Issue link: https://www.e-digitaleditions.com/i/701238
Tablets & Capsules July 2016 17 C excipients Properties of mucoadhesive polymers and their use in tablets and other dosage forms Elena Draganoiu Lubrizol Advanced Materials This article describes how several specialty polymers are used to formulate swallowable (peroral), buccal, and sublingual tablets, as well as topicals, suspensions, solutions, and mucoad- hesive products. arbopol polymers (carbomers), Noveon polycarbophil and Pemulen polymers are high molecular-weight poly- mers of acrylic acid chemically crosslinked with polyalkenyl alcohols or divinyl glycol [1, 2, 3]. These polymers are used in commercial formulations of different dosage forms for various applications, including peroral, chewable, buccal, and sublingual tablets; topicals (lotions, creams, gels); oral suspensions/solutions; oral-care prod- ucts; and mucoadhesive products. These polymers, when placed in contact with an aque- ous medium, hydrate and swell through hydrogen bond- ing or electrostatic repulsion (when neutralized). These mechanisms are the basis of the excipients' functionality in various pharmaceutical applications: • Bioadhesion in buccal, intestinal, ophthalmic, nasal, vaginal, and rectal applications. • Controlled-release from solid dosage forms. Carbopol polymers form gel matrices that control the release of active pharmaceutical ingredients (APIs) from tablets, lozenges, pastilles, and multiparticulate forms. The polymers are efficient. They have demonstrated slower release rates at lower concentrations than other com- mercially available excipients, enabling companies to reduce formulation costs and to make smaller tablets, which increases productivity and makes the tablets eas- ier to swallow.