Abstract
A novel dressing material – silk fibroin fabric (SF)-l-Cysteine (l-Cys) – is here developed to be used as standard treatment for atopic dermatitis (AD), which combines comfort, thermic, and tensile strength properties of silk materials with antioxidant and antimicrobial effects of l-Cys. A careful understanding about the linking strategies is needed in order not to compromise the bioavailability of l-Cys and deplenish its bioactivity. Durability was also addressed through washing cycles and compared with hospital requirements, according to international Standard EN ISO 105-C06:2010. The present research also analyze the interactions between Staphylococcus aureus and SF-l-Cys under simulating conditions of AD and demonstrated the effectiveness of a double covalent grafting, with the importance of SF tyrosine (Tyr) covalent linkage with l-Cys (SF-g-l-Cys/Tyr-g-l-Cys) even after several washing cycles, twenty five, whereas for a disposable application a single covalent mechanism of grafting l-Cys proved to be sufficient (SF-g-l-Cys). Results showed effective antimicrobial activities exhibiting higher inhibition ratios of 98.65% for SF-g-l-Cys after 5 washing cycles, whereas 97.55% for SF-g-l-Cys/Tyr-g-l-Cys after 25 washing cycles, both at pH 9.5 grafting strategy. Furthermore, it is also reported a non-protumoral effect of l-Cys. A new advance is herein achieved at the world of medical antimicrobial textiles tailored to address wound moisture environment and exudate self-cleaning, which may open novel applications as complementary therapy for AD disease.
Highlights
Silk, produced by silkworm Bombyx morii, consists of fibroin and sericin
Minimal inhibitory concentration (MIC) evaluation Minimal inhibitory concentration (MIC) determination was performed with the microdilution method in accordance with M07-A6 guidelines applied to S. aureus (ATCC 6538) – Standard JIS L 1902:2002
The reduction capability of the DPPH◦ radical was determined by the decrease on its absorbance at 517 nm, induced by Cysteine
Summary
Silk, produced by silkworm Bombyx morii, consists of fibroin and sericin. Fibroin, which is the structural protein of silk fibers, comes out from the silkworm gland in the form of filaments enclosed in a water-soluble sericin gluelike coating [1]. Silk fibroin (SF) is composed of heavy (350 kDa) and light chain (25 kDa) polypeptides linked by a disulfide bond [2,3]. SF presents tyrosine (4.8%), which has an aromatic side chain [4]. They form flexible and stretching resistant secondary structure beta-sheets, which render silk its characteristic mechanical strength [5,6,7]. Sugihara et al [10] postulated that wounds treated with a silk dressing healed 7 days faster, by promoting the enhanced synthesis of collagen and epithelialization [10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
