Synthesis and characterization of biodegradable hydrogels for oral delivery of 5-fluorouracil targeted to colon:screening with preliminary in vivo studies

In this communication, we developed a thermally stable, biocompatible, and colonically degradable hydrogel-based device [pectin-co-poly(MAA)] for oral delivery of 5-fluorouracil (5-FU) to treat colon cancer with minimal upper gastrointestinal invasion. Toward this end, ethylene glycol dimethacrylate (EGDMA) cross-linked hydrogels of pectin were synthesized. Methacrylic acid (MAA) was grafted to impart pH-responsive character, whereas benzoyl peroxide (BPO) was applied for simultaneous grafting and cross-linking polymerization. The hydrogels were characterized by Fourier transform infrared , thermogravimetric analysis, differential scanning calorimetry, and X-ray diffractometry. Scanning electron microscopic photographs were taken to analyze the surface morphology. Swelling behavior was analyzed to assess better performance of biodegradable hydrogels for optimized loading and release of the drug targeted to the colon. Gel fraction, swelling ratio, diffusion coefficient, drug loading, and cumulative release increased with an increase of pectin ratio and decreased with an increase of MAA and EGDMA ratio. Strategically, hydrogels with higher amounts of pectin were prepared for complete degradation in the colon. Our investigations indicate that pectin-co-poly(MAA) hydrogel is a suitable delivery system developed for oral delivery of the drug targeted to the colon.