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Note for Guidance for Food Contact Materials
Page 61 of 126
2 PRINCIPLE
The test substance (monomer or additive) is dissolved in an appropriate solvent. An
aliquot of the solution is transferred to the digestive fluid simulant, which is maintained at
37C with continual agitation. After a specified time period the concentrations of both
parent constituent and hydrolysis products are determined in the simulant, whereupon
percentage hydrolysis is calculated.

3 REAGENTS
NOTE: All reagents should be of recognised analytical quality unless otherwise specified.

3.1 Chemicals

3.1.1 Water, distilled or deionised
3.1.2 Sodium bicarbonate (NaHCO
3
)
3.1.3 Sodium
chloride
(NaCl)
3.1.4 Sodium
taurocholate?
3.1.5 Potassium carbonate (K
2
CO
3
)
3.1.6 Sodium hydroxide standard solution, 0.2 M
3.1.7 Hydrochloric acid standard solutions, 2 M and 0.1 M
3.1.8 Potassium dihydrogen orthophosphate (KH
2
PO
4
)
3.1.9 Porcine pancreatin extract, activity equivalent to 8x SUP specification
3.1.10 Dispersing solvents, one of:
- acetonitrile
- N,N-dimethylacetamide
- 1,4-dioxane
- ethanol
- methanol
- propan-2-ol
- tetrahydrofuran
- water

3.2
Digestive fluid simulants

3.2.1 Saliva
simulant:
Dissolve 4.2 g of sodium bicarbonate (NaHCO
3
), 0.5 g of sodium chloride (NaCl) and 0.2
g of potassium carbonate (K
2
C0
3
) in 1 litre of water. The pH of the solution should be
approximately 9.

3.2.2 Gastric-juice
simulant:
Dilute 0.1 M hydrochloric acid standard solution to a concentration of 0.07 M. The pH of
the solution should be 1.2 + 0.1.

3.2.3 Intestinal-fluid
simulant:
NOTE: Care should be taken to ensure that the simulant is prepared in the order given.
Dissolve 6.8 g of potassium dihydrogen orthophosphate (KH
2
PO
4
) in 250 ml of water,
transfer to a 1 L volumetric flask and add 190 ml of 0.2 M sodium hydroxide (NaOH).
Add 400 ml of water and shake briefly to mix. Weigh 10.0 g of pancreatin extract into a
250 ml beaker. Add a little water, and stir to make a stiff, homogenous paste. Gradually
dilute the paste with small portions of water, stirring well after each dilution, to give
approximately 150 ml of a lump-free solution. Transfer the solution to the volumetric
flask, rinsing the beaker and funnel with water. Add 0.5 g of sodium taurocholate, gently