Silk is an excellent natural protein fiber as well as a high-quality polymer protein material with good mechanical properties, biocompatibility, controllable biodegradability, etc. With the gradual development of biomaterial field and the cross-integration of various disciplines, silk as a biomaterial has shown the strong competitiveness and exhibited great application potential in this field. In this paper, the composition and characteristics of silk are introduced, and the extracting methods for both silk fibroin and sericin are also summarized. Furthermore, the applications of silk and silk proteins in tissue engineering, drug loading and wound dressing in recent years are reviewed. Besides, the functions of silk and silk proteins for specific applications as well as the advantages and disadvantages of silk-based material are analyzed. Finally, the application prospect of silk in biomaterial field is proposed.
马艳,李智,冉瑞龙,李康. 蚕丝在生物医用材料领域的应用研究[J]. 《材料导报》期刊社, 2018, 32(1): 86-92.
Yan MA,Zhi LI,Ruilong RAN,Kang LI. Research on Application of Silk in Biomaterial Field. Materials Reports, 2018, 32(1): 86-92.
Little damage to silk fibron (SF), no fuzziness, good bulkiness
[21-22]
Soaping method
Moderate SF color, but inferior softness and feel compared to enzymatic method
[21]
Sodium carbonate degumming method
Simple and fast process, but a bit yellow SF color
[23]
Urea degumming method
Favorable and whiter SF color
[23]
Water degumming method
Good degumming effect both in acidic and alkaline aqueous solutions, pleasurable SF color
[24]
表1 蚕丝脱胶方法及特点
Extraction methods for sericin
Characteristics
References
Freezing method
Facile recycling process, yield up to 75% after at low temperature freezing
[26]
Dialysis method
High yield (up to 81.5%)
[26]
Spray-drying method
Short process, suitable for mass production, but low yield(~30%)
[27]
Freeze-drying method
Time-consuming, low efficiency, not suitable for mass production
[27]
表2 丝胶的提取方法及特点
Application
Preparation methods
Characteristics
References
Bone tissue engineering
Coprecipitation method, low-temperature 3D printing, mechanical blending, etc.
Good mechanical properties, promoting a variety of cell adhesion growth, repairing cartilage tissue, delaying the occurrence of arthritis
[28,34]
Tendon and ligament tissue engineering
Weaving, freeze-drying, electrospinning, etc.
Similar mechanical properties to tendons and ligaments, meeting different clinical requirements
[41,71-72]
Vascular tissue engineering
Weaving, electrospinning, etc.
Anticoagulant function, good biocompatibility, favorable to endothelialization in artificial blood vessels
[45,47,72]
Skin tissue engineering
Freeze-drying, electrospinning, etc.
Amino acid composition of silk fibroin is similar to that of human skin, sericin can well promote the growth of fibroblasts
[49,51]
Nerve tissue engineering
3D printing, electrospinning, hypotonic-lyophilization, etc.
Good biocompatibility and compression resistance, no obvious cytotoxicity
[56,73-74]
Drug delivery system
Supercritical fluid technique, freeze- drying, electrospinning, etc.
Good biocompatibility, negligible influence on the biological activity, enabling targeted therapy, controllable drug release
[75-76]
Wound dressing
Dry film-forming, freeze- drying, electrospinning, etc.
Good plasticity, good air permeability, non-toxicity, beneficial to wound healing
[8-9,65]
Hemostatic material
Weaving, freeze-drying, electrospinning, etc.
Good biocompatibility, non-toxicity, less inflammatory response, good air permeability
[68-70]
表3 蚕丝在生物医用材料领域的应用
[1]
Vepari C, Kaplan D L . Silk as a biomaterial[J]. Progress in Polymer Science, 2007,32(8-9):991.
[2]
Jin H J, Kaplan D L . Mechanism of silk processing in insects and spiders[J]. Nature, 2003,424(6952):1057.
[3]
Omenetto F G, Kaplan D L . New opportunities for an ancient material[J]. Science, 2010,329(5991):528.
[4]
Perrone G S, Leisk G G, Lo T J , et al. The use of silk-based devices for fracture fixation[J]. Nature Communications, 2014,5(3):3385.
[5]
Das S, Sharma M, Saharia D , et al. In vivo studies of silk based gold nano-composite conduits for functional peripheral nerve regeneration[J]. Biomaterials, 2015,62:66.
[6]
Guziewicz N A, Massetti A J , Perez-Ramirez B J, et al. Mechanisms of monoclonal antibody stabilization and release from silk biomaterials[J]. Biomaterials, 2013,34(31):7766.
[7]
Lerdchai K, Kitsongsermthon J, Ratanavaraporn J , et al. Thai silk fibroin/gelatin sponges for the dual controlled release of curcumin and docosahexaenoic acid for anticancer treatment[J]. Journal of Pharmaceutical Sciences, 2016,105(1):221.
[8]
Silva R, Fabry B, Boccaccini A R . Fibrous protein-based hydrogels for cell encapsulation[J]. Biomaterials, 2014,35(25):6727.
[9]
Cai Z X, Mo X M, Zhang K H , et al. Fabrication of chitosan/silk fibroin composite nanofibers for wound-dressing applications[J]. International Journal of Molecular Sciences, 2010,11(9):3529.
[10]
MinouraN, Aiba S, Higuchi M , et al. Attachment and growth of fibroblast cells on silk fibroin[J]. Biochemical and Biophysical Research Communications, 1995,208(2):511.
[11]
LinS, Chen M, Jiang H , et al. Green electrospun grape seed extract-loaded silk fibroin nanofibrous mats with excellent cytocompatibility and antioxidant effect[J]. Colloids and Surfaces B-Biointerfaces, 2016,139(1):56.
[12]
WeiY L, Sun D, Yi H G , et al. Characterization of a PEG-DE cross-linked tubular silk scaffold[J]. Textile Research Journal, 2014,84(9):959.
[13]
ZhouW, Feng Y, Yang J , et al. Electrospun scaffolds of silk fibroin and poly(lactide-co-glycolide) for endothelial cell growth[J]. Journal of Materials Science-Materials in Medicine, 2015,26(1):5386.
[14]
ErselM, Uyanikgil Y, Karbek Akarca F , et al. Effects of silk sericin on incision wound healing in a dorsal skin flap wound healing rat model[J]. Medical Science Monitor, 2016,22:1064.
[15]
GuanG, Wang L, Li M , et al. In vivo biodegradation of porous silk fibroin films implanted beneath the skin and muscle of the rat[J]. Biomedical Materials and Engineering, 2014,24(1):789.
[16]
LeeO J, Lee J M, Kim J H , et al. Biodegradation behavior of silk fibroin membranes in repairing tympanic membrane perforations[J]. Journal of Biomedical Materials Research Part A, 2012,100(8):2018.
[17]
LuQ, Zhang B, Li M , et al. Degradation mechanism and control of silk fibroin[J]. Biomacromolecules, 2011,12(4):1080.
[18]
GoslineJ M, Guerette P A, Ortlepp C S , et al. The mechanical design of spider silks: From fibroin sequence to mechanical function[J]. Journal of Experimental Biology, 1999,202(23):3295.
[19]
JiangC Y, Wang X Y, Gunawidjaja R , et al. Mechanical properties of robust ultrathin silk fibroin films[J]. Advanced Functional Materials, 2007,17(13):2229.
[20]
Ma Y, Li Z, Dai F Y , et al. A review on modification of silk and silk fabrics[J].Science of Sericulture, 2016(6):1106 (in Chinese).
HuangX S . Comparison and analysis of several degumming methods for silkworm cocoon extraction Guangxi Sericulture, 2009,46(4):1(in Chinese).
[23]
黄贤帅 . 桑蚕削口茧几种脱胶方法的比较分析[J]. 广西蚕业, 2009,46(4):1.
[24]
ZhangY Q . Comparative analysis of silk degumming methods Science of Sericulture, 2002,28(1):75(in Chinese).
[24]
张雨青 . 蚕丝脱胶方法的比较分析[J]. 蚕业科学, 2002,28(1):75.
[25]
YangM, Shuai Y, He W , et al. Preparation of porous scaffolds from silk fibroin extracted from the silk gland of Bombyx mori (B. mori)[J]. International Journal of Molecular Sciences, 2012,13(6):7762.
[26]
MaJ, Wang X Y, Li Q , et al. Study on methods of silk sericin recovery Journal of Anhui Agricultural Sciences, 2015,33(4):674(in Chinese).
YeC J, Li B, Meng Y , et al. Extraction of natural sericin and screening of its enzymatic hydrolysis conditions China Sericulture, 2015,36(4):44(in Chinese).
MeinelL, Fajardo R, Hofmann S , et al. Silk implants for the healing of critical size bone defects[J]. Bone, 2005,37(5):688.
[29]
RajkhowaR, Gil E S, Kluge J , et al. Reinforcing silk scaffolds with silk particles[J]. Macromolecular Bioscience, 2010,10(6):599.
[30]
MandalB B, Grinberg A, Gil E S , et al. High-strength silk protein scaffolds for bone repair[J]. Proceedings of The National Academy of Sciences of The United States of America USA, 2012,109(20):7699.
[31]
KuboyamaN, Kiba H, Arai K , et al. Silk fibroin-based scaffolds for bone regeneration[J]. Journal of biomedical materials research Part B-Applied Biomaterials, 2013,101(2):295.
[32]
FossC, Merzari E, Migliaresi C , et al. Silk fibroin/hyaluronic acid 3D matrices for cartilage tissue engineering[J]. Biomacromolecules, 2013,14(1):38.
[33]
YamamotoK, Tomita N, Fukuda Y , et al. Time-dependent changes in adhesive force between chondrocytes and silk fibroin substrate[J]. Biomaterials, 2007,28(10):1838.
[34]
LiX, He J, Bian W , et al. A novel silk-based artificial ligament and tricalcium phosphate/polyether ether ketone anchor for anterior cruciate ligament reconstruction-safety and efficacy in a porcine model[J]. Acta Biomaterialia, 2014,10(8):3696.
[35]
LiX, He J K, Bian W G , et al. A novel silk-TCP-PEEK construct for anterior cruciate ligament reconstruction:An off the shelf alternative to a bone-tendon-bone autograft[J]. Biofabrication, 2014,6(1):015010.
[36]
VachirarojN, Ratanavaraporn J, Damrongsakkul S , et al. A comparison of Thai silk fibroin-based and chitosan-based materials on in vitro biocompatibility for bone substitutes[J]. International Journal of Biological Macromolecules, 2009,45(5):470.
[37]
WangL, Lu C X, Li Y H , et al. Green fabrication of porous silk fibroin/graphene oxide hybrid scaffolds for bone tissue engineering[J]. RSC Advances, 2015,5(96):78660.
[38]
ShiL Y . Preparation and properties of hydroxyapatite-silk firoin/chitosan composite scaffolds[D]. Hangzhou:Zhejiang University, 2014(in Chinese).
AltmanG H, Horan R L, Lu H H , et al. Silk matrix for tissue engineered anterior cruciate ligaments[J]. Biomaterials, 2002,23(20):4131.
[40]
ShenW, Chen X, Chen J , et al. The effect of incorporation of exogenous stromal cell-derived factor-1 alpha within a knitted silk-collagen sponge scaffold on tendon regeneration[J]. Biomaterials, 2010,31(28):7239.
[41]
ChenX, Qi Y Y, Wang L L , et al. Ligament regeneration using a knitted silk scaffold combined with collagen matrix[J]. Biomaterials, 2008,29(27):3683.
[42]
FanH, Liu H, Wong E J , et al. In vivo study of anterior cruciate ligament regeneration using mesenchymal stem cells and silk scaffold[J]. Biomaterials, 2008,29(23):3324.
[43]
LiuH, Ge Z, Wang Y , et al. Modification of sericin-free silk fibers for ligament tissue engineering application[J]. Journal of Biomedical Materials Research Part B-Applied Biomaterials, 2007,82(1):129.
[44]
ShiP, Teh T K, Toh S L , et al. Variation of the effect of calcium phosphate enhancement of implanted silk fibroin ligament bone integration[J]. Biomaterials, 2013,34(24):5947.
[45]
YagiT, Sato M, Nakazawa Y , et al. Preparation of double-raschel knitted silk vascular grafts and evaluation of short-term function in a rat abdominal aorta[J]. Journal of Artificial Organs, 2011,14(2):89.
[46]
WangJ W, Li X D, Wei G F . Cell co-culture technology accelerates premicrovascular-like structure formation Journal of Clinical Rehabilitative Tissue Engineering Research, 2013,17(38):6779(in Chinese).
LiuH, Li X, Zhou G , et al. Electrospun sulfated silk fibroin nanofibrous scaffolds for vascular tissue engineering[J]. Biomaterials, 2011,32(15):3784.
[48]
YanS Q, Zhang Q, Wang J N , et al. Silk fibroin/chondroitin sulfate/hyaluronic acid ternary scaffolds for dermal tissue reconstruction[J]. Acta Biomaterialia, 2013,9(6):6771.
[49]
HanF, Liu S, Liu X , et al. Woven silk fabric-reinforced silk nanofibrous scaffolds for regenerating load-bearing soft tissues[J]. Acta Biomaterialia, 2014,10(2):921.
[50]
HanF, Li H B, Li L H, Qian Y N , et al. Preparation and cytocompatibility study of poly(ε-caprolactone)/silk sericin nanofibrous scaffolds[J]. Journal of Biomedical Engineering, 2011(2):305 (in Chinese).
YooC R, Yeo I S, Park K E , et al. Effect of chitin/silk fibroin nanofibrous bicomponent structures on interaction with human epidermal keratinocytes[J]. International Journal of Biological Macromolecules, 2008,42(4):324.
[52]
NayakS, Dey S, Kundu S C . Skin equivalent tissue-engineered construct: Co-cultured fibroblasts/keratino-cytes on 3D matrices of sericin hope cocoons[J]. Plos One, 2013,8(9):e74779.
[53]
XuY, Zhang Z, Chen X , et al. A silk fibroin/collagen nerve scaffold seeded with a co-culture of schwann cells and adipose-derived stem cells for sciatic nerve regeneration[J]. Plos One, 2016,11(1):e0147184.
[54]
LiG, Kong Y, Zhao Y , et al. Fabrication and characterization of polyacrylamide/silk fibroin hydrogels for peripheral nerve regeneration[J]. Journal of Biomaterials Science-Polymer Edition, 2015,26(14):899.
[55]
WeiY, Gong K, Zheng Z , et al. Chitosan/silk fibroin-based tissue-engineered graft seeded with adipose-derived stem cells enhances nerve regeneration in a rat model[J]. Journal of Materials Science-Materials in Medicine, 2011,22(8):1947.
[56]
WangC Y, Zhang K H, Fan C Y , et al. Aligned natural-synthetic polyblend nanofibers for peripheral nerve regeneration[J]. Acta Biomaterialia, 2011,7(2):634.
[57]
Maghdouri-White Y, Bowlin G L, Lemmon C A , et al. Mammary epithelial cell adhesion, viability, and infiltration on blended or coated silk fibroin-collagen type I electrospun scaffolds[J]. Materials Science & Engineering C-Materials for Biological Applications, 2014,43:37.
[58]
CritchfieldA S, McCabe R, Klebanov N , et al. Biocompatibility of a sonicated silk gel for cervical injection during pregnancy: In vivo and in vitro study[J]. Reproductive Sciences, 2014,21(10):1266.
[59]
KasojuN, Bora U . Silk fibroin based biomimetic artificial extracellular matrix for hepatic tissue engineering applications[J]. Biomedical Materials, 2012,7(4):45004.
[60]
ChungE J, Ju H W, Park H J , et al. Three-layered scaffolds for artificial esophagus using poly(epsilon-caprolactone) nanofibers and silk fibroin: An experimental study in a rat model[J]. Journal of Biomedical Materials Research Part A, 2015,103(6):2057.
[61]
GallerK M, D'Souza R N . Tissue engineering approaches for regenerative dentistry[J]. Regenerative Medicine, 2011,6(1):111.
[62]
HarkinD G, George K A, Madden P W , et al. Silk fibroin in ocular tissue reconstruction[J]. Biomaterials, 2011,32(10):2445.
[63]
XueH J, Liu L, Hu D D , et al. Fabrication and property test of chitosan/silk fibroin composite films with low swelling ratio Science of Sericulture, 2011,37(6):1073(in Chinese).
Lu C, Zhang J, Wang Y F , et al. Research progress of the preparation methods of silk fibroin microsphere[J].Progress in Textile Science & Technology, 2016(9):1(in Chinese).
GuZ P, Xie H X, Huang C C , et al. Preparation of chitosan/silk fibroin blending membrane fixed with alginate dialdehyde for wound dressing[J]. International Journal of Biological Macromolecules, 2013,58:121.
[66]
HouZ M . Study on preparation and properties of chitin / silk fibroin composite medical biological dressing[D]. Zhejiang Sci-Tech University, 2008,25(2):141(in Chinese).
InpanyaP, Faikrua A, Ounaroon A , et al. Effects of the blended fibroin/aloe gel film on wound healing in streptozotocin-induced diabetic rats[J]. Biomedical Materials, 2012,7(3):35008.
[68]
ShahverdiS, Hajimiri M, Esfandiari M A , et al. Fabrication and structure analysis of poly(lactide-co-glycolic acid)/silk fibroin hybrid scaffold for wound dressing applications[J]. International Journal of Pharmaceutics, 2014,473(1-2):345.
[69]
KanokpanontS, Damrongsakkul S, Ratanavaraporn J , et al. An innovative bi-layered wound dressing made of silk and gelatin for accelerated wound healing[J]. International Journal of Pharmaceutics, 2012,436(1-2):141.
[70]
KanokpanontS, Damrongsakkul S, Ratanavaraporn J , et al. Physico-chemical properties and efficacy of silk fibroin fabric coated with different waxes as wound dressing[J]. International Journal of Biological Macromolecules, 2013,55(2):88.
[71]
LiL H . Fabricaion of electrospun silk protein based composite nanofibers and their relevant applicaion[D]. Chongqing:Chongqing University, 2015(in Chinese).
ChenL, Zhu Y B, Li Y Y , et al. Progress and prospect of electrospun silk fibroin in construction of tissue-engineering scaffold Chinese Journal of Biotechnology, 2011,27(6):831(in Chinese).
LiS, Shi X Y, Lin W , et al. Repairing peripheral nerve defects in rats by electrostatic spinning poly (lactic-co-glycolic acid)-silk fibroin-collagen nerve conduits Chinese Journal of Tissue Engineering Research, 2012,16(38):7087(in Chinese).
CaiJ Y, Wang C Y, Fan C Y . Progress in the study of nerve conduits containing silk fibroin in nerve tissue engineering International Journal of Orthopaedics, 2015,36(6):394 (in Chinese).
MandalB B, Kundu S C . Calcium alginate beads embedded in silk fibroin as 3D dual drug releasing scaffolds[J]. Biomaterials, 2009,30(28):5170.
[76]
XieM B, Fan D, Chen Y F , et al. An implantable and controlled drug-release silk fibroin nanofibrous matrix to advance the treatment of solid tumour cancers[J]. Biomaterials, 2016,103:33.