Effects of silk degumming process on physicochemical, tensile, and optical properties of regenerated silk fibroin

Kira Nultsch, Livia K. Bast, Muriel Näf, Salima El Yakhlifi, Nico Bruns, Oliver Germershaus

Research output: Contribution to journalArticle

3 Citations (Scopus)
3 Downloads (Pure)

Abstract

Sericin removal from silk (degumming) affects material characteristics of silk fibroin (SF). Sodium carbonate is most commonly used for degumming, but numerous alternative methods are available. Herein, a systematic comparison of degumming methods is provided. Sodium carbonate, sodium oleate, trypsin, and ionic liquid are used, and materials are characterized regarding mass loss, SF content, molecular integrity of SF, refractive index, and tensile properties. Complete degumming is achieved within 30 min of using sodium carbonate, but results in significant reduction of molecular weight, shift toward less acidic charge variants, and reduction of yield- and rupture force. Sodium oleate and trypsin are inefficient and negatively affect tensile properties, while ionic liquid shows good efficiency and marginal degradation of SF but also reduced yield- and rupture force. Refractive index is not affected by degumming. These results allow rational selection of the degumming method and tuning of SF properties for biomedical applications.

Original languageEnglish
Article number1800408
Number of pages10
JournalMacromolecular Materials and Engineering
Volume303
Issue number12
Early online date21 Sep 2018
DOIs
Publication statusPublished - 31 Dec 2018

Fingerprint

Degumming
Fibroins
Silk
Tensile properties
Optical properties
Sodium
Ionic Liquids
Carbonates
Ionic liquids
Trypsin
Refractive index
Sericins
Tuning
Molecular weight
Degradation

Keywords

  • degumming
  • refractive index
  • silk fibroin
  • silk sericin
  • tensile testing

Cite this

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title = "Effects of silk degumming process on physicochemical, tensile, and optical properties of regenerated silk fibroin",
abstract = "Sericin removal from silk (degumming) affects material characteristics of silk fibroin (SF). Sodium carbonate is most commonly used for degumming, but numerous alternative methods are available. Herein, a systematic comparison of degumming methods is provided. Sodium carbonate, sodium oleate, trypsin, and ionic liquid are used, and materials are characterized regarding mass loss, SF content, molecular integrity of SF, refractive index, and tensile properties. Complete degumming is achieved within 30 min of using sodium carbonate, but results in significant reduction of molecular weight, shift toward less acidic charge variants, and reduction of yield- and rupture force. Sodium oleate and trypsin are inefficient and negatively affect tensile properties, while ionic liquid shows good efficiency and marginal degradation of SF but also reduced yield- and rupture force. Refractive index is not affected by degumming. These results allow rational selection of the degumming method and tuning of SF properties for biomedical applications.",
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Effects of silk degumming process on physicochemical, tensile, and optical properties of regenerated silk fibroin. / Nultsch, Kira; Bast, Livia K.; Näf, Muriel; Yakhlifi, Salima El; Bruns, Nico; Germershaus, Oliver.

In: Macromolecular Materials and Engineering, Vol. 303, No. 12, 1800408, 31.12.2018.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Effects of silk degumming process on physicochemical, tensile, and optical properties of regenerated silk fibroin

AU - Nultsch, Kira

AU - Bast, Livia K.

AU - Näf, Muriel

AU - Yakhlifi, Salima El

AU - Bruns, Nico

AU - Germershaus, Oliver

PY - 2018/12/31

Y1 - 2018/12/31

N2 - Sericin removal from silk (degumming) affects material characteristics of silk fibroin (SF). Sodium carbonate is most commonly used for degumming, but numerous alternative methods are available. Herein, a systematic comparison of degumming methods is provided. Sodium carbonate, sodium oleate, trypsin, and ionic liquid are used, and materials are characterized regarding mass loss, SF content, molecular integrity of SF, refractive index, and tensile properties. Complete degumming is achieved within 30 min of using sodium carbonate, but results in significant reduction of molecular weight, shift toward less acidic charge variants, and reduction of yield- and rupture force. Sodium oleate and trypsin are inefficient and negatively affect tensile properties, while ionic liquid shows good efficiency and marginal degradation of SF but also reduced yield- and rupture force. Refractive index is not affected by degumming. These results allow rational selection of the degumming method and tuning of SF properties for biomedical applications.

AB - Sericin removal from silk (degumming) affects material characteristics of silk fibroin (SF). Sodium carbonate is most commonly used for degumming, but numerous alternative methods are available. Herein, a systematic comparison of degumming methods is provided. Sodium carbonate, sodium oleate, trypsin, and ionic liquid are used, and materials are characterized regarding mass loss, SF content, molecular integrity of SF, refractive index, and tensile properties. Complete degumming is achieved within 30 min of using sodium carbonate, but results in significant reduction of molecular weight, shift toward less acidic charge variants, and reduction of yield- and rupture force. Sodium oleate and trypsin are inefficient and negatively affect tensile properties, while ionic liquid shows good efficiency and marginal degradation of SF but also reduced yield- and rupture force. Refractive index is not affected by degumming. These results allow rational selection of the degumming method and tuning of SF properties for biomedical applications.

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KW - refractive index

KW - silk fibroin

KW - silk sericin

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