Comparison of silk fibroin electrospun scaffolds with poloxamer and honey additives for burn wound applications

A primary aim in wound-healing research is to construct an inexpensive, biodegradable dermal regeneration template with heightened moisture retention and permeability properties. The presence of moisture is important for optimal burn wound healing as it creates an environment for re-epithelialization and minimizes the risk of infections. Permeability can be achieved through a process known as electrospinning. This scaffold fabrication technique creates a mat of randomly oriented nanofibers that can readily mimic native extracellular matrix. Novel electrospun silk fibroin scaffolds were fabricated with poloxamer 407 (P407) and Manuka honey additives for a burn wound dermal regeneration template application. Enhanced human dermal fibroblast adhesion and cell infiltration were observed with the inclusion of P407, and scaffolds incorporated with Manuka honey demonstrated increased water uptake and a higher cell density within the scaffolds at the end of a 28-day period. Overall, this study established that both the silk fibroin/P407 and silk fibroin/Manuka honey scaffolds have the potential to be successful dermal regeneration templates, with P407 increasing surface wettability and Manuka honey modulating moisture retention.

Mechanisms and control of silk-based electrospinning

Silk fibroin (SF) nanofibers, formed through electrospinning, have attractive utility in regenerative medicine due to the biocompatibility, mechanical properties, and tailorable degradability. The mechanism of SF electrospun nanofiber formation was studied to gain new insight into the formation and control of nanofibers. SF electrospinning solutions with different nanostructures (nanospheres or nanofilaments) were prepared by controlling the drying process during the preparation of regenerated SF films. Compared to SF nanospheres in solution, SF nanofilaments had better spinnability with lower viscosity when the concentration of silk protein was below 10%, indicating a critical role for SF morphology, and in particular, nanostructures, for the formation of electrospun fibers. More interesting, the diameter of electrospun fibers gradually increased from 50 to 300 nm as the concentration of SF nanofilaments in the solution increased from 6 to 12%, implying size control by simply adjusting SF nanostructure and concentration. Aside from process parameters investigated in previous studies, such as SF concentration, viscosity, and electrical potential, the present mechanism emphasizes significant influence of SF nanostructure on spinnability and diameter control of SF electrospun fibers, providing a controllable option for the preparation of silk-based electrospun scaffolds for biomaterials, drug delivery, and tissue engineering needs.