The aim of this work was to design and evaluate effervescent floating gastro-retentive
drug delivery matrix tablets with sustained-release behavior using a binary mixture of
hydroxyethyl cellulose and sodium alginate. Pentoxifylline was used as a highly water-soluble,
short half-life model drug with a high density. The floating capacity, swelling, and drug release
behaviors of drug-loaded matrix tablets were evaluated in 0.1 N HCl (pH 1.2) at 37°C±0.5°C.
Release data were analyzed by fitting the power law model of Korsmeyer–Peppas. The effect
of different formulation variables was investigated, such as wet granulation, sodium bicarbonate
gas-forming agent level, and tablet hardness properties. Statistical analysis was applied
by paired sample t-test and one-way analysis of variance depending on the type of data to
determine significant effect of different parameters. All prepared tablets through wet granulation
showed acceptable physicochemical properties and their drug release profiles followed
non-Fickian diffusion. They could float on the surface of dissolution medium and sustain drug
release over 24 hours. Tablets prepared with 20% w/w sodium bicarbonate at 50–54 N hardness
were promising with respect to their floating lag time, floating duration, swelling ability, and
sustained drug release profile.
Keywords: floating tablets, sodium alginate, pentoxifylline, dissolution, swelling,
effervescent