Dissolution behaviour of nalidixic acid solid dispersions using water soluble dispersion carriers

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Materials Science

Background:

• Nalidixic acid (NA) exhibits low oral bioavailability due to poor solubility and slow dissolution.
• Effective drug delivery strategies are crucial for enhancing the therapeutic efficacy of poorly soluble drugs like NA.

Purpose of the Study:

• To improve the dissolution rate and oral bioavailability of nalidixic acid (NA).
• To investigate the potential of solid dispersions using various carriers for NA formulation.

Main Methods:

• Solid dispersions of NA were prepared with polyvinylpyrrolidone (PVP), beta-cyclodextrin (BCD), and sodium starch glycolate (SSG) via solvent evaporation.
• Physical characterization employed scanning electron microscopy (SEM), infrared (IR) spectroscopy, and powder X-ray diffraction (XRD).
• Dissolution studies were conducted to evaluate drug release profiles and efficiency.

Main Results:

• SEM confirmed drug inclusion within dispersion systems.
• IR analysis indicated no significant drug-carrier interactions.
• XRD showed a reduced degree of crystallinity for NA in solid dispersions.
• Dissolution rate and dissolution efficiency (DE) were significantly enhanced in solid dispersions compared to pure NA.
• Carrier potency order for enhancing dissolution: BCD > PVP > SSG.
• Smaller drug-to-carrier ratios resulted in faster dissolution rates.

Conclusions:

• Solid dispersions effectively enhance the dissolution rate of nalidixic acid.
• Beta-cyclodextrin (BCD) is the most potent carrier among those tested.
• Formulation parameters like drug-to-carrier ratio significantly influence drug release kinetics.
• First-order kinetics model can describe drug release from these solid dispersion systems.