Formation of silk fibroin hydrogel and evaluation of its drug release profile

Abstract

Silk hydrogels are interesting materials to be used as matrix in controlled drug delivery devices. However, methods to accelerate fibroin gelation and allow the drug incorporation during the hydrogel preparation are needed in literature. In this article we report the preparation of silk fibroin hydrogels with addition of several contents of ethanol, used to accelerate fibroin gelation kinetics, and we also evaluate the potential of these hydrogels to be used as matrices for drug delivery. Chemical and conformational properties did not change despite the amount of ethanol incorporated in the hydrogel. Hydrogels containing diclofenac sodium dissolved in ethanol showed a faster initial release of the drug than hydrogels with the drug dissolved in water but equilibrium was reached later. This indicates a more sustained drug delivery from hydrogels in which the model drug was dissolved in ethanol. Fibroin hydrogels confirm their promising use as biopolymeric matrices for controlled drug release. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41802.

Usnic‐Acid‐Functionalized Silk Fibroin Composite Scaffolds for Cutaneous Wounds Healing

“…As shown in Figure 2 a, in the FTIR spectra, an absorption peak at 1644 cm −1 was observed in untreated scaffolds attributed to the noncrystalline structure, such as α‐helix (1600–1615 cm −1 , 1711–1720 cm −1 ), random coil (1641–1646 cm −1 ) and β‐turn (1661–1685 cm −1 ), which were consistent with previous studies. [ 15,33 ] In contrast, the intensity of β‐sheet at 1631 cm −1 was significantly increased after methanol treatment, indicating an increase of the β‐sheet content (Figure 2a,b). Furthermore, Fourier self‐deconvolution to the original spectra was performed followed by curve fitting (Figure 2c,d).…”

Preparation, Characterization and Antifungal Activity Studies of AgNPs Loaded Silk Fibroin Hydrogels

“…Hydrogels based drug delivery systems are engineered materials that use hydrogels as encapsulation of drugs and cells, vehicles for the targeted delivery and controlled release of therapeutic agents [1]. Several applications in pharmaceutical and medical technology are based on dispersions of particles in a fluid or gel phase [2].…”

“…In the last three decades, micro and nanoparticles based polymeric systems have been widely explored for controlled and targeted delivery of drugs and antigens in variety of forms (films, gels, capsules, tablets and creams) mainly due to their ability to sustained drug release for long periods of time, enhanced target, low toxicity, easy manipulation/administration [3][4][5][6]. The release properties, the load-bearing capacity, the porosity, and the cell-matrix interactions should be considered for the development of a material to be used in controlled drug delivery and also as scaffolds for tissue engineering [7][8][9] Also, the possibility to adjust the release profile of a polymeric system is important to achieve the therapeutic concentration of the drug [1]. Silk fibroin (SF) is a protein fiber whose level of crystallinity and molecular conformation makes it a good candidate for controlled drug delivery device.…”

In situ film forming fibroin gel intended for cutaneous administration

“…Silk fibroin is a naturally occurring protein extracted from the silkworm Bombyx mori cocoons and shaped 20 into films (Hofmann et al, 2006), gels (De Moraes et al, 2015;Pritchard et al, 2013), microspheres (Cilurzo et al, 2011), under mild and all-aqueous conditions . In particular, silk fibroin films in On the bases of these considerations, the present work explored the possible use of silk fibroin gel as in situ film forming formulation for cutaneous administration of drugs using ethanol, a volatile and skin 40 tolerant solvent, to favor the sol-gel transition of silk fibroin solutions (De Moraes et al, 2015).…”

“…Solvent exposition is known also to induce silk fibroin gelation (De Moraes et al, 2015). Gels are stabilized by the formation of thermodynamically stable β-sheets, which serve as physical cross-links to stabilize gels and are essentially 240 irreversible under physiological conditions, unless degraded due to enzymatic or oxidative processes.…”