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A novel natural GRAS-grade enteric coating for pharmaceutical and nutraceutical products

Research output: Contribution to journalArticle

Mouhamad Khoder, Verena Schropp, Susanne Zeitler, Beatriz Pereira, Rober Habashy, Paul G Royall, Julie Tzu-Wen Wang, Mohamed A Alhnan

Original languageEnglish
Article number119392
Early online date4 May 2020
Accepted/In press28 Apr 2020
E-pub ahead of print4 May 2020
Published30 Jun 2020

Bibliographical note

Copyright © 2020 Elsevier B.V. All rights reserved.

King's Authors


In this study, enteric coatings based exclusively on naturally occurring ingredients were reported. Alginate (Alg) and pectin (Pec) blends with or without naturally occurring glyceride, glycerol monostearate (GMS), were initially used to produce solvent-casted films. Incorporating GMS in the natural polymeric films significantly enhanced the acid-resistance properties in gastric medium. Theophylline tablets coated with Alg-Pec blends without GMS disintegrated shortly after incubation in gastric medium (pH 1.2), leading to a premature and complete release of theophylline. Interestingly, tablets coated with Alg-Pec blends that contain the natural glyceride (GMS) resisted the gastric environment for 2 h with minimal drug release (<5%) and disintegrated rapidly following introduction to the intestinal medium, allowing a fast and complete drug release. Furthermore, the coating system proved to be stable for six months under accelerated conditions. These findings are particularly appealing to nutraceutical industry as they provide the foundation to produce naturally-occurring GRAS based enteric coatings.

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