Formulation, Optimization, and Characterization of Gastroretentive Floating Matrix Tablets of Baclofen Using Natural and Synthetic Polymers

The present study aimed to formulate, optimize, and characterize gastroretentive floating matrix tablets of Baclofen using natural and synthetic polymers to enhance gastric residence time and provide sustained drug release. Baclofen floating tablets were prepared by direct compression employing Hydroxypropyl Methylcellulose (HPMC K15M) as a synthetic polymer, Xanthan gum as a natural polymer, and Sodium bicarbonate as a gas-generating agent. A Box–Behnken Design (BBD) was utilized to optimize the formulation variables and evaluate their effects on Floating Lag Time (FLT), Total Floating Time (TFT), and cumulative drug release at 12 hours. Seventeen experimental formulations were developed and characterized. The optimized formulation (F18), comprising Baclofen (20 mg), HPMC K15M (100 mg), Xanthan gum (40 mg), and Sodium bicarbonate (30 mg), exhibited a desirability value of 0.963. The optimized batch showed rapid buoyancy with a floating lag time of 96.10 ± 1.4 s, prolonged floating duration of 12.78 ± 0.2 h, and sustained drug release of 88.83 ± 0.5% over 12 h. The formulation also demonstrated acceptable physicochemical properties, including hardness (5.8 ± 0.3 kg/cm²), friability (0.42%), drug content (99.34 ± 0.4%), and swelling index (228.46 ± 2.5%). ANOVA results confirmed the significant influence of HPMC K15M, Xanthan gum, and Sodium bicarbonate on the floating behavior and release characteristics of the tablets. The study established that a combination of natural and synthetic polymers can effectively produce gastroretentive floating matrix tablets with desirable buoyancy and sustained-release performance, thereby offering a promising strategy for improving the oral delivery of Baclofen.