Controlled Release

Artificial intelligence (AI) has emerged as a transformative tool in pharmacology and pharmaceutics, enabling accelerated drug discovery, formulation optimization, and clinical translation. Machine learning, deep learning, and predictive modeling improve target identification, lead optimization, and personalized therapy. AI-driven platforms facilitate high-throughput screening, pharmacokinetic/pharmacodynamic (PK/PD) modeling, and nanocarrier design, reducing time, cost, and attrition rates. This review highlights the applications of AI across the drug development pipeline, from molecular discovery to regulatory submission, and discusses challenges, ethical considerations, and future perspectives in precision pharmacotherapy.

The present study compares three colon-targeted drug delivery systems; Eudragit S100-coated polymeric tablets, PLGA nanoparticles, and alginate hydrogel microspheres, developed for the controlled release of 5-Fluorouracil (5-FU). Each formulation was prepared and optimized using distinct carriers and evaluated under simulated gastrointestinal (GI) conditions to assess their physicochemical characteristics, release behaviour, and stability. The formulations were characterized for particle size, surface charge, encapsulation efficiency, and swelling index. Morphological analysis confirmed smooth coating in polymeric tablets, spherical uniformity in nanoparticles, and a porous structure in hydrogels. In vitro dissolution studies revealed minimal drug release in gastric conditions (≤2% at pH 1.2) and sustained release at colonic pH (7.4). PLGA nanoparticles showed the most controlled release profile, achieving 92.1 ± 2.4% cumulative release at 24 hours, compared with 100.0 ± 3.1% for polymeric tablets and 85.4 ± 2.1% for hydrogels. Kinetic modeling indicated that all systems followed diffusion-dominated release, with nanoparticles best fitting the Higuchi model (R² = 0.981). Stability studies confirmed nanoparticle integrity under prolonged acidic and neutral exposure, while hydrogels exhibited partial deformation. Overall performance analysis identified PLGA nanoparticles as the most efficient system, demonstrating superior acid resistance, encapsulation efficiency, and colon-specific release. These findings suggest that nanoparticle-based carriers offer significant potential for achieving predictable, site-specific, and sustained drug delivery to the colon.

Animal-based testing is important for understanding the performance, mechanism, and translational capacities of floating tablets and in-vitro testing for stomach retention, which is the focus of the current review.  With a limited window for absorption in the upper gastrointestinal tract, drug delivery systems (FDDS) are designed to improve the residence time, bioavailability, and controlled release of medications.  The recipes that employed gas-producing agents like sodium bicarbonate and citric acid, as well as hydrophilic polymers like HPMC, carbopol, and sodium alginate, demonstrated exceptional floating properties with a lag time of less than 12 hours. In vitro research studies showed sustained release profiles along the zero-order or non-Fickian kinetics, whereas in vivo testing in albino rats and rabbits showed long gastric retention and better pharmacokinetic results. Gastric safety and biocompatibility was confirmed by histopathological assessments. Direct compression was determined to have the best formulation through comparative analysis based on stable and efficient formulations compared to wet granulation. All in all, animal tests will be a critical preclinical base to determine optimal proportions of polymers, buoyancy, and release characteristics which will make floating pills safe and effective when applied to the clinical setting.

This review will concentrate on the use of natural polymers, such as xanthan gum, tamarind gum, fenugreek gum, and chitosan as part of nifedipine sustained-release matrix systems: the animal-based research will be emphasized. The swelling, gel formation, viscosity, and mucoadhesive characteristics of natural polymers are effective in drug release control to provide a long-lasting and controlled therapeutic plasma concentration. The polymers have potential to increase bioavailability, stability, and safety which have been shown through different formulation strategies such as direct compression, solvent evaporation, and extrusion-spheronization as well as pharmacokinetic assessment in rats and rabbits, in vivo. Although they have these benefits, which include biocompatibility, biodegradability, cost-effectiveness, and sustainability, the issues of batch variability, mechanical constraints, and regulatory barriers are still present. The next generation of such polymer-based systems needs to focus on standardization, mechanistic knowledge, long-term stability and regulatory compatibility to maximize the clinical utility of these future systems.