为获得一种具有优良生物相容性,能够用于伤口敷料的纤维材料,以细菌纤维素为原料,以氯化锂/二甲基乙酰胺为溶剂体系制备纺丝液,以水为凝固浴,采用湿法纺丝技术制备再生细菌纤维素纤维,进而以环丙沙星为模型药物对再生细菌纤维素纤维进...为获得一种具有优良生物相容性,能够用于伤口敷料的纤维材料,以细菌纤维素为原料,以氯化锂/二甲基乙酰胺为溶剂体系制备纺丝液,以水为凝固浴,采用湿法纺丝技术制备再生细菌纤维素纤维,进而以环丙沙星为模型药物对再生细菌纤维素纤维进行载药整理,制得一种可用于伤口敷料的载药纤维。通过X射线衍射、力学性能、载药性、释药性等测试对再生细菌纤维素纤维进行表征。结果表明:纤维直径约为40μm,表面呈沟槽结构,力学强度可达2.5 c N/dtex;细菌纤维素再生后,晶型发生了改变,从纤维素Ⅰ型转化成纤维素Ⅱ型,且结晶度从66.3%降低至36.2%;载药和释药结果显示,再生细菌纤维素纤维在碱性条件下载药量最高,载药纤维在酸性条件下释药量最高。展开更多
In this work,we describe a novel facile method to prepare long one-dimensional hybrid nanofibers by using hydrated bacterial cellulose nanofibers(BCF)as a template.Silver(Ag)nanoparticles with an average diameter of 1...In this work,we describe a novel facile method to prepare long one-dimensional hybrid nanofibers by using hydrated bacterial cellulose nanofibers(BCF)as a template.Silver(Ag)nanoparticles with an average diameter of 1.5 nm were well dispersed on BCF via a simple in situ chemical-reduction between AgNO3and NaBH4at a relatively low temperature.A growth mechanism is proposed that Ag nanoparticles are uniformly anchored onto BCF by coordination with BC-containing hydroxyl groups.The bare BCF and as-prepared Ag/BCF hybrid nanofibers were characterized by several techniques including transmission electron microscopy,X-ray diffraction,thermogravimetric analyses,and ultraviolet-visible(UV-Vis)absorption spectra.The antibacterial properties of Ag/BCF hybrid nanofibers against Escherichia coli(E.coli,Gram-negative)and Staphylococcu saureus(S.saureus,Gram-positive)bacteria were evaluated by using modified Kirby Bauer method and colony forming count method.The results show that Ag nanoparticles are well dispersed on BCF surface via in situ chemical-reduction.The Ag/BCF hybrid nanofiber presents strong antibacterial property and thus offers its candidature for use as functional antimicrobial agents.展开更多
The pretreatment of rice straw is often used to enhance the hydrolysis. 1-allyl-3-methylimidazolium chloride （ [ AMIM ] C1） is a kind of low viscous, nontoxic and recyclable ionic liquid. It was used to treat rice s...The pretreatment of rice straw is often used to enhance the hydrolysis. 1-allyl-3-methylimidazolium chloride （ [ AMIM ] C1） is a kind of low viscous, nontoxic and recyclable ionic liquid. It was used to treat rice straw and improve the enzymatic hydrolysis of rice straw in this study. The factors influencing the pretreatment were as follows： the dosage of rice straw in [ AMIM ] Cl, crush mesh of rice straw, pretreatment temperature and time. After the pretreatment with a 3 % （the weight ratio of rice straw to ionic liquid） rice straw dosage in [AMIM]Cl at 110 ℃ for 1 h, the yield of reducing sugar of regenerated rice straw by 33 U/mL cellulase hydrolysis was 53.3 %, which was two times higher than that of un-treated rice straw （23.7 % ）. More researches regarding straw biorefinery to bacterial cellulose are being performed in the lab and prospective results will be published in near future.展开更多
The energy crisis and environmental pollution are serious challenges that humanity will face for the long-term. Despite tremendous efforts, the development of environmentally friendly methods to fabricate new energy m...The energy crisis and environmental pollution are serious challenges that humanity will face for the long-term. Despite tremendous efforts, the development of environmentally friendly methods to fabricate new energy materials is still challenging. Here we report, for the first time, a new strategy to fabricate various doped carbon nanofiber （CNF） aerogels by pyrolysis of bacterial cellulose （BC） pellicles which had adsorbed or were dyed with different toxic organic dyes. The proposed strategy makes it possible to remove the toxic dyes from waste-water and then synthesize doped CNF aerogels using the dyed BC pellicles as precursors. Compared with other reported processes for preparing heteroatom doped carbon （HDC） nanomaterials, the present synthetic method has some significant advantages, such as being green, general, low-cost and easily scalable. Moreover, the as-prepared doped CNF aerogels exhibit great potential as electrocatalysts for the oxygen reduction reaction （ORR） and as electrode materials for supercapacitors.展开更多
文摘为获得一种具有优良生物相容性,能够用于伤口敷料的纤维材料,以细菌纤维素为原料,以氯化锂/二甲基乙酰胺为溶剂体系制备纺丝液,以水为凝固浴,采用湿法纺丝技术制备再生细菌纤维素纤维,进而以环丙沙星为模型药物对再生细菌纤维素纤维进行载药整理,制得一种可用于伤口敷料的载药纤维。通过X射线衍射、力学性能、载药性、释药性等测试对再生细菌纤维素纤维进行表征。结果表明:纤维直径约为40μm,表面呈沟槽结构,力学强度可达2.5 c N/dtex;细菌纤维素再生后,晶型发生了改变,从纤维素Ⅰ型转化成纤维素Ⅱ型,且结晶度从66.3%降低至36.2%;载药和释药结果显示,再生细菌纤维素纤维在碱性条件下载药量最高,载药纤维在酸性条件下释药量最高。
基金Supported by the National Natural Science Foundation of China（21206076） the Natural Science Foundation of Jiangsu Province（BK2012401 and BK2011715） National High Technology Research and Development Program of China（2011AA050701）
文摘In this work,we describe a novel facile method to prepare long one-dimensional hybrid nanofibers by using hydrated bacterial cellulose nanofibers(BCF)as a template.Silver(Ag)nanoparticles with an average diameter of 1.5 nm were well dispersed on BCF via a simple in situ chemical-reduction between AgNO3and NaBH4at a relatively low temperature.A growth mechanism is proposed that Ag nanoparticles are uniformly anchored onto BCF by coordination with BC-containing hydroxyl groups.The bare BCF and as-prepared Ag/BCF hybrid nanofibers were characterized by several techniques including transmission electron microscopy,X-ray diffraction,thermogravimetric analyses,and ultraviolet-visible(UV-Vis)absorption spectra.The antibacterial properties of Ag/BCF hybrid nanofibers against Escherichia coli(E.coli,Gram-negative)and Staphylococcu saureus(S.saureus,Gram-positive)bacteria were evaluated by using modified Kirby Bauer method and colony forming count method.The results show that Ag nanoparticles are well dispersed on BCF surface via in situ chemical-reduction.The Ag/BCF hybrid nanofiber presents strong antibacterial property and thus offers its candidature for use as functional antimicrobial agents.
基金Science and Technology Commission of Shanghai Municipality (No.11230700600No.08520750200)+2 种基金Shanghai Municipal Education Commission (No.09ZZ68)the "111 " Project(No.B07024)the Fundamental Research Funds for the Central Universities and Key Laboratory of Science &Technology of Eco-Textile (Donghua University),Ministry of Education (No.Eco-op-2009-09)
文摘The pretreatment of rice straw is often used to enhance the hydrolysis. 1-allyl-3-methylimidazolium chloride （ [ AMIM ] C1） is a kind of low viscous, nontoxic and recyclable ionic liquid. It was used to treat rice straw and improve the enzymatic hydrolysis of rice straw in this study. The factors influencing the pretreatment were as follows： the dosage of rice straw in [ AMIM ] Cl, crush mesh of rice straw, pretreatment temperature and time. After the pretreatment with a 3 % （the weight ratio of rice straw to ionic liquid） rice straw dosage in [AMIM]Cl at 110 ℃ for 1 h, the yield of reducing sugar of regenerated rice straw by 33 U/mL cellulase hydrolysis was 53.3 %, which was two times higher than that of un-treated rice straw （23.7 % ）. More researches regarding straw biorefinery to bacterial cellulose are being performed in the lab and prospective results will be published in near future.
基金This work is supported by the Ministry of Science and Technology of China （Grants 2010CB934700, 2013CB933900, 2014CB931800）, the National Natural Science Foundation of China （Grants 21431006, 91022032, 91227103, 21061160492, J1030412）, the Chinese Academy of Sciences （Grant KJZD-EW- M01-1）, and Hainan Province Science and Technology Department （CXY20130046） for financial support. We thank Ms. C. Y. Zhong for kindly providing purified bacterial cellulose pellicles.
文摘The energy crisis and environmental pollution are serious challenges that humanity will face for the long-term. Despite tremendous efforts, the development of environmentally friendly methods to fabricate new energy materials is still challenging. Here we report, for the first time, a new strategy to fabricate various doped carbon nanofiber （CNF） aerogels by pyrolysis of bacterial cellulose （BC） pellicles which had adsorbed or were dyed with different toxic organic dyes. The proposed strategy makes it possible to remove the toxic dyes from waste-water and then synthesize doped CNF aerogels using the dyed BC pellicles as precursors. Compared with other reported processes for preparing heteroatom doped carbon （HDC） nanomaterials, the present synthetic method has some significant advantages, such as being green, general, low-cost and easily scalable. Moreover, the as-prepared doped CNF aerogels exhibit great potential as electrocatalysts for the oxygen reduction reaction （ORR） and as electrode materials for supercapacitors.
