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Abstract

Water-soluble polymers were synthesized from dextran and polyacrylic acid and their ocular mucoadhesion was evaluated. One series had polyacrylic acid grafted onto the polysaccharide backbone of dextran, and another series had dextran grafted onto the polyacrylic acid backbone. Mucoadhesion of these copolymers was investigated using a tensile apparatus and compared with that of polyacrylic acid/dextran mixtures prepared in different proportions. Whatever the copolymer structure, no synergistic effects were seen and mucoadhesion was not markedly increased compared to dextran. The adhesion of copolymers was the same as that of mixtures having a similar polyacrylic acid content and was always less than that of polyacrylic acid alone. Formation of an interpolymer complex occurred at concentrations up to 60% polyacrylic acid, and only above this value did bioadhesion increase above that of dextran. When this complex was dissociated by neutralization of the carboxyl groups of polyacrylic acid, the mucoadhesion of the copolymers and the mixtures was improved. These experiments demonstrated that copolymers and mixtures of dextran and polyacrylic acid did not produce polymers with improved ocular mucoadhesion.

Interpolymer Complexes of Water‐Soluble Nonionic Polysaccharides with Polycarboxylic Acids and Their Applications

“…Water‐soluble polymers were synthesized from dextran and poly(acrylic acid) and their ocular mucoadhesion was evaluated by Thermes et al87 They used poly(acrylic acid) grafted onto the polysaccharide backbone of dextran and dextran grafted onto a PAA backbone. Mucoadhesion of these grafted copolymers was studied in comparison with PAA/dextran mixtures prepared at different proportions.…”

Development of a “Continuous-Flow Adhesion Cell” for the Assessment of Hydrogel Adhesion

“…1). The different methods used to predict bioadhesion are mainly adhesion strength tests (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12), perfusion techniques (1,13,14), and rheological tests (1). Among them, only perfusion techniques may assess the duration of adhesion, and they appear as a more realistic measurement of adhesion performances since adhesion strength and rheological tests are indirect methods for bioadhesion evaluation.…”