Electrosprayed Alginate-Fmoc Amino Acid Microcapsules for Quercetin Loading and Release

Area of Science:

• Materials Science
• Biomedical Engineering
• Drug Delivery

Background:

• Alginate microcapsules are widely used for drug delivery.
• Enhancing the structural integrity and release profile of alginate microcapsules is crucial for effective drug delivery.
• Quercetin is a bioactive compound with therapeutic potential, requiring suitable delivery systems.

Purpose of the Study:

• To develop and characterize novel hybrid microcapsules by incorporating Fmoc-Tyrosine (Fmoc-Y) or Fmoc-Proline (Fmoc-Pro) into alginate.
• To evaluate the impact of these hybrid structures on quercetin loading, release kinetics, and swelling properties.
• To assess the structural stability and morphological changes of the microcapsules under different pH conditions.

Main Methods:

• Hybrid microcapsules were synthesized by incorporating Fmoc-Y or Fmoc-Pro into alginate, followed by Ca2+-ion cross-linking.
• Characterization included particle size analysis, Fourier-transform infrared spectroscopy (FTIR), rheological studies, and scanning electron microscopy (SEM).
• Quercetin release profiles and microcapsule swelling behavior were investigated at pH 7.4 and pH 1.2, respectively.

Main Results:

• Hybrid microcapsules (Ca-Alginate/Fmoc-Y and Ca-Alginate/Fmoc-Pro) exhibited smaller particle sizes (154 ± 14 μm and 131 ± 15 μm) compared to pure Ca-Alginate (187 ± 19 μm).
• FTIR confirmed the successful incorporation of Fmoc-amino acids into the alginate matrix.
• Quercetin release at pH 7.4 was significantly prolonged in hybrid microcapsules (up to 24 h) compared to pure alginate (7 h), following Korsmeyer-Peppas and zero-order models, respectively.
• Hybrid microcapsules demonstrated superior structural stability and reduced erosion at pH 7.4 (stable up to 16 h) compared to pure alginate microcapsules (eroded by 6 h).
• SEM analysis revealed a more compact and less porous surface morphology for hybrid microcapsules.

Conclusions:

• The incorporation of Fmoc-Y and Fmoc-Pro into alginate significantly enhances the structural durability and controlled release of quercetin from microcapsules.
• Hybrid microcapsules offer improved performance for drug delivery applications, maintaining integrity over extended periods and controlled release profiles.
• These findings highlight the potential of Fmoc-amino acid-modified alginate as a promising platform for advanced drug delivery systems.