The Influence of Polymers, Surfactants, and Other Excipients on Naproxen Sodium Release from Matrices Prepared and the Effect of These Additives on the Swelling Rate of the Tablet.

This study aimed to develop controlled-release matrix tablets of naproxen using the hydrophilic polymer sodium carboxymethylcellulose, investigate the impact of surfactants and other excipients on drug release and swelling rate, and determine the drug release mechanism. Naproxen matrices were formulated by the direct compression technique with different ratios of polymer sodium carboxymethylcellulose and other excipients. Drug release, swelling behavior, and release mechanism were assessed using an acidic dissolution medium. Drug release rate and mechanism were characterized by fitting the zero-order, first-order, Higuchi, and Korsmeyer-Peppas models. The amount of polymer sodium carboxymethylcellulose and other additives significantly affected drug release by regulating its rate according to polymer sodium carboxymethylcellulose ratios. Surfactants increased the drug release based on their solubility and wetting effects, independent of their charges. The release mechanism involved a combination of polymer diffusion and tablet erosion during dissolution. This study demonstrated that controlled release matrix tablets of naproxen can be effectively prepared by incorporating polymer sodium carboxymethylcellulose and other excipients via direct compression. The quantity of excipients can be adjusted to control the drug release rate from the matrices. The dissolution medium and the surfactants did not affect the matrix swelling, while the surfactants increased drug release via solubility and wetting effects rather than their charge. These findings have important implications for the design and development of controlled-release drug delivery systems.