A redox strategy to tailor the release properties of Fe(III)-alginate aerogels for oral drug delivery

Abstract

Iron(III)-crosslinked alginate aerogel beads (d = 3-5 mm) were prepared and loaded with ibuprofen by using the technique of adsorptive deposition from supercritical CO 2 . Additional formulations were prepared where the aerogels were co-impregnated by ibuprofen and ascorbic acid. The release of ibuprofen from the Fe(III)-alginate is much faster in pH = 7.4 (PBS) than in pH = 2.0 (HCl), which can be explained by the faster dissolution and higher swelling of the alginate matrix in PBS. By decreasing the size of the beads and using a higher G content alginate the release rate could be slightly increased. A marked acceleration of drug release was achieved in both HCl and PBS by incorporating ascorbic acid into the Fe(III)-alginate aerogel preparations. The explanation is that in aqueous media ascorbic acid in situ reduces the crosslinking Fe(III) to Fe(II). The latter does not interact strongly with alginate, which promotes the hydration of the chains, thus the erosion and dissolution of the carrier matrix.

Review on the Production of Polysaccharide Aerogel Particles

“…They can potentially cover the size requirements for a specific administration route allowing for a reasonably high throughput. Oral [190,216,217], mucosal [218], and most recently pulmonary [219] drug delivery routes have been exemplified in the literature. Furthermore, thanks to high pore volume and swelling ability both pristine and drug-loaded polysaccharide aerogel particles have been suggested as superabsorbent and for wound healing applications [56,74].…”

Alginate-Based Aerogel Particles as Drug Delivery Systems: Investigation of the Supercritical Adsorption and In Vitro Evaluations

“…These properties include high specific surface area, high porosity along with low density, high sorption capacity and, most importantly, biocompatibility, which guarantees complete safety for humans [11]. Of particular interest is the use of organic aerogels in the form of particles as drug delivery systems, since the impregnation of various active substances in aerogels allows obtaining compositions with improved pharmacokinetic properties, for example, with improved bioavailability, fast or, conversely, slow release of the active substance from the pores of the aerogel [12][13][14].…”

Alginate-Based Platforms for Cancer-Targeted Drug Delivery

“…The model drug, nicotinic acid, was added to the alginate solution before crosslinking. Veres et al prepared iron(III)-crosslinked alginate aerogel beads loaded with ibuprofen using the technique of adsorptive deposition from supercritical CO 2 (sc-CO 2 ) [ 62 ]. The aqueous alginate solution was dropped into an FeCl 3 gelation bath and aged in FeCl 3 solution for 24 h. After multiple-step solvent exchange process, the alginate gel beads were dried under supercritical CO 2 at 45°C and 140 bars using a continuous flow process in a high-pressure autoclave to form aerogels.…”