Controlled release of 5-flurouracil from biomedical polyurethanes

Abstract

Novel biodegradable aliphatic poly(ether-urethane)s (PEUs) based on pluronic F-68 (PLF68) and castor oil were synthesized by the solution polymerization technique. These polymers were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic spectroscopy ( 1 HNMR) and gel permeation chromatography (GPC) to confirm the PEU formation and the molecular weight. Moderate molecular weight PEUs were obtained and converted into microspheres by solvent evaporation method to study the controlled release (CR) characteristics for 5-flurouracil (5-FU). PLF-68 acts as amphiphilic filler, which enhances the release of a hydrophobic drug such as 5-FU. Sizes of the microspheres as measured by laser light scattering technique ranged between 15 and 42 µm. An increase in the size of particles was observed with increasing molar ratio of PLF-68 with respect to castor oil. The percentage encapsulation efficiency varied between 71 and 98. Surface morphology of the microspheres as studied by scanning electron microscopy (SEM) revealed the spherical nature of the particles with wrinkles on their surfaces. The release of 5-FU through the microspheres was investigated in pH 7⋅4phosphate buffer. An increase in release rate was observed with increasing molar ratio of PLF68 with respect to castor oil.

Synthesis of a novel pH‐sensitive polyurethane–alginate blend with poly(ethylene terephthalate) waste for the oral delivery of protein

“…It was clear from this study that the beads with more alginate survived in the PBS (pH 7.4) medium for the maximum time. Various polymeric systems, such as chitosan, gelatin, and hydroxyapatite, have been studied to investigate the release patterns of protein or drug from them . It was reported that a burst release of BSA was found in the case of a chitosan–alginate blend as a delivery system .…”

“…To fulfill that criterion, sodium alginate (SA) was blended with the synthesized PU, and partially crosslinked beads were prepared with a calcium chloride solution. The stability of the encapsulated protein during the processing, release, storage, safety, and biocompatibility of the degradable polymer is also very much necessary for controlled release applications . In the systemic delivery of proteins, biodegradable polymeric microspheres occupy an important place because of several aspects, such as the protection of sensitive proteins from degradation, the maintenance of the protein structure, sustained release patterns, and improved bioavailability.…”

Polyurethane for biomedical applications: A review of recent developments

“…The release behaviors of many other small molecular drugs were also studied, such as ibuprofen, 5-fl urouracil, etc. (Ring et al, 2008;Basa et al, 2009;Harisha et al, 2010). Beyond these small molecular drugs, Li et al (2009) incorporated rhBMP-2 (recombinant human bone morphogenetic protein) into polyurethane scaffolds implanted in rat femoral plug defects, and the research results clearly showed that at 4 weeks post-implantation, all rhBMP-2 treatment groups showed enhanced new bone formation relative to the scaffolds without rhBMP-2, an impressive improvement ( Figure 3.2 ).…”

Preparation and characterization of novel antibacterial castor oil-based polyurethane membranes for wound dressing application

“…Therefore, CO can be used directly as a starting material for the preparation of polyurethanes, polyesters, polyamides, epoxy resins, and alkyd resins . Owing to their significant biocompatibility, vegetable oil‐based polyurethanes found interesting applications in biomedical area such as drug delivery systems, bone tissue engineering, bioadhesives, and wound dressing …”