지식나눔

bacterial cellulose 특성 분석

안녕하세요. bacterial cellulose 특성 분석에 관하여 전문가분들에게 여쭤보고 싶은게 많네요.

bacterial cellulose 분자량 분석시 보통 GPC를 이용한다고 하는데... cellulose자체가 THF용매에 녹지가 않아 GPC 분석에 애로점이 많습니다.
어떻게 해야 하는지요?????
그리고 중합도는 어떻게 구하는건지 여쭤보고싶습니다.

XRD분석은 어떻게 해야하는지요???? 이 또한 분말을 만들어 분석을 의뢰하였었는데... 찍히질 않는다고 하는데...

cellulose 분석을 해보신 분들에게 조언을 부탁드립니다.

감사합니다.
 
  • bacteria cellulose
  • 분자량
  • 중합도
지식의 출발은 질문, 모든 지식의 완성은 답변! 
각 분야 한인연구자와 현업 전문가분들의 답변을 기다립니다.
답변 3
  • 답변

    이배훈님의 답변

    THF는 주로 합성고분자용 GPC 용매입니다.

     cellulose용 용매(ionic liquid 등) 포함된 수용성 용매를 사용해야할 것 같습니다.

    참고박사논문이 있어 첨부하였습니다. (여러 분석 방법을 참고하시면 될 것 같습니다.)

    3.2.11. Determination of average polymerization degree (DP) 
    The DP of cellulose was measured with cupri-ethylene-diamine (CED) methods according to ISO 5351/1:1981, with iron (III) sodium tartrate complex solution (EWNN mod NaCl method) and with GPC (Gel Permeation Chromatography). 
    1) Method in cupri-ethylene-diamine (CED) solution 
    25 ml of the cupri-ethylene-diamine solution were mixed with 25 ml of distilled water. After 
    thermal stabilization at 25 oC, the viscosity of a solvent was measured. The expected viscosity was about 550 ml/g. Chosen concentration of cellulose solution is 0.0025 g/ml. 25ml of distilled water was added to a sample, together with 2 g of copper. It was shaken until the samples has been completely disintegrated. Then 25 ml of CED solution was added, and this was shaken for 2 h, and put in the constant-temperature bath until the temperature of 25±0.1 oC has been
    3.Experimental part

    2) Method in EWNN- solution 
    EWNN was prepared first with using of ferric chloride hexahydrate (FeCl3*6H2O), sodium 
    tartrate dehydrate [Na2(C4H4O6)2H2O], sodium hydroxide solution, containing 96.0 g of sodium hydroxide (NaOH) per 180 ml of water.

    첨부 논문 중에서
    THF는 주로 합성고분자용 GPC 용매입니다.

     cellulose용 용매(ionic liquid 등) 포함된 수용성 용매를 사용해야할 것 같습니다.

    참고박사논문이 있어 첨부하였습니다. (여러 분석 방법을 참고하시면 될 것 같습니다.)

    3.2.11. Determination of average polymerization degree (DP) 
    The DP of cellulose was measured with cupri-ethylene-diamine (CED) methods according to ISO 5351/1:1981, with iron (III) sodium tartrate complex solution (EWNN mod NaCl method) and with GPC (Gel Permeation Chromatography). 
    1) Method in cupri-ethylene-diamine (CED) solution 
    25 ml of the cupri-ethylene-diamine solution were mixed with 25 ml of distilled water. After 
    thermal stabilization at 25 oC, the viscosity of a solvent was measured. The expected viscosity was about 550 ml/g. Chosen concentration of cellulose solution is 0.0025 g/ml. 25ml of distilled water was added to a sample, together with 2 g of copper. It was shaken until the samples has been completely disintegrated. Then 25 ml of CED solution was added, and this was shaken for 2 h, and put in the constant-temperature bath until the temperature of 25±0.1 oC has been
    3.Experimental part

    2) Method in EWNN- solution 
    EWNN was prepared first with using of ferric chloride hexahydrate (FeCl3*6H2O), sodium 
    tartrate dehydrate [Na2(C4H4O6)2H2O], sodium hydroxide solution, containing 96.0 g of sodium hydroxide (NaOH) per 180 ml of water.

    첨부 논문 중에서
    등록된 댓글이 없습니다.
  • 답변

    김상태님의 답변

    액체 기반 셀룰로오스 용액은 1-ethyl-3-methylimidazolium acetate([C2mim]OAc)을 사용하여
    조제할수 있다.
    Toledo 대학교의 Schall 교수는 이온성 액체로 Avicel 셀룰로오스를 전처리하여 cellulase 효소(from T. reesei)로 가수분해시킨 결과, 글루코오스 수율을 약 2배 가량 향상시킬 수 있다. 이온성 액체 [C4mim]Cl로 전처리한 결과, Avicel 셀룰로오스의 결정성이 크게 약화되었음을 XRD 분석을 통하여 확인 가능함
    액체 기반 셀룰로오스 용액은 1-ethyl-3-methylimidazolium acetate([C2mim]OAc)을 사용하여
    조제할수 있다.
    Toledo 대학교의 Schall 교수는 이온성 액체로 Avicel 셀룰로오스를 전처리하여 cellulase 효소(from T. reesei)로 가수분해시킨 결과, 글루코오스 수율을 약 2배 가량 향상시킬 수 있다. 이온성 액체 [C4mim]Cl로 전처리한 결과, Avicel 셀룰로오스의 결정성이 크게 약화되었음을 XRD 분석을 통하여 확인 가능함
    등록된 댓글이 없습니다.
  • 답변

    김상태님의 답변

     XRD analysis was performed accordingly . In detail, Synchrotron X-ray diffraction experiments were performed on a six-circle diffractometer (Huber 5020) in the Beijing Synchrotron Radiation Facility Center using CuKα radiation with a wave length of λ = 0.154 nm. An X-ray beam with a photon energy of 8.051 keV was focused on the plant samples. X-ray diffractograms were collected by a scintillator detector Huber9910 that was set at a distance of 45 mm from the sample.
    PLoS Genet. Aug 2013; 9(8): e1003704.
    Published online Aug 22, 2013. doi:  10.1371/journal.pgen.1003704
    PMCID: PMC3749933

    Brittle Culm1, a COBRA-Like Protein, Functions in Cellulose Assembly through Binding Cellulose Microfibrils

     XRD analysis was performed accordingly . In detail, Synchrotron X-ray diffraction experiments were performed on a six-circle diffractometer (Huber 5020) in the Beijing Synchrotron Radiation Facility Center using CuKα radiation with a wave length of λ = 0.154 nm. An X-ray beam with a photon energy of 8.051 keV was focused on the plant samples. X-ray diffractograms were collected by a scintillator detector Huber9910 that was set at a distance of 45 mm from the sample.
    PLoS Genet. Aug 2013; 9(8): e1003704.
    Published online Aug 22, 2013. doi:  10.1371/journal.pgen.1003704
    PMCID: PMC3749933

    Brittle Culm1, a COBRA-Like Protein, Functions in Cellulose Assembly through Binding Cellulose Microfibrils

    등록된 댓글이 없습니다.