A study of the permeation and water-structuring behavioural properties of PEG modified hydrated silk fibroin membranes

Abstract

The potential of naturally occurring substances as a source of biomedical materials is well-recognised and is being increasingly exploited. Silk fibroin membranes derived from Bombyx mori silk cocoons exemplify this, for example as substrata for the growth of ocular cells with the aim of generating biomaterial-cell constructs for tissue engineering. This study investigated the transport properties of selected silk fibroin membranes under conditions that allowed equilibrium hydration of the membranes to be maintained. The behaviour of natural fibroin membranes was compared with fibroin membranes that have been chemically modified with poly(ethylene glycol). The permeation of the smaller hydrated sodium ion was higher than that of the hydrated calcium ion for all three ethanol treated membranes investigated. The PEG and HRP-modified C membrane, which had the highest water content at 59.6±1.5% exhibited the highest permeation of the three membranes at 95.7±2.8×10 -8 cm 2 s −1 compared with 17.9±0.9×10 -8 cm 2 s −1 and 8.7±1.7×10 -8 cm 2 s −1 for membranes A and B respectively for the NaCl permeant. Poly(ethylene glycol) was used to increase permeability while exploiting the crosslinking capabilities of horseradish peroxidase to increase the compressive strength of the membrane. Importantly, we have established that the permeation behaviour of water-soluble permeants with hydrated radii in the sub-nanometer range is analogous to that of conventional hydrogel polymers.

Regenerated Silk Nanofibers for Robust and Cyclic Adsorption–Desorption on Anionic Dyes

“…FTIR provides evidence of the change in the chemical structure of neat silk nanofibers after interaction with ethanol. Two significant bands at 1646 cm –1 (amide-I) and 1541 cm –1 (amide-II) of neat silk nanofibers were observed (Figure f), which are in good agreement with previously reported works of neat silk nanofibers. , However, these peaks of amide-I (at 1646 cm –1 ) and amide-II (at 1541 cm –1 ) were shifted to 1625 and 1521 cm –1 , respectively, after treating pristine silk nanofibers with ethanol (75%, v/v) confirms the transmittance of adsorption peaks and hence successful crosslinking of silk nanofibers. , …”

Influence of Fibroin Membrane Composition and Curing Parameters on the Performance of a Biodegradable Enzymatic Biosensor Manufactured from Silicon‐Free Carbon

“…One explanation might be due to the longer diffusion path of the analyte molecules through the swollen membrane. [ 42 ] Ecoflex and the material combination of wound adhesive and PLA prevented a sensory reaction to the addition of H 2 O 2 . Especially, the findings for PLA emphasize the results of swelling tests in Section 3.3.…”

“…[41] In contrast, the biodegradability of fibroin can be influenced by manipulating the β-sheet fraction in the semicrystalline polymer. [42,43] The β-sheet content influences not only the velocity of biodegradation, but also other properties such as water solubility, tensile strength, and flexibility. [44] Several methods are discussed to influence the β-sheet fraction, such as, by exposing the sample to water, ethanol, or methanol vapor.…”

Tough silk fibroin hydrogel via polypropylene glycol (PPG) blending for wearable sensors

“…However, if the PPG content is further increased, the PPG molecules start to form clusters, separating from the silk fibrous structure. This disrupts the uniform system and significantly decreases the mechanical properties 33–36 …”

“…This disrupts the uniform system and significantly decreases the mechanical properties. [33][34][35][36] Although the toughness of the material is greatly enhanced after mixing a certain amount of PPG, it will inevitably cause energy loss during the stretching process. Since the composite hydrogel is expected to be used for human skin sensing, there are corresponding requirements for the fatigue resistance of the material.…”