• 산업기술연구
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• 제21권B호
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• pp.27-30
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• 2001

For the development of a large-scale dialysis process for silk fibroin solution, a batch and continuous dialysis chamber was designed and built, which are to be used as a unit module for the process. A series of dialysis experiments were carried out to estimate the kinetic parameters for dialysis using the solutions of salt-solubilized silk fibroin. The solution was dialyzed by distilled water either batch-wise or continuously. Dialysis kinetics was monitored by measuring refractometery at high salt concentration and conductivity at lower salt concentration. The apparent dialysis coefficients were $5.4g/m^2-hr$ and $1.8g/m^2-hr$, for well mixed batch and continuous dialysis, respectively. The alteration of molecular weight distribution of dialyzed silk fibroin solution was monitored.

• 한국잠사곤충학회지
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• 제45권2호
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• pp.121-125
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• 2003

Dissolution of Antheraea pernyi silk fiber was carried out in a zinc nitrate 6 hydrate (Zn(NO$_3$)$_2$ㆍ6$H_2O$) solution with various dissolving conditions. The solubility was significantly dependent on the concentration of zinc nitrate, dissolving temperature and time. Regenerated A. pernyi silk fibroin powder was obtained through dialysis process to remove chaotropic salt. FTIR and X-ray diffractometer showed that the conformation of regenerated A. pernyi silk powder was sheet structure.

• 폴리머
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• 제38권1호
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• pp.98-102
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• 2014

실크 피브로인은 뛰어난 생체적합성 및 생분해성으로 인해 의료용 천연고분자소재로 각광받고 있으며 다양한 형태로 제조되어 이용되고 있다. 전기분사법은 고분자 용액에 고전압을 적용하여 미세입자를 제조하는 방법으로 진행과정이 간단하고 첨가제를 필요로 하지 않는다는 장점을 지닌다. 본 연구에서는 실크 피브로인 다공성 미세입자를 제조하기 위하여 폴리(에틸렌 글리콜)(PEG)을 첨가한 후 전기분사를 실시하였다. PEG를 첨가함으로써 분사원액의 전도도는 감소하였고 점도는 증가하였다. 제조된 미세입자의 크기는 PEG 첨가에 따라 감소하였는데 이는 분사용액의 전도도 및 점도보다는 피브로인과 PEG간의 상분리에 의한 효과인 것으로 보인다. 제조된 실크 피브로인 미세입자를 물에 침지한 결과 PEG가 제거되었으며 최종적으로 실크 피브로인 다공성 입자를 제조할 수 있었다. 제조된 다공성 실크 피브로인 미세입자는 약물전달체 및 조직공학용 세포전달체로 이용가능성이 높을 것으로 기대된다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.621-625
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• 2003

In order to investigate the properties of aqueous fibroin solution, the molecular weight distribution of silk fibroin was determined by gel filtration chromatography. The molecular weights spreaded from 200 kDa to less than 20 kDa. The distribution of molecular weight was significantly affected when the pH of solubilization solution is less than 1. Distributions of fibroin solution stored at various condition were also investigated.

• 한국잠사곤충학회지
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• 제39권1호
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• pp.67-72
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• 1997

As a condition for obtaining the silk I type crystal that has stability and high reproducibility, after dissolving silk fibroin crystalline part (Fcp), the changes of recrystallized crystal structure according to dialytic pH were examined by x-ray diffraction and differential thermal analysis. The Fcp was obtained from the aqueous solution of silk fibroin enzymatic proteolyzed by chymotrypsin. The crystal structure of Fcp showed silk II type. When the Fcp was dissolved by 10M LiBr aqueous solution, the Fcp1 showed the silk II type at pH 9. However, besides the silk II type, the silk I type structure begins to appear at pH 8 and only the silk I type structure was found below pH 6. On the other hand, the Fcp2 that calcium chloride was used in the dissolution found only the silk I type crystal structure below pH8.

• 한국잠사곤충학회지
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• 제46권1호
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• pp.28-31
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• 2004

견피브로인의 응용가능성을 높이기 위하여 대표적인 생체고분자인 히아론산을 이용하여 견피브로인/히아론산 브렌드 필름을 제조하였으며 구조 및 열 특성을 살펴보았다. 1. 적외선 분광분석 결과 견피브로인과 히아론산 두 고분자 사이에는 수소결합 등의 상호작용이 존재하지 않는 것으로 나타났다. 또한 브렌드 필름내에 존재하는 실크피브로인은 EDC 에탄올 용액처리에 의하여 $\beta$-sheet 구조로 전이되었다. 2. 견피브로인/히아론산 브렌드 필름에서 견피브로인과 히아론산 각각의 열분해 흡열피크와 발열피크 온도에는 큰 변화가 없었으나, 열분해 피크의 폭이 넓어지는 것으로 봐서 실크 피브로인과의 브렌드 또는 EDC 처리에 의하여 열분해 반응이 매우 복잡한 환경하에서 진행되고 있음을 알 수 있었다. 3 견피브로인/히아로산 브렌드 필름은 자기 중량 대비 평균 70배의 수분을 흡수하였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제45권2호
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• pp.70-77
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• 2022

Wet-spun regenerated silk fibroin (RSF) fibers have been extensively studied owing to their 1) useful properties as biomaterials, including good blood compatibility and cyto-compatibility; 2) the various methods available to control the structural characteristics and morphology of the fiber, and 3) the possibility of fabricating blended fibers and new material-embedded fibers. In this study, silk nanofibrils prepared using a new method were embedded in RSF to fabricate wet-spun silk nanofibril/RSF composite fibers. Up to 2% addition of silk nanofibril, the silk nanofibril/RSF dope solution showed slight shear thinning, and the G' and G" of the dope solution were similar. However, above 3% silk nanofibril content, the viscosity of the dope solution significantly increased. In addition, shear thinning was remarkably evident, and the G' of the dope solution was much higher than the G", indicating a very elastic state. As the silk nanofibril content was increased, the wet-spun silk nanofibril/RSF composite fiber became uneven, with a rough surface, and more beaded fibers were produced. Scanning electron microscopy observations revealed that the beaded fibers were attributed to the inhomogeneous dispersion and presence of agglomerates of the silk nanofibrils. As the silk nanofibril content and RSF concentration increased, the maximum draw ratio decreased, indicating the deterioration of the wet spinnability and post-drawing performance of silk nanofibril/RSF.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.798-799
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• 2001

The intermolecular hydrogen bond between silk fibroin in aqueous solution facilitates gelation of silk fibroin. The dependence of gelation by the concentration of silk fibroin, pH and temperature was investigated. The gelation time of silk fibroin is decreased with increasing the concentration of glycerol and temperature within a limited range. The pH optimum for gelation found out to be 9. Hydrophobic additives were investigated to reduce gelation time.

• 한국의류산업학회지
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• 제4권2호
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• pp.198-202
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• 2002

Degummed silk from Bombyx mori was dissolved in 9.3M lithium bromide solution. The regenerated silk fibroin films were completely ${\alpha}$-randomcoil type as shown by x-ray diffraction and infrared spectroscopy. The structural changes in silk fibroin induced by immersion into methanol and dilute hydrochloric acid and its photo-yellowing effect was studied. The changes of crystallinity were measured by infrared spectrometer. Yellowness index caused by ultraviolet irradiation were observed as a function of the structural change on silk fibroin. On treatment with methanol, ${\alpha}$-randomcoil silk film is converted to the ${\beta}$-form structure. After the treatment of hydrochloric acid on ${\beta}$-form structure in silk induced by immersion into methanol, ${\beta}$-form in silk fibroin is partially decreased. Crystallization owing to ${\beta}$-form transition reduced the initial yellowness index by ultraviolet irradiation. A little ${\beta}$-form structure in silk fibroin increased the initial yellowness in comparison with more ${\beta}$-form structure.

• 한국잠사곤충학회지
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• 제39권2호
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• pp.197-202
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• 1997

To hydrolyze silk fibroin was treated with NaOH solution on various concentrations and times. And it was examined that the addition effects of NaHSO3 solution on the solubility and colouring of silk fibroin. As obtained results are as follows; The more increasement of concentration and time of NaOH treatment, the more increasement of solubility but solubility was slight above 3% concentration of NaOH. Fibroin yield was decreased above 3% concentration. This was due to formation of peptide or amino acids below molecular weight 3,000. Most of molecular weight distribution came out to be under 3,000 in 2% concentration and 4hrs of NaOH treatment. The more increasement of adding concentration and 4hrs of NaOH treatment. The more increasement of adding concentration of NaHSO3, the more reduction of solubility but white index of powder increased. In the results of FT-IR spectras of silk fibroin powder obtained by various concentrations of NaHSO3 treatment, the absorbent peak at 3,400 cm-1 which was considered as -CH=N- (azomethine) was disappeared by the more addition of NaHSO3. It showed that absorbent peak of $\beta$-fibroin moved into low temperature region and transferred to $\alpha$- and random coil structure through the DSC experiment. In the results of amino acid analysis, alkali hydrolysis reduced the oxy amino contents acid like serine and tyrosine, but increased the glycine content by the more addition of NaHSO3.