Dissolution of abietic acid in water by the solid dispersion method using methylcellulose analogs

Abstract Solid dispersion materials of abietic acid (ABA) were prepared with methylcellulose (MC), hydroxypropyl methylcellulose (HPMC), and sodium carboxymethylcellulose (CMC-Na) using a conventional solvent evaporation method. In these materials, ABA was incorporated in an amorphous form. During dissolution tests, ABA from ABA/MC and ABA/HPMC solid dispersion materials initially rapidly dissolved, followed by a decrease in the dissolution rate before eventually plateauing. The dissolution of ABA from ABA/CMC-Na solid dispersion materials was similar, although it increased slightly with an increased shaking time over a long period. ABA from ABA/MC solid dispersion materials exhibited a higher dissolution rate compared with ABA from both ABA/HPMC and ABA/CMC-Na solid dispersion materials. The amount of undissolved material from ABA/cellulose derivative solid dispersion materials was lower compared with ABA/cellulose nanofiber and ABA/TEMPO-oxidized cellulose nanofiber solid dispersion materials. In addition, both ABA/MC and ABA/HPMC solid dispersion materials exhibited good growth-inhibitive effects against Trametes versicolor , a representative of white-rot fungus, compared with ABA/CMC-Na, ABA/cellulose nanofiber and ABA/TEMPO-oxidized cellulose nanofiber solid dispersion materials. Consequently, MC proved to be the most effective water-soluble carrier for ABA in water among the cellulose derivatives tested.