Related Experiment Video
Updated: Apr 5, 2026

Formation of Dispersible Taohong Siwu Tablets
Published on: February 3, 2023
Pectin/anhydrous dibasic calcium phosphate matrix tablets for in vitro controlled release of water-soluble drug
Pseidy Luz Mamani1, Roberto Ruiz-Caro2, María Dolores Veiga2
1Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain.
Abstract:
Different pectin/anhydrous dibasic calcium phosphate (ADCP) matrix tablets have been developed in order to obtain controlled release of a water-soluble drug (theophylline). Swelling, buoyancy and dissolution studies have been carried out in different aqueous media (demineralized water, progressive pH medium, simulated gastric fluid, simulated intestinal fluid and simulated colonic fluid), to characterize the matrix tablets. When the pectin/ADCP ratio was ≥0.26 (P1, P2, P3 and P4 tablets) a continuous swelling and low theophylline dissolution rate from the matrices were observed. So, pectin gel forming feature predominated over the ADCP properties, yielding pH-independent drug release behavior from these matrices. On the contrary, pectin/ADCP ratios ≤0.11 (P5 and P6 tablets) allowed to achieve drug dissolution pH dependent. Consequently, the suitable selection of the pectin/ADCP ratio will allow to tailor matrix tablets for controlled release of water-soluble drugs in a specific manner in the gastrointestinal tract.
Related Concept Videos
Modified-Release Drug Delivery Systems: Rate-Programmed I
Modified-Release Drug Delivery Systems: Rate-Programmed II
Factors Influencing Drug Absorption: Pharmaceutical Parameters
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
Oral Drug Delivery Systems: Continuous-Release Systems
Bioavailability Enhancement: Drug Stability Enhancement and GI Retention

