A Carbodiimide Cross‐Linked Silk Fibroin/Sodium Alginate Composite Hydrogel with Tunable Properties for Sustained Drug Delivery

Abstract

Carbodiimide cross-linked silk fibroin (SF)/sodium alginate (SA) composite hydrogels with superior stability and tunable properties are developed by varying preparation parameters. SF/SA blend ratio modulation allows to achieve composite hydrogel gelation times of 18-65 min, and rheological analysis shows that the speed of gel formation, the hydrogel network's density, and the hydrogels' compressive properties are closely related to the blend ratio. The G′ of different hydrogels varies substantially from 28 to 413 Pa, and the hydrogel with higher SF content has a greater stiffness. The composite hydrogels present appropriate porosity of 76.63-85.09% and pore size of 316-603 μm. Hydrogel stability improves significantly after cross-linking, and substantial swelling occurs due to the hydrophilicity of SA. The 7/3 and 6/4 SF/SA hydrogels are more resistant to degradation in PBS, and cytotoxicity testing confirmed their biocompatibility. For release studies in vitro, two model compounds are used as drug models, tetracycline hydrochloride, and bovine serum albumin (BSA). Different ratios of SF/SA have a greater influence on the release of BSA. This study provides a practical preparation method for flexible SF/SA composite hydrogels, which can help design hydrogels with specific physicochemical properties for different applications, especially drug delivery.

A Biomimetic Composite Bilayer Dressing Composed of Alginate and Fibroin for Enhancing Full‐Thickness Wound Healing

“…[ 21–23 ] This SF/SA composite scaffold or gel was similar to the native ECMs, which demonstrated a steady porous structure, improved swelling capacity, and provided good cytocompatibility. [ 24,25 ] Moreover, this composite scaffold is biodegradable, making it readily replaceable by regenerated tissue. [ 26 ]…”

“…[21][22][23] This SF/SA composite scaffold or gel was similar to the native ECMs, which demonstrated a steady porous structure, improved swelling capacity, and pro-vided good cytocompatibility. [24,25] Moreover, this composite scaffold is biodegradable, making it readily replaceable by regenerated tissue. [26] Many recent reports documenting the use of SF/SA composite materials for wound healing have assessed SF/chitosan/SA multilayer membranes, a SA hydrogel with an electrospun SF mat, and an SF/hyaluronic acid/SA scaffold, among others.…”

Preparation and Characterization of Natural Silk Fibroin Hydrogel for Protein Drug Delivery

“…The FITC-labeled BSA was used as a protein drug model, which was dissolved in PBS buffer and mixed by vortexing to obtain a drug solution with a specific concentration [ 45 ]. According to Formula (4), the drug loading content ( DLC ) was set to 10, 20, 30, 40, 50, 60, 70, 80, and 90%, and the concentration of the protein drug solution was calculated.…”

Electrodeposited Alginate‐Based Green Synthesis of CuS Nanoparticles and Nanocomposite Films for Electrochemical and Colorimetric Detection

“…[ 23 ] Alginate has been extensively applied in wound healing, drug delivery, and sensors owing to its non‐toxicity, low cost, biocompatibility, and biodegradability. [ 24–29 ] It should be noted that alginate contains functional groups such as ‐OH and ‐COOH groups, which can form hydrogels with metal ions due to the chelation of alginate with metal ions. [ 30 ] Wang et al.…”

“…[23] Alginate has been extensively applied in wound healing, drug delivery, and sensors owing to its nontoxicity, low cost, biocompatibility, and biodegradability. [24][25][26][27][28][29] It should be noted that alginate contains functional groups such as -OH and -COOH groups, which can form hydrogels with metal ions due to the chelation of alginate with metal ions. [30] Wang et al used alginate solution for direct gelation with metal ions (Pb 2+ , Cu 2+ , and Cd 2+ ) toward the removal and recovery of heavy metals, and they pointed out that the gelation mainly occurred between the metal ions and the -COOH and -OH groups on alginate.…”