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Cheng G, Wang X, Wu M, Wu S, Cheng L, Zhang X, Dai F. Insignificant Difference in Biocompatibility of Regenerated Silk Fibroin Prepared with Ternary Reagent Compared with Regenerated Silk Fibroin Prepared with Lithium Bromide. Polymers (Basel) 2022; 14:polym14183903. [PMID: 36146047 PMCID: PMC9502819 DOI: 10.3390/polym14183903] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 09/11/2022] [Accepted: 09/13/2022] [Indexed: 11/16/2022] Open
Abstract
Bombyx mori silk fibroin (SF) is widely used in the field of biomaterials due to its excellent biocompatibility and mechanical properties. However, SF cannot be used directly in many applications and needs to be dissolved first. Lithium bromide (LiBr) is a traditional solvent which is usually used to dissolve SF. However, LiBr has several limitations, e.g., it is expensive, it is toxic to organisms, and it is environmentally unfriendly. Herein, we investigate the possibility of developing a ternary reagent system that is inexpensive, non-toxic to organisms, and environmentally friendly as an alternative for silk fibroin solubilization. The results confirm that regenerated silk fibroin (RSF) prepared using a ternary reagent has the same morphology and amino acid composition as that prepared using LiBr, but the RSF prepared using a ternary reagent still had a small amount of calcium residue even after long-term dialysis. Further research found that the residual calcium does not cause significant differences in the structure and biological performance of the RSF, such as its cytotoxicity, blood compatibility, and antibacterial properties. Therefore, we believe that ternary reagents are an ideal alternative solvent for dissolving SF.
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Affiliation(s)
- Guotao Cheng
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Sericulture & Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Xin Wang
- Center for Joint Surgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Mengqiu Wu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Sericulture & Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Siyuan Wu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Sericulture & Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Lan Cheng
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Sericulture & Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Xiaoning Zhang
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Sericulture & Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
| | - Fangyin Dai
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Sericulture & Textile and Biomass Sciences, Southwest University, Chongqing 400715, China
- Correspondence:
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Chen S, Ciou JH, Yu F, Chen J, Lv J, Lee PS. Molecular-Level Methylcellulose/MXene Hybrids with Greatly Enhanced Electrochemical Actuation. Adv Mater 2022; 34:e2200660. [PMID: 35584538 DOI: 10.1002/adma.202200660] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 05/15/2022] [Indexed: 06/15/2023]
Abstract
Ti3 C2 Tx MXene film is promising for electrochemical actuators due to its high electrical conductivity and volumetric capacitance. However, its actuation performance is limited by the slow ion diffusion through the film and poor mechanical property in aqueous electrolytes. Here, molecular-level methylcellulose (MC)/MXene hybrid films are assembled with obviously enlarged layer distance, improved wet strength, and ambient stability. The hybrid films show significantly higher in-plane actuation strain in a liquid electrolyte. Based on direct strain measurements, in situ X-ray diffraction (XRD) and ex situ X-ray photoelectron spectroscopy (XPS) analyses, the actuation enhancement can be ascribed to the enlarged layer distance allowing more water and ions to be intercalated/de-intercalated and MC-induced sliding of MXene sheets. The assembled soft actuator has a high Young's modulus of 1.93 GPa and can be operated in air, generating a peak-to-peak strain difference up to 0.541% under a triangular wave voltage of ±1 V and a blocking force of 4.7 times its own weight.
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Affiliation(s)
- Shaohua Chen
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Jing-Hao Ciou
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Fei Yu
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Jian Chen
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Jian Lv
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Pooi See Lee
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
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Zhou HY, Yan SS, Li J, Dong H, Zhou P, Wan L, Chen XX, Zhang WL, Xia YC, Wang PC, Wang BG, Liu K. Lithium Bromide-Induced Organic-Rich Cathode/Electrolyte Interphase for High-Voltage and Flame-Retardant All-Solid-State Lithium Batteries. ACS Appl Mater Interfaces 2022; 14:24469-24479. [PMID: 35587195 DOI: 10.1021/acsami.2c05016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Poly(ethylene oxide) (PEO)-based solid electrolyte suffers from limited anodic stability and an intrinsic flammable issue, hindering the achievement of high energy density and safe all-solid-state lithium batteries. Herein, we surprisingly found out that a bromine-rich additive, decabromodiphenyl ethane (DBDPE), could be preferably oxidized at an elevated voltage and decompose to lithium bromide at an elevated potential followed by inducing an organic-rich cathode/electrolyte interphase (CEI) on NCM811 surface, enabling both high-voltage resistance (up to 4.5 V) and flame-retardancy for the PEO-based electrolyte. On the basis of this novel solid electrolyte, all-solid-state Li/NCM811 batteries deliver an average reversible capacity of 151.4 mAh g-1 over the first 150 cycles with high capacity retention (83.0%) and high average Coulombic efficiency (99.7%) even at a 4.5 V cutoff voltage with a unprecedented flame-retardant properties. In view of these exploration, our studies revealed the critical role of LiBr in inducing an organic-rich thin and uniform CEI passivating layer with enhanced lithium ion surface diffusion and high-voltage resistant properties, which provides a new protocol for the further design of a high-voltage PEO-based all-solid-state electrolyte.
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Affiliation(s)
- Hang-Yu Zhou
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Shuai-Shuai Yan
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Jun Li
- Sinopec Shanghai Research Institute of Petrochemical Technology, Shanghai 201208, China
| | - Hao Dong
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Pan Zhou
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Lei Wan
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Xiao-Xia Chen
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Wei-Li Zhang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Ying-Chun Xia
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Pei-Can Wang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Bao-Guo Wang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Kai Liu
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
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Yang X, Li Z, Li L, Li N, Jing F, Hu L, Shang Q, Zhang X, Zhou Y, Pan X. Depolymerization and Demethylation of Kraft Lignin in Molten Salt Hydrate and Applications as an Antioxidant and Metal Ion Scavenger. J Agric Food Chem 2021; 69:13568-13577. [PMID: 34730357 DOI: 10.1021/acs.jafc.1c05759] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
To improve the reactivity and enrich the functionality of lignin for valorization, kraft lignin was depolymerized and demethylated via cleaving aryl and alkyl ether bonds in acidic lithium bromide trihydrate (∼60% LiBr aqueous solution). It was found that the cleavage of the ether bonds followed the order of β-O-4 ether > aryl alkyl ether in phenylcoumaran > dialkyl ether in resinol > methoxyl (MeO). The depolymerization via β-O-4 cleavage occurred under mild conditions (e.g., <0.5 M HCl at 110 °C), while sufficient demethylation of the lignin needed harsher conditions (>1.5 M HCl). Both depolymerization and demethylation generated new aromatic hydroxyl (ArOH). With 2.4 M HCl, MeO content dropped from 4.85 to 0.95 mmol/g lignin, and ArOH content increased from 2.78 to 5.09 mmol/g lignin. The depolymerized and demethylated kraft lignin showed excellent antioxidant activity and Cr(VI)-scavenging capacity, compared with original kraft lignin and tannins.
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Affiliation(s)
- Xiaohui Yang
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Dongxiaofu-1 Xiangshan Road, Beijing 100091, China
| | - Zheng Li
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
| | - Long Li
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Ning Li
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
| | - Fei Jing
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Lihong Hu
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Dongxiaofu-1 Xiangshan Road, Beijing 100091, China
| | - Qianqian Shang
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Xiao Zhang
- Center for Bioproducts and Bioenergy, Washington State University, 2710 University Drive, Richland, Washington 99354, United States
| | - Yonghong Zhou
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Xuejun Pan
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
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Gao W, Wei X, Chen J, Jin J, Wu K, Meng W, Wang K. Recycling Lithium from Waste Lithium Bromide to Produce Lithium Hydroxide. Membranes (Basel) 2021; 11:membranes11100759. [PMID: 34677525 PMCID: PMC8538373 DOI: 10.3390/membranes11100759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 11/16/2022]
Abstract
Lithium resources face risks of shortages owing to the rapid development of the lithium industry. This makes the efficient production and recycling of lithium an issue that should be addressed immediately. Lithium bromide is widely used as a water-absorbent material, a humidity regulator, and an absorption refrigerant in the industry. However, there are few studies on the recovery of lithium from lithium bromide after disposal. In this paper, a bipolar membrane electrodialysis (BMED) process is proposed to convert waste lithium bromide into lithium hydroxide, with the generation of valuable hydrobromic acid as a by-product. The effects of the current density, the feed salt concentration, and the initial salt chamber volume on the performance of the BMED process were studied. When the reaction conditions were optimized, it was concluded that an initial salt chamber volume of 200 mL and a salt concentration of 0.3 mol/L provided the maximum benefit. A high current density leads to high energy consumption but with high current efficiency; therefore, the optimum current density was identified as 30 mA/cm2. Under the optimized conditions, the total economic cost of the BMED process was calculated as 2.243 USD·kg−1LiOH. As well as solving the problem of recycling waste lithium bromide, the process also represents a novel production methodology for lithium hydroxide. Given the prices of lithium hydroxide and hydrobromic acid, the process is both environmentally friendly and economical.
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Affiliation(s)
- Wenjie Gao
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
| | - Xinlai Wei
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
- Anhui Key Laboratory of Sewage Purification and Eco-Restoration Materials, Hefei 230088, China
- Correspondence:
| | - Jun Chen
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
- Anhui Key Laboratory of Sewage Purification and Eco-Restoration Materials, Hefei 230088, China
| | - Jie Jin
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
- Anhui Key Laboratory of Sewage Purification and Eco-Restoration Materials, Hefei 230088, China
| | - Ke Wu
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
- Anhui Key Laboratory of Sewage Purification and Eco-Restoration Materials, Hefei 230088, China
| | - Wenwen Meng
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
| | - Keke Wang
- Collaborative Innovation Center for Environmental Pollution Control and Ecological Restoration of Anhui Province, School of Biology, Food and Environment, Hefei University, Hefei 230601, China; (W.G.); (J.C.); (J.J.); (K.W.); (W.M.); (K.W.)
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Yang B, Jiang H, Zhou Y, Liang Z, Zhao T, Lu YC. Critical Role of Anion Donicity in Li 2S Deposition and Sulfur Utilization in Li-S Batteries. ACS Appl Mater Interfaces 2019; 11:25940-25948. [PMID: 31246006 DOI: 10.1021/acsami.9b07048] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Lithium-sulfur batteries offer a high theoretical gravimetric energy density and low cost, but the full utilization of the sulfur electrode has been limited by the premature passivation of insulating lithium sulfide (Li2S). Anion has been one of the major parameters to improve Li-S batteries in addition to solvent, additives, and electrode structures. Here, we reveal the role of anion donicity on the passivation of Li-S battery and its underlying working mechanism. We show that anions with high donicity effectively reduce the charge-transfer resistance during the cycling of Li-S cells and alleviate the Li2S passivation by transforming the dense film Li2S to porous three-dimensional flake Li2S. UV-vis spectroscopy revealed that anions with higher donicity exhibit higher Li2S4 solubility, which is consistent with their stronger bonding to Li+, as revealed by nuclear magnetic resonance and density functional theory calculations. Our study reveals the role of anion donicity in Li2S passivation and its underlying mechanism, offering rational design consideration for electrolyte salts in achieving high sulfur utilization and high energy efficiency for Li-S batteries.
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Affiliation(s)
- Bin Yang
- Electrochemical Energy and Interfaces Laboratory, Department of Mechanical and Automation Engineering , The Chinese University of Hong Kong , Shatin , N.T. 999077 Hong Kong SAR , China
| | - Haoran Jiang
- HKUST Energy Institute, Department of Mechanical and Aerospace Engineering , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon 999077 , Hong Kong SAR , China
| | - Yucun Zhou
- Electrochemical Energy and Interfaces Laboratory, Department of Mechanical and Automation Engineering , The Chinese University of Hong Kong , Shatin , N.T. 999077 Hong Kong SAR , China
| | - Zhuojian Liang
- Electrochemical Energy and Interfaces Laboratory, Department of Mechanical and Automation Engineering , The Chinese University of Hong Kong , Shatin , N.T. 999077 Hong Kong SAR , China
| | - Tianshou Zhao
- HKUST Energy Institute, Department of Mechanical and Aerospace Engineering , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon 999077 , Hong Kong SAR , China
| | - Yi-Chun Lu
- Electrochemical Energy and Interfaces Laboratory, Department of Mechanical and Automation Engineering , The Chinese University of Hong Kong , Shatin , N.T. 999077 Hong Kong SAR , China
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Yang X, Li N, Lin X, Pan X, Zhou Y. Selective Cleavage of the Aryl Ether Bonds in Lignin for Depolymerization by Acidic Lithium Bromide Molten Salt Hydrate under Mild Conditions. J Agric Food Chem 2016; 64:8379-8387. [PMID: 27744686 DOI: 10.1021/acs.jafc.6b03807] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The present study demonstrates that the concentrated lithium bromide (LiBr) solution with acid as catalyst was able to selectively cleave the β-O-4 aryl ether bond and lead to lignin depolymerization under mild conditions (e.g., in 60% LiBr with 0.3 M HCl at 110 °C for 2 h). Four industrial lignins from different pulping and biorefining processes, including softwood kraft lignin (SKL), hardwood kraft lignin (HKL), softwood ethanol organosolv lignin (EOL), and acid corncob lignin (ACL), were treated in the LiBr solution. The molecular weight, functional group, and interunit linkages of the lignins were characterized using GPC, FTIR, and NMR. The results indicated that the β-O-4 aryl ether bonds of the lignins were selectively cleaved, and both LiBr and HCl played crucial roles in catalyzing the cleavage of the ether bonds.
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Affiliation(s)
- Xiaohui Yang
- Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry , Nanjing 210042, China
- Department of Biological Systems Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Ning Li
- Department of Biological Systems Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Xuliang Lin
- Department of Biological Systems Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Xuejun Pan
- Department of Biological Systems Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Yonghong Zhou
- Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry , Nanjing 210042, China
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Abstract
Silk fibroin protein was purified from Bombyx mori silkworm cocoons using a novel dialysis strategy to avoid fibroin aggregation and pre-mature formation of β-sheets. The degummed silk fibers were dissolved in Ajisawa's reagent, a mixture of CaCl2-EtOH-H2O, that is less expensive than lithium bromide. The dissolved solutions were dialyzed against either water or urea solution with a stepwise decrease in concentration. When the steps of 4 M-2 M-1 M-0 M urea (referred to as silk-TS-4210) were adopted, the purified silk fibroin had smaller aggregates (<10 nm), similar average molecular weight (225 kDa) and a lower content of β-sheet (∼15%) compared to the sample processing methods (silk-TS-210, 10, 0) studied here. This outcome was close to the fibroin purified by the lithium bromide (silk-Li-0) method. Polyvinyl alcohol-emulsified silk microspheres generated using the purified solution had a similar size distribution and morphology when compared to lithium bromide dissolved solutions, while glycerol-blended silk films showed different mechanical properties. The silk-Li-0 generated films with the highest breaking strength (5.7 MPa ± 0.3) while the silk-TS-4210 had the highest extension at break (215.1% ± 12.5). The films prepared from silk-TS-4210 were cytocompatible to support the adhesion and proliferation of human mesenchymal stem cells, with improvements compared to the other samples likely due to the porous morphology of these films.
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Affiliation(s)
- Zhaozhu Zheng
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
| | - Shaozhe Guo
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
| | - Yawen Liu
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
| | - Jianbing Wu
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
| | - Gang Li
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
| | - Meng Liu
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
| | - Xiaoqin Wang
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, China
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