In this study, polymeric beads of sodium alginate (NaAlg) and its blend with poly(vinyl alcohol) (PVA) were prepared by crosslinking with glutaraldehyde (2.5% v/v) and hydrochloric acid (3% v/v) for the release of naproxen sodium (NS). The prepared beads were characterized with Fourier transform infrared spectroscopy, and pictures of the beads were determined with an optic microscope. The release studies were carried out at three pH values (1.2, 6.8, 7.4) for 2 h. The effects of the preparation conditions, including the PVA/NaAlg (w/w) ratio, drug/polymer (w/w) ratio, and time of exposure to the crosslinker, on the release of NS were investigated for 10 h at 37 degrees C. The release of NS decreased with the PVA/NaAlg (w/w) ratio and drug/polymer ratio increasing. At the end of 10 h, the highest release of NS was found to be 84% for the 1/2 PVA/NaAlg (w/w) ratio. The swelling measurements of the beads supported the release results. The release kinetics were described with Fickian and non-Fickian approaches. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 2057-2065, 2009.