Silkworm silks have been widely used in a variety of fields due to their sensuousness, luster and excellent mechanical properties. Researchers have paid special attention in improving the mechanical properties of silk...Silkworm silks have been widely used in a variety of fields due to their sensuousness, luster and excellent mechanical properties. Researchers have paid special attention in improving the mechanical properties of silks. In this work,Bombyx mori larval silkworms are injected with graphene quantum dots(GQDs) through a vascular injection to enhance mechanical properties of the silkworm silks. The GQDs can be incorporated into the silkworm silk gland easily due to hemolymph circulation and influence the spinning process of silkworm. The breaking strength, elongation at break and toughness modulus of the silks increase by 2.74, 1.33 and 3.62 times, respectively, by injecting per individual with 0.6 μg GQDs. Wide-angle X-ray scattering indicates that the size ofβ-sheet nanocrystals in GQDs-silks is smaller than that in control-silks. Infrared spectra suggest that GQDs confine the conformation transition of silk fibroin to β-sheet from random coil/α-helix, and the change of the size and content of β-sheet may be the reason for the improvement of the mechanical properties. The toxicity and safety limit of GQDs incorporated into each silkworm is also evaluated, and the results show that the upmost dose of GQDs per silkworm is30.0 μg. The successful obtainment of reinforced silks by in vivo uptake of GQDs provides a promising route to produce high-strength silks.展开更多
Spider silk has attracted increasing attention due to its fascinating combination of ultra-high tenacity high strength,and excellent elasticity.Based on the fundamental biological studies on spider silk,significant re...Spider silk has attracted increasing attention due to its fascinating combination of ultra-high tenacity high strength,and excellent elasticity.Based on the fundamental biological studies on spider silk,significant research efforts have been devoted to biotechnology and chemical synthesis to mimic or even exceed the properties of natural spider silk fibers.Moreover,the natural spider silk fiber has been simulated with the burgeoning development of numerous spinning technologies,including wet spinning,dry spinning,electrostatic spinning,and microfluidic spinning,which continuously help to optimize the properties of synthetic spider silk.The unique characteristics of natural spider silk include high refraction transmission,heat resistance,antimicrobial properties,biocompatibility,and super shrinking.Biconical recreation of spider silk with special features and extraordinary capabilities demonstrates potential applications in biomedicine,smart wearables,artificial muscles and sensors,aerospace and other domains.展开更多
The carotenoid composition of the silk tissue of Zea mays (L.) has not been investigated despite its large occurrence in maize grains. For the purpose of evaluating maize silk as a source of carotenoids, samples from ...The carotenoid composition of the silk tissue of Zea mays (L.) has not been investigated despite its large occurrence in maize grains. For the purpose of evaluating maize silk as a source of carotenoids, samples from eight landraces developed and cultivated in Southern Brazil were assayed. The silk samples were harvested from individual plants through the fourth and seventh day after they emerged, frozen in liquid N2, and lyophilized. The carotenoids were extracted with a MeOH/toluene solution (1:1, v/v), 30 min, and saponified (15% KOH, 12 h, 40℃). The RP-HPLC-UV-visible analysis revealed lutein as the main carotenoid (88.75%) in maize silks, with a wide range of contents (dry weight), i.e. 39.11 ?g?g-1 (Palha Roxa 18) to 176.12 ?g?g-1 (Língua de Papagaio) among the studied genotypes. Smaller amounts of trans-β-carotene, α-carotene, and zeaxanthin were also detected. The results revealed that in parallel to the claimed high genetic variability of maize landraces, a quite variable carotenoidic composition of silk tissue seems to occur in the germoplasm cultivated in Southern Brazil. Taking into account the usage of lutein for the prevention of several pathologies, especially the age related macular degeneration, some maize landraces (e.g. Língua de Papagaio and Rosado) might be interesting sources of a lutein-rich extract that could add value to an underutilized biomass.展开更多
Fluorescent polymer dots(Pdots)have the advantages of excellent optical properties,great biocompatibility and high photostability.Herein,we feed ultra-low doses Pdots to silkworms for the first time and aim to prepare...Fluorescent polymer dots(Pdots)have the advantages of excellent optical properties,great biocompatibility and high photostability.Herein,we feed ultra-low doses Pdots to silkworms for the first time and aim to prepare dual-performance modified silks.After Pdots feeding,the fluorescence signal of cocoons and degummed silks increases significantly,which is more stable and more uniform than that of post-treatment silks.Moreover,Pdots hinder the conformation transformation of silk fibroin and improve the mechanical property of twisted silk strand.The highest elongation at break point is 20.75±0.03% and breaking strength is 271.7±3.8 MPa.With excellent fluorescence and mechanical properties,the optimized silks are successfully applied as a scaffold for cell culture and imaging.Furthermore,we investigate the metabolism of Pdots in the silkworms for understanding the behaviours of Pdots in the process of silks synthesis and secretion.展开更多
基金supported by the Young Elite Scientist Sponsorship Program by CAST (2015QNRC001)the Earmarked Fund for Modern Agro-industry Technology Research System
文摘Silkworm silks have been widely used in a variety of fields due to their sensuousness, luster and excellent mechanical properties. Researchers have paid special attention in improving the mechanical properties of silks. In this work,Bombyx mori larval silkworms are injected with graphene quantum dots(GQDs) through a vascular injection to enhance mechanical properties of the silkworm silks. The GQDs can be incorporated into the silkworm silk gland easily due to hemolymph circulation and influence the spinning process of silkworm. The breaking strength, elongation at break and toughness modulus of the silks increase by 2.74, 1.33 and 3.62 times, respectively, by injecting per individual with 0.6 μg GQDs. Wide-angle X-ray scattering indicates that the size ofβ-sheet nanocrystals in GQDs-silks is smaller than that in control-silks. Infrared spectra suggest that GQDs confine the conformation transition of silk fibroin to β-sheet from random coil/α-helix, and the change of the size and content of β-sheet may be the reason for the improvement of the mechanical properties. The toxicity and safety limit of GQDs incorporated into each silkworm is also evaluated, and the results show that the upmost dose of GQDs per silkworm is30.0 μg. The successful obtainment of reinforced silks by in vivo uptake of GQDs provides a promising route to produce high-strength silks.
基金supported by the National Key Research and Development Program of China(Grant Nos.2019YFE0119600 and 2022YFA1203300)the National Natural Science Foundation of China(Grants 51973093,U1533122,and 51773094)+5 种基金"Frontiers Science Center for New Organic Matter",Nankai University,Tianjin,China(Grant No.63181206)the Science Foundation for Distinguished Young Scholars of Tianjin(Grant No.18JCJQJC46600)the Xingliao Talent Plan(XLYC1802042)Key Laboratory of Display Materials and Photoelectric Devices,Ministry of Education(LX20200420001)the Fundamental Research Funds for the Central Universities(Grant No.63171219)National Special Support Plan for High-level Talents people(C041800902).
文摘Spider silk has attracted increasing attention due to its fascinating combination of ultra-high tenacity high strength,and excellent elasticity.Based on the fundamental biological studies on spider silk,significant research efforts have been devoted to biotechnology and chemical synthesis to mimic or even exceed the properties of natural spider silk fibers.Moreover,the natural spider silk fiber has been simulated with the burgeoning development of numerous spinning technologies,including wet spinning,dry spinning,electrostatic spinning,and microfluidic spinning,which continuously help to optimize the properties of synthetic spider silk.The unique characteristics of natural spider silk include high refraction transmission,heat resistance,antimicrobial properties,biocompatibility,and super shrinking.Biconical recreation of spider silk with special features and extraordinary capabilities demonstrates potential applications in biomedicine,smart wearables,artificial muscles and sensors,aerospace and other domains.
文摘The carotenoid composition of the silk tissue of Zea mays (L.) has not been investigated despite its large occurrence in maize grains. For the purpose of evaluating maize silk as a source of carotenoids, samples from eight landraces developed and cultivated in Southern Brazil were assayed. The silk samples were harvested from individual plants through the fourth and seventh day after they emerged, frozen in liquid N2, and lyophilized. The carotenoids were extracted with a MeOH/toluene solution (1:1, v/v), 30 min, and saponified (15% KOH, 12 h, 40℃). The RP-HPLC-UV-visible analysis revealed lutein as the main carotenoid (88.75%) in maize silks, with a wide range of contents (dry weight), i.e. 39.11 ?g?g-1 (Palha Roxa 18) to 176.12 ?g?g-1 (Língua de Papagaio) among the studied genotypes. Smaller amounts of trans-β-carotene, α-carotene, and zeaxanthin were also detected. The results revealed that in parallel to the claimed high genetic variability of maize landraces, a quite variable carotenoidic composition of silk tissue seems to occur in the germoplasm cultivated in Southern Brazil. Taking into account the usage of lutein for the prevention of several pathologies, especially the age related macular degeneration, some maize landraces (e.g. Língua de Papagaio and Rosado) might be interesting sources of a lutein-rich extract that could add value to an underutilized biomass.
基金This study was supported by Grants from the National Natural Science Foundation of China(81974273,81671738,81301261 and 21374059)the National Key R&D Program of China(2016YFC1303100)the Shanghai Pujiang Project(13PJ1405000).
文摘Fluorescent polymer dots(Pdots)have the advantages of excellent optical properties,great biocompatibility and high photostability.Herein,we feed ultra-low doses Pdots to silkworms for the first time and aim to prepare dual-performance modified silks.After Pdots feeding,the fluorescence signal of cocoons and degummed silks increases significantly,which is more stable and more uniform than that of post-treatment silks.Moreover,Pdots hinder the conformation transformation of silk fibroin and improve the mechanical property of twisted silk strand.The highest elongation at break point is 20.75±0.03% and breaking strength is 271.7±3.8 MPa.With excellent fluorescence and mechanical properties,the optimized silks are successfully applied as a scaffold for cell culture and imaging.Furthermore,we investigate the metabolism of Pdots in the silkworms for understanding the behaviours of Pdots in the process of silks synthesis and secretion.
