Ultrasonic studies on lamivudine: beta-cyclodextrin and polymer inclusion complexes
1Department of Physics, Annamalai University, Annamalainagar-608002, Tamil Nadu, India.
Pakistan Journal of Biological Sciences : PJBS
|September 27, 2008
Summary
Polyvinyl alcohol (PVA) enhances Lamivudine solubility and stability by forming ternary complexes with beta-cyclodextrin (beta-CD). This improves drug performance through specific intermolecular interactions and increased binding constants.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
Background:
- Drug solubility and stability are critical for biological performance.
- Cyclodextrins and polymers are often used to improve drug delivery characteristics.
Purpose of the Study:
- To enhance the solubility and stability of Lamivudine using a combination of beta-cyclodextrin (beta-CD) and polyvinyl alcohol (PVA).
- To investigate the intermolecular interactions between Lamivudine, beta-CD, and PVA using ultrasonic techniques.
Main Methods:
- Preparation of binary (Lamivudine: beta-CD) and ternary (Lamivudine: beta-CD: PVA) inclusion complexes.
- Ultrasonic technique was employed to study intermolecular interactions at various PVA concentrations (303 K).
Main Results:
- Polyvinyl alcohol (PVA) interacts with both free Lamivudine and the Lamivudine: beta-CD complex.
- A ternary complex (Lamivudine: beta-CD: PVA) was successfully formed, altering the drug: beta-CD interaction.
- PVA significantly increased the binding constant, particularly at a 1.25% concentration.
- In the ternary complex, beta-CD encapsulates Lamivudine at both ends, with PVA acting as a bridging molecule between beta-CD units.
Conclusions:
- The ternary complex formation significantly enhances Lamivudine solubility and stability.
- PVA acts as an effective complexing agent, improving the drug delivery potential of Lamivudine-beta-CD systems.
- The study demonstrates a novel approach to drug formulation for improved bioavailability.
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