• 폴리머
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• 제38권4호
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• pp.449-456
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• 2014

Ternary blends of poly(L-lactic acid) (PLLA), poly(${\varepsilon}$-caprolactone) (PCL) and polyethylene oxide (PEO) were produced with different concentrations of components via melt blending. By leaching the PEO from the samples by water, porous materials were obtained with potential application for bio scaffolds. Sample porosity was evaluated by calculating the ratio of porous scaffold density (${\rho}^*$) to the non-porous material density (${\rho}_s$). Highest porosity (51.42%) was related to the samples containing 50 wt%. of PEO. Scanning electron microscopy (SEM) studies showed the best porosity resulted by decreasing PLLA/PCL ratio at constant concentration of PEO. Crystallization behavior of the ternary blend samples was studied using differential scanning calorimetry (DSC). Results revealed that the crystallinity of PLLA was improved by addition of PEO and PCL to the samples. The porosity plays a key role in governing the compression properties. Mechanical properties are presented by Gibson-Ashby model.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3377-3380
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• 2014

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.159-160
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• 2006

A novel approach to the manufacture of biocompatible ceramic scaffold for tissue engineering using micro-stereolithography system is introduced. Micro-stereolithography is a newly proposed technology that enables to make a 3D micro structure. The 3D micro structures made by this technology can have accurate and complex shape within a few micron error. Therefore, the application based on this technology can vary greatly in nano-bio fields. Recently, tissue-engineering techniques have been regarded as alternative candidate to treat patients with serious bone defects. So many techniques to design and fabricate 3D scaffolds have been developed. But the imperfection of scaffold such as random pore size and porosity causes a limitation in developing optimum scaffold. So scaffold development with controllable pore size and fully interconnected shape have been needed for a more progress in tissue engineering. In this paper, bone scaffold was developed by applying the micro-stereolithography to the mold technology. The scaffold material used was HA(Hydroxyapatite) nano powder. HA is a type of calcium phosphate ceramic with similar characteristic to human inorganic bone component. The bone scaffold made by HA is expected, in the near future, to be an efficient therapy for bone defect.

• 한국방사선학회논문지
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• 제17권6호
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• pp.993-999
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• 2023

피브리노겐 그리고 콜라겐의 생채재료는 조직재생공학에 널리 사용되고 있다. 이번 연구에서는 이 두 가지 재료를 사용하여 새로운 이중구조지지체를 만들고자 한다. 전략적으로 조직재생은 혈관 재생이 우선이기 때문에 혈관형성에 도움을 주는 피브리노겐 지지체를 이중지지체의 외부로 형성시키고 중앙에는 조직재생에 더욱 더 효과 있는 콜라겐을 위치시킴으로써 새로운 조직 재생의 상승효과를 기대하고 한다. 전례 연구에서는 이 두 가지 재료를 혼용해서 사용하고는 있지만 아직까지 중심구조(Core)시스템의 지지체 구조의 형성으로 지지체를 만들어 보고된 바는 없다. 따라서 이번 연구의 핵심인 이중지지체는 내부는 콜라겐 지지체 외부는 피브리노겐을 위치시킨 중심(Core) 구조 제조 방법을 제시하고자 한다. 실험결과는 이중구조지지체의 전략적인 생분해(Biodegradation)에 기인하여 지지체의 외부에 위치한 피브리노겐은 빠른 생분해와 약물방출이 발생했다. 반면 콜라겐 지지체는 상대적으로 피브리노겐지지체 보다는 약물의 방출 시간을 오래 유지할 수 있는 결과를 보았다. 결론적으로 이중 지지체를 만드는 방법을 적용한다면 결손 조직재생에 상승효과가 있을 것으로 사료된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1259-1264
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• 2007

Microstereolithography technology has potential capability for fabrication of 3D microstructures. It evolved from conventional SLA which is one of the RP processes. In a microstereolithography process, 3D microstructures can be easily fabricated by continuously stacking 2D layer which is photopolymerized using a liquid prepolymer. Combination between biocompatible/biodegradable photocurable prepolymer and 3D complex fabrication in microstereolithography makes broad application areas such as medical, pharmaceutic, and bio devices. In particular, a 3D microneedle for transdermal drug delivery and a scaffold for tissue engineering are fabricated using this technology. In this paper, the authors address development of microstereolithography system adapted to large surface and fabrication of various microstructures. In addition, to apply human body we suggest a biodegradable 3D microneedle and a scaffold using biodegradable photocurable prepolymer.

• International Journal of Precision Engineering and Manufacturing
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• 제9권2호
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• pp.81-83
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• 2008

The Rapid Prototyping (RP) technology has advanced in many application areas. In this research, two different types, cylinder and scaffold, of implantable Drug Delivery System (DDS) were fabricated using Nano Composite Deposition System (NCDS), one of the RP systems. The anti-cancer drug (5-fluorouracil, 5-FU), biodegradable polymer (PLGA(85: 15)), and bio ceramic (Hydroxyapatite, HA) were used to form drug-polymer composite material. Both types of DDS were evaluated in vivo environment for two weeks. For evaluation, the cumulative drug release and shape stability were measured. Test results showed that the scaffold DDS provide higher cumulative drug release and has better stability than cylinder DDS.

• Quantitative Bio-Science
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• 제37권2호
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• pp.113-124
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• 2018

Pim kinases are important targets for cancer therapies because they are mainly responsible for cancer metastasis and overall therapeutic treatment responses. Because of their unusual structural feature in the hinge region of the ATP-binding site, new binding motifs have been discovered and used for the development of Pim kinases inhibitors. The results of a screening of 5-membered heteroaromatic compounds and the effects of structural modifications on the inhibition of Pim kinases' activities showed the potential scaffold for Pim inhibitors. 1,3,4-Oxadiazole-2(3H)-thione was found as a new scaffold for Pim kinase inhibitors.

• 한국정밀공학회지
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• 제31권12호
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• pp.1067-1076
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• 2014

To date, biomedical application of three-dimensional (3D) printing technology remains one of the most important research topics and business targets. A wide range of approaches have been attempted using various 3D printing systems with general materials and specific biomaterials. In this review, we provide a brief overview of the biomedical applications using 3D printing techniques, such as surgical tool, medical device, prosthesis, and tissue engineering scaffold. Compared to the other applications of 3D printed products, the scaffold fabrication should be performed with careful selection of bio-functional materials. In particular, we describe how the biomaterials can be processed into 3D printed scaffold and applied to tissue engineering area.

• Journal of Microbiology and Biotechnology
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• 제27권9호
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• pp.1664-1669
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• 2017

Gamma-aminobutyric acid is a precursor of nylon-4, which is a promising heat-resistant biopolymer. GABA can be produced from the decarboxylation of glutamate by glutamate decarboxylase. In this study, a synthetic scaffold complex strategy was employed involving the Neurospora crassa glutamate decarboxylase (GadB) and Escherichia coli GABA antiporter (GadC) to improve GABA production. To construct the complex, the SH3 domain was attached to the N. crassa GadB, and the SH3 ligand was attached to the N-terminus, middle, and C-terminus of E. coli GadC. In the C-terminus model, 5.8 g/l of GABA concentration was obtained from 10 g/l glutamate. When a competing pathway engineered strain was used, the final GABA concentration was further increased to 5.94 g/l, which corresponds to 97.5% of GABA yield. With the introduction of the scaffold complex, the GABA productivity increased by 2.9 folds during the initial culture period.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3471-3474
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• 2010