Related Experiment Video
Updated: Apr 20, 2026
08:18
Self-Nanoemulsification of Healthy Oils to Enhance the Solubility of Lipophilic Drugs
Published on: July 27, 2022
1.7K
Development and physicochemical characterization of sirolimus solid dispersions prepared by solvent evaporation
Shahram Emami1, Hadi Valizadeh2, Ziba Islambulchilar3
1Students' Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
Advanced Pharmaceutical Bulletin
|December 2, 2014
Summary
Solid dispersions of sirolimus were prepared using polyvinylpyrrolidone (PVP) and other excipients to enhance drug dissolution. The prepared solid dispersions significantly improved sirolimus release compared to physical mixtures.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
Background:
- Sirolimus exhibits poor aqueous solubility, limiting its therapeutic efficacy.
- Enhancing sirolimus dissolution is crucial for improving its bioavailability.
Purpose of the Study:
- To prepare and characterize sirolimus solid dispersions using the solvent evaporation technique.
- To evaluate the impact of solid dispersions on sirolimus dissolution properties.
Main Methods:
- Solid dispersions prepared using polyvinylpyrrolidone (PVP), Poloxamer 188, and Cremophore RH40 via solvent evaporation.
- In vitro dissolution studies conducted using USP type I apparatus in distilled water with SLS.
- Characterization via Fourier Transform Infrared (FTIR) Spectroscopy and Differential Scanning Calorimetry (DSC).
Main Results:
- All prepared solid dispersions showed over 75% sirolimus release within 30 minutes.
- Dissolution rates of solid dispersions surpassed those of physical mixtures.
- DSC indicated conversion of crystalline sirolimus to amorphous form; FTIR showed no significant drug-carrier interactions.
Conclusions:
- Solid dispersion technique effectively improves the dissolution rate of sirolimus.
- PVP, Poloxamer 188, and Cremophore RH40 are suitable carriers for sirolimus solid dispersions.
- Amorphous conversion contributes to enhanced drug release.
Related Concept Videos
01:28Factors Influencing Drug Absorption: Pharmaceutical Parameters
799
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...
799
01:14Drug Dissolution: Requirements and Profile Comparison
463
The acceptance criteria for dissolution profile data are anchored in Q values, representing the percentage of drug dissolved within a specified period. This assessment unfolds in three stages:First Stage: The test passes if all six drug dosage units are equal to or greater than Q plus 5%; otherwise, the sample proceeds to the second stage.Second Stage: The average of twelve units must be equal to or greater than Q, with no unit falling below Q - 15% to pass; if not, it progresses to the final...
463
01:27Pharmaceutical Alternatives: Polymorphic Form-Related and Particle Size-Related Therapeutic Nonequivalence
227
Changes in polymorphic forms can significantly influence the bioavailability of poorly soluble drugs. Although the FDA defines pharmaceutical equivalence based on having the same active ingredient, dosage form, and route of administration, it does not automatically disqualify products with different polymorphic forms. This means two products with different polymorphs can still be deemed pharmaceutically equivalent. However, polymorphic differences can affect properties like wettability,...
227
01:23Factors Affecting Dissolution: Particle Size and Effective Surface Area
2.1K
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...
2.1K
01:16Bioavailability Enhancement: Drug Solubility Enhancement
470
Bioavailability is a critical factor in determining a drug's effectiveness. It refers to the proportion of a drug that enters the circulation when introduced into the body and is, as a result, able to have an active effect. Enhancing bioavailability is essential for drugs with poor solubility, as it can significantly impact their therapeutic efficacy. Various methods are employed to increase the solubility of drugs, thereby enhancing their bioavailability.Micronization and nanonization are...
470
01:21Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
897
Polymorphism refers to the existence of a drug substance in multiple crystalline forms, known as polymorphs. Recently, this term has been expanded to include solvates (forms containing a solvent), amorphous forms (non-crystalline forms), and desolvated solvates (forms from which the solvent has been removed).
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
897