Related Experiment Video
Updated: Aug 6, 2026
09:59
Coherent anti-Stokes Raman Scattering (CARS) Microscopy Visualizes Pharmaceutical Tablets During Dissolution
Published on: July 4, 2014
Effect of hydrodynamic environment on tablet dissolution using flow-through dissolution apparatus
1School of Pharmacy, University of Puerto Rico, San Juan.
Puerto Rico Health Sciences Journal
|August 4, 2006
Summary
Drug dissolution rate is influenced by hydrodynamic conditions like flow rate and apparatus type. An equation was developed to predict drug release from conventional tablets.
Area of Science:
- Pharmaceutical Sciences
- Physical Chemistry
- Chemical Engineering
Background:
- Understanding drug dissolution is crucial for predicting in vivo performance.
- Hydrodynamic conditions significantly impact drug release from solid dosage forms.
- Existing models may not fully capture the influence of fluid dynamics on dissolution.
Purpose of the Study:
- Investigate principles of drug dissolution.
- Study drug release phenomena in laminar flow.
- Determine the effect of hydrodynamic conditions on drug dissolution to predict release from solid dosage forms.
Main Methods:
- Formulated theophylline (Class I) and naproxen (Class II) into conventional tablets and hydroxypropylmethylcellulose (HPMC) matrices.
- Tested dissolution using USP II and IV apparatus with varying cell diameters, flow rates, and tablet positions.
- Developed a predictive equation for drug dissolution from conventional tablets.
Main Results:
- Increased flow rate enhanced drug release.
- Smaller cell diameter and horizontal tablet position in USP IV apparatus led to faster dissolution.
- Hydrodynamic conditions did not affect HPMC matrix tablet dissolution, indicating matrix control.
- Established a predictive equation: Sh=-21.36+10.58Re(1/2) (R²=0.98) for conventional tablets.
Conclusions:
- Hydrodynamic conditions and dissolution apparatus type influence dissolution rate, mass transfer, and film thickness.
- Drug release from HPMC matrices is primarily matrix-controlled, independent of hydrodynamics.
- The developed equation provides a tool for predicting drug dissolution from conventional tablets.
Related Concept Videos
01:13In Vitro Drug Dissolution: Compendial Testing Models I
Compendial dissolution methods are standardized procedures defined by pharmacopeias to evaluate the rate at which a drug dissolves in a specific medium. These methods ensure batch-to-batch consistency, enable quality control, and support the prediction of drug bioavailability. They are critical for both immediate and modified-release drug products.The apparatuses used for dissolution testing differ in their design and mechanical function, but all aim to simulate the physiological environment of...
01:09In Vitro Drug Dissolution: Compendial Testing Models II
Various dissolution methods are utilized to assess a drug’s dissolution rate, including the flow-through cell, paddle-over-disk, cylinder, and reciprocating disk methods.The flow-through cell apparatus (USP (United States Pharmacopeia) method 4) comprises a reservoir for the dissolution medium and a pump that propels the medium through the cell containing the test sample. This method is crucial for assessing modified-release dosage forms with minimally soluble active ingredients, maintaining...
01:15Theories of Dissolution: Diffusion Layer Model
Dissolution, the process by which drug particles dissolve in a solvent, is explained by the diffusion layer model, a theoretical framework that simulates the absorption of oral drugs and allows us to analyze experimental data.
This process starts with a thin layer, saturated with the drug, forming at the interface between the solid and liquid. The solute then diffuses from this layer into the main solution. The Noyes-Whitney equation suggests that the rate of dissolution relies on the diffusion...
This process starts with a thin layer, saturated with the drug, forming at the interface between the solid and liquid. The solute then diffuses from this layer into the main solution. The Noyes-Whitney equation suggests that the rate of dissolution relies on the diffusion...
01:17In Vitro Drug Dissolution: Alternative Methods
Alternative drug dissolution methods include the rotating bottle, intrinsic dissolution test, peristalsis, and the Franz diffusion cell method. The rotating bottle method involves meticulously rotating tightly capped controlled-release beads in a temperature-controlled bath. Periodic decanting of samples allows for residue assay, followed by refilling with fresh medium and testing at various pH levels to emulate the gastrointestinal tract conditions.In contrast, the intrinsic dissolution test...
01:28Factors Influencing Drug Absorption: Pharmaceutical Parameters
Solid dosage forms such as tablets and capsules undergo rigorous manufacturing processes to ensure stability and effectiveness. Their dissolution and absorption properties are influenced significantly by the choice of excipients (inactive ingredients that serve various roles in the formulation), and the methodology applied during production. The manufacturing parameters, such as compression force and granulation techniques, significantly affect dissolution rates. Elevated compression forces...
01:23Factors Affecting Dissolution: Particle Size and Effective Surface Area
Dissolution kinetics, an essential aspect of oral drug delivery, is significantly influenced by the drug's particle size. According to the Noyes-Whitney dissolution model, the dissolution rate correlates directly with the drug's surface area. The larger the surface area, the higher the drug's solubility in water, leading to a faster drug dissolution rate. Reducing particle size increases the effective surface area, enhancing the dissolution process. Micronization and nanosizing are employed to...