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Updated: Jan 31, 2026

Lumican Extraction from Amniotic Membrane and Determination of its Storage Temperature
Published on: October 14, 2022
Permeability of the amniotic membranes to the natural vanilla molecule
Carlos N López Ramón Y Cajal1, Laura Gonzalez Rodriguez1
1Service of Obstetrics and Gynecology, Álvaro Cunqueiro Hospital, Vigo,Pontevedra, Spain.
Purpose: We studied natural vanilla permeability through amniotic membranes.Methods: We studied natural vanilla permeability through amniotic membranes obtained from 45 spontaneous normal deliveries at term. The ferric chloride test (FeCL3) was used to determine the presence or absence of phenols in a given sample. Vanilla is a polyphenol so it gives a reaction to FeCL3 with an intense color change. The diffusion of the vanilla was checked by dropping ferric chloride solution on the gauze once the membranes are lifted with care to avoid contamination. If vanilla has passed through the membranes the distilled water papers would change from an initial ferric yellow in the drops toward a marked gray/greenish color on the papers (positive test).Results: In all cases, the swabs were stained, all the membranes in both directions were permeable to the whole vanilla molecule.Conclusions: This experiment allows us to reevaluate the importance of molecular diffusion through the amniotic membranes with no placental metabolism existing between maternal and fetal environment.
Purpose: We studied natural vanilla permeability through amniotic membranes.Methods: We studied natural vanilla permeability through amniotic membranes obtained from 45 spontaneous normal deliveries at term. The ferric chloride test (FeCL3) was used to determine the presence or absence of phenols in a given sample. Vanilla is a polyphenol so it gives a reaction to FeCL3 with an intense color change. The diffusion of the vanilla was checked by dropping ferric chloride solution on the gauze once the membranes are lifted with care to avoid contamination. If vanilla has passed through the membranes the distilled water papers would change from an initial ferric yellow in the drops toward a marked gray/greenish color on the papers (positive test).Results: In all cases, the swabs were stained, all the membranes in both directions were permeable to the whole vanilla molecule.Conclusions: This experiment allows us to reevaluate the importance of molecular diffusion through the amniotic membranes with no placental metabolism existing between maternal and fetal environment.
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