Colon targeted beads loaded with pterostilbene: Formulation, optimization, characterization and in vivo evaluation

Area of Science:

• Pharmacology
• Drug Delivery Systems
• Nanotechnology

Background:

• Pterostilbene exhibits chemopreventive properties against colon cancer.
• Low bioavailability and poor colonic tissue penetration limit pterostilbene's effectiveness.
• Oral colon-targeted drug delivery is crucial for maximizing pterostilbene's therapeutic potential.

Purpose of the Study:

• To formulate and optimize oral colon-targeted pterostilbene beads.
• To enhance pterostilbene's bioavailability and colonic distribution.
• To overcome the limitations of pterostilbene's low bioavailability.

Main Methods:

• Ionic gelation using pectin and zinc acetate for bead formulation.
• 2^3 factorial design for optimizing pectin concentration, zinc acetate concentration, and pterostilbene:pectin ratio.
• Coating with Eudragit S-100 using a fluidized bed coater.
• Characterization of beads for entrapment efficiency, in vitro release, size, swelling, and surface morphology.
• Pharmacokinetic and organ distribution studies in rats.

Main Results:

• Optimized beads (2% pectin, 2% zinc acetate, 1:4 pterostilbene:pectin ratio) showed 64.80% entrapment efficiency and 37.88% in vitro release at 24 hours.
• Coated beads exhibited a smooth surface and optimal drug release.
• Pharmacokinetic studies revealed delayed Tmax (22h) for coated beads compared to plain pterostilbene (3h).
• Significantly higher pterostilbene distribution in colonic tissue was observed.

Conclusions:

• The developed oral colon-targeted beads effectively improved pterostilbene's bioavailability.
• The formulation successfully targeted pterostilbene delivery to the colon.
• This approach holds promise for enhancing pterostilbene's chemopreventive efficacy in colon cancer.