1 June 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and batch No.of test material: Sigma Aldrich, lot No. 15021MU
- Expiration date of the lot: 30 Jan 2019
- Purity test date:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Ambient

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

- Sampling intervals for the parent/transformation products: 0 and 5 days (50ºC, pH 4, 7 and 9)
- Sampling method: 2 mL aliquot diluted with 2 ml acetonitrile
- Sampling intervals/times for pH measurements: Initial test solutions and final sampling
- Sampling intervals/times for sterility check: Initial test solutions and final sampling
- Sample storage conditions before analysis: Samples stored at <-20 ºC and analysed within 2 days of extraction.

Buffers:

- pH: 4
- Type and final molarity of buffer: Sodium acetate 0.01 M
- Composition of buffer: Sodium acetate trihydrate dissolved in deionised water (ca 900 mL)

- pH: 7
- Type and final molarity of buffer: Tris (hydroxymethyl) aminomethane hydrochloride, 0.01 M
- Composition of buffer: Tris (hydroxymethyl) aminomethane hydrochloride dissolved in deionised water

- pH: 9
- Type and final molarity of buffer: Di-sodium tetraborate, 0.01 M
- Composition of buffer: Di-sodium tetraborate decahydrate dissolved in deionised water

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: Screw capped straight sided amber glass tubes of approximately 8 mL capacity
- Sterilisation method: Filtration of the solutions through a 0.2µm bottle top filter. Glasware was sterilised using an autoclav. Vessel caps and pipette tips were sterilitzed with ethanol:water 70:30 (v/v)
- Lighting: dark
- Measures to exclude oxygen: Bubbling with nitrogen
TEST MEDIUM
- Kind and purity of water: deionised water
- Preparation of test medium: Buffer salts were dissolved in deionized water
OTHER TEST CONDITIONS
- Adjustment of pH: Buffers were adjusted with acetic acid (pH 4), sodium hydroxide solution (pH 7) and HCl (pH9), respectively

Duration:

5 d

pH:

4

Temp.:

50 °C

Initial conc. measured:

0.03 µg/L

Duration:

5 d

pH:

7

Temp.:

50 °C

Initial conc. measured:

0.03 µg/L

Duration:

5 d

pH:

9

Temp.:

50 °C

Initial conc. measured:

0.03 µg/L

Number of replicates:

2

Positive controls:

yes

Remarks:

Agar plates to confirm sterility

Negative controls:

no

Preliminary study:

No hydrolytical degradation was observed in the Tier 1 study. Therefore, a Tier 2 study was not conducted

Transformation products:

no

Key result

Remarks on result:

hydrolytically stable based on preliminary test

Details on results:

TEST CONDITIONS
- pH, sterility, temperature, and other experimental conditions maintained throughout the study: Yes

TRANSFORMATION PRODUCTS
No degradation and hence no transformation products were observed at any of the tested pH values.

Validity criteria fulfilled:

yes

Conclusions:

2,6-Naphthalene dicarboxylic acid is hydrolytically stable under the conditions of the test.

Description of key information

2,6 -Naphthalene dicarboxylic acid is hydrolytically stable.