Rheological Behavior of a New Mucoadhesive Oral Formulation Based on Sodium Chondroitin Sulfate, Xyloglucan and Glycerol

Abstract

Background: The study aimed at assessing the mucoadhesive properties and the barrier effect of a formulation, labelled as AL2106, containing sodium chondroitin sulfate (ChS), xyloglucan from tamarind seed extract, and glycerol, by evaluating the capacity to adhere to a layer of mucin, the rheological synergism and the barrier effect in comparison to the marketed Esoxx One medical device. AL2106 is a medical device distributed by Alfasigma SpA, Italy with REF FTP57 (Manufacturer: Labomar SpA); it is analogous to Esoxx One medical device: the two products are drinkable solutions that, after swallowing, adhere to the esophageal mucosa, protecting it from the corrosive effect of the gastric acid reflux. AL2106 has been conceived to be better performing in terms of duration of the barrier effect compared to Esoxx One. Methods: The mucoadhesive properties, rheological behavior, buffering capacity against acidity, and film-forming ability with the resultant protecting effect on esophagus mucosa (caffeine permeation test) was compared between the two products. Results: The mucoadhesivity of the formulations was shown in vitro: both remained adherent to a mucin layer, also when the support was rotated by 90°, and when the film layer was washed with water, intended to simulate the washout due to swallowing. AL2106 showed a good buffering efficacy, being able to absorb at least 50% of its weight of 0.03 M HCl while maintaining the pH above 4. The film-forming effect and barrier properties of AL2106 and Esoxx One were confirmed by an in vitro study on reconstructed human esophageal epithelium. A greater film-forming efficacy of AL2106, lasting for at least 5 h, than Esoxx One was observed. Noteworthy, the barrier function of esophageal tissues was shown to be preserved after the application of both formulations. Conclusions: The combination of ChS with the mucoadhesive glycerol−xyloglucan complex and other excipients, which contribute to the barrier effect and to mucoadhesion, contained in AL2106, allowed a longer-lasting protective effect than Esoxx One, proving its effectivity and safety for oral use.

Exploring a Novel Fasudil-Phospholipid Complex Formulated as Liposomal Thermosensitive in situ Gel for Glaucoma

“…Such a rheological synergy implies an intimate interaction with mucin proposing formulation capability of mucoadhesion to ocular tissues. 39 The present results demonstrated that although a positive rheological synergism occurred for all tested formulations, the highest Δη % was observed with Fas/PL-Lipo P407/HPMC gel (Figure 5B). The enhanced mucoadhesion observed for Fas/PL-Lipo P407/HPMC gel compared to Fas/PL-Lipo P407 gel indicates synergistic effect of the combination of P407 and HPMC on extending precorneal residence time which may be contributed to the weak chemical bonds formed between wetted and swelled mucoadhesive HPMC chains and mucin particles introducing prolonged adhesion of the hydrogel at the mucosal surface.…”

An Evaluation of the Efficacy and Safety of TAMIXAM®, Based on Hyaluronic Acid and Tamarind Seed Extract, for Esophageal Mucosal Protection from Acid Insult

“…To uphold the uniqueness of our research on efficacy assessment, it has been crucial to compare our findings with studies involving HA by itself and in combination with other compounds. Numerous investigations have illustrated the favorable impact of HA and chondroitin sulfate on mucosal protection [25]. Nonetheless, TAMIXAM ® distinguishes itself through its exclusive composition, encompassing both HA and TSX.…”

A Review of Xyloglucan: Self-Aggregation, Hydrogel Formation, Mucoadhesion and Uses in Medical Devices

“…Rheology is thus used as an experimental tool for the evaluation of mucoadhesivity in new formulations. In one recent example [74], the mucoadhesive properties of a formulation containing sodium chondroitin sulfate, XG and glycerol were evaluated in vitro by determining the rheological synergy of the mixture, as well as other techniques, such as the direct measurement of adhesion forces.…”