Fabrication and characterization of silk sericin based composite films for biomedical applications

Haliloğlu, Alper
Silk Sericin (SS) is one of the two major proteins in silk fiber and it is discarded as a waste in the silk industry. Recently, sericin captured attention in the biomedical field due to its variable amino acid composition and diverse functional groups. The physical and chemical properties of silk sericin can be adjusted via incorporation of different secondary phase additives for biomedical applications. However, brittle nature, low mechanical properties, and inability to avoid bacterial growth by itself limits its use in such areas. In this study, high temperature and pressure method is used to extract sericin from silk cocoons. To fabricate sericin based composite films, extracted sericin is combined with different agents, namely glycerol to overcome the brittle characteristics, as well as Sr and Zn incorporated bioactive glass (BG) particles and graphene oxide (GO) to provide mechanical durability and antibacterial properties. SEM images of the sericin based composite films showed that reinforcements were homogenously distributed throughout the films without any agglomeration. Thermogravimetric analysis showed that nearly 35% of the initial mass of the sericin films were lost during the early stages of degradation, which was correlated with glycerol diffusing out the system. Moreover, approximately 85-105 % swelling was observed upon soaking sericin films in 1xPBS, which indicated their good water retention ability. The Young’s modulus values of silk sericin based films increased from 16.7±0.9 MPa up to 19.3±1.9 MPa and 22.4±0.6 MPa upon 1% GO and 7% BG addition, respectively. When L929 fibroblast cells were treated with extracts of silk sericin films, no toxicity was observed and cellular viability was promoted up to 7 days of culture in vitro. Both reinforcement materials (GO and BG) exhibited antibacterial activity against gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli) strains in a concentration dependent manner. Cumulatively, the obtained results showed that silk sericin based composite films are promising candidates for biomaterial applications.


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Sericin is a silk protein discarded with silk degumming wastewater. Life cycle assessment of sericin recovery from silk degumming wastewater was conducted considering two scenarios; base scenario (no recovery), and sericin recovery with membrane hybrid processes. Base scenario consists of silk degumming and treatment of degumming wastewater. The recovery scenario consists of sericin recovery with the process train; silk degumming, sedimentation, nanofiltration (NF), precipitation and lyophilization. Spray d...
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Sericin, a silk protein, has high potential for use in biomedical applications. In this study, wound dressing membranes of Sericin (S) and Collagen (C) were prepared by glutaraldehyde cross-linking at S/C; 2:1,1:1, 1:2, and 0:1 weight ratios. They were stable in water for 4 weeks. However, increasing the proportion of sericin had decreasing effect on the membrane stability. Water swelling property of membranes was enhanced with sericin. The highest water swelling was obtained in 1:1 group (9.06 g/g), but in...
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Citation Formats
A. Haliloğlu, “Fabrication and characterization of silk sericin based composite films for biomedical applications,” M.S. - Master of Science, Middle East Technical University, 2023.