Fabrication of chitosan based nanofibers mat with highly hemostatic function

구본강,박상준,김민섭,진용재,김천호 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0

Fabrication and characterization of highly aligned nanofiber scaffolds with conductivity for use as tissue engineering applications

구본강,박상준,김천호 한국고분자학회 2017 한국고분자학회 학술대회 연구논문 초록집 Vol.42 No.2

1P-188 The beneficial effect on cell infiltration and viability on porous chitosan nanofiber scaffolds

구본강,박상준,김천호 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

Chitosan has attracted considerable interest owing to its advantageous biological properties such as non-toxic, antibacterial, biodegradable and biocompatible. In this study, we fabricated the porous chitosan nanofiber scaffolds using electrospinning and ultra-sonication for tissue engineering application. The basic characterization such as surface morphology, mechanical properties, and wettability of porous chitosan nanofiber scaffolds were performed. In addition, the cell infiltration and viability of normal human dermal fibroblasts cultured on the porous chitosan nanofiber scaffolds in vitro were found to be excellent. These results suggest that the porous chitosan nanofiber scaffolds has great potential for use as tissue engineering applications.

AMR 기반 저 전력 인공 대역 확장 기술 개발

구본강,박희완,주연재,강상원,Koo, Bon-Kang,Park, Hee-Wan,Ju, Yeon-Jae,Kang, Sang-Won 한국음향학회 2011 韓國音響學會誌 Vol.30 No.4

대역폭 확장 (Bandwidth Extension)은 300-3400 Hz 대역의 협대역 음성 신호를 50-7000 Hz 대역의 광대역 음성신호로 확장하여 협대역 음성신호의 음질과 명료도를 높이는 기술이다. 본 논문에서는 협대역 음성 정보만을 이용해서 광대역 음성신호를 추정하는 인공 대역폭 확장 기술을 설계하여, ITU-T 협대역 표준 음성 코덱인 AMR (adaptive multi-rate) 복호화기에 내장시킴 (embedded)으로써, 대역폭 확장 모듈에서의 LPC 분석 및 LSP 해석과 관련된 계산량을 감소시켰고, 알고리즘 지연도 줄였다. 그리고 SDS (single distance search) 고속 탐색 방식을 대역폭 확장 시스템의 코드북 매핑에 적용하여, 최종적으로 저 전력 대역 확장 AMR 복호화기를 설계하였다. 제안된 대역폭 확장 방법은 AMR 복호화기 후단에 독립적으로 설치되는 기존 DTE (decode then extend)방식에 비해 28 % 정도의 계산량을 줄이고 알고리즘 지연도 20 msec 줄였다. 또한 제안방식은 피치정보를 이용한 classified 코드북 매핑 방식을 사용하여 스펙트럼 포락선을 확장하였고, 코드 벡터 탐색 시 가중치를 적용하여 광대역 합성 음성의 성능을 향상시켰다. Bandwidth extension is a technique to improve speech quality and intelligibility, extending from 300-3400 Hz narrowband speech to 50-7000 Hz wideband speech. This paper designs an artificial bandwidth extension (ABE) module embedded in the AMR (adaptive multi-rate) decoder, reducing LPC/LSP analysis and algorithm delay of the ABE module. We also introduce a fast search codebook mapping method for ABE, and design a low power BWE technique based on the AMR decoder. The proposed ABE method reduces the computational complexity and the algorithm delay, respectively, by 28 % and 20 msec, compared to the traditional DTE (decode then extend) method. We also introduce a weighted classified codebook mapping method for constructing the spectral envelope of the wideband speech signal.

전도성 고분자를 이용한 바이오센서

구본강,진용재,박상준,김천호 한국생체재료학회 2011 생체재료학회지 Vol.15 No.1

A biosensor is an analytical device which converts a biological response into an electrical signal. Recently, conducting polymers have received great attention in the development of biosensors. Conducting polymer is emerging materials with potential for biosensors because of their chemical sensitivity and biocompatibility. The conducting polymers are known to endow with abundance special features, which allow them to act as superior materials for immobilization of biomolecules and rapid response time for the fabrication of efficient biosensors. Conducting polymer, such as films,nanowires, as sensing platforms for application are also summarized in electrochemical and field effect transistor (FET)biosensor.

재료 Poster 발표 : Fe2O3 고체환원에 의한 제품화 연구

구본강,박병희,이해수 한국화학공학회 1994 춘계학술발표회 Vol.- No.-

고분자 나노 섬유 형상 조절을 위한 변형된 전기방사

구본강(Bon-Kang Gu),구경완Kyung-Wan Koo) 호서대학교 공업기술연구소 2011 공업기술연구 논문집 Vol.30 No.1

전기방사 기술은 높은 전기장에서 고분자용액으로부터 연속적인 나노섬유를 얻을 수 있는 방법이다. 그러나 금속 주사기 니들로부터 방출된 고분자 용액은 강한 전기장에 의한 위핑(whipping) 운동으로 수집기에 매우 불규칙한 형태로 수집된다. 그러므로, 통상적인 전기방사를 하는 동안에 나노섬유의 형상을 조절하는 것은 매우 어렵다. 본논문에서는 변형된 전기방사 장치를 이용하여 여러 가지 다양한 방법을 통해 나노섬유의 형상 조절에 대해 소개하 고자 한다. 이러한 변형된 전기방사장치로 인해 얻어진 나노섬유는 다양한 분야에서 응용이 될 것으로 기대된다. The electrospinnmg technology enables the production of continuous polymer nanofibers rrom polymer solutions or melts in high applied electric fields. However, the electrospun nanofibers are usually randomly deposited on the collector by the whipping motion of the jet ejected from a syringe needle containing the polymeric solution. Therefore, difficulties arise for the precise control of their shape on the nano-scale during electrospinning. This paper introduced various kinds of nanofibers having different shapes by modifying the electrospinning system. This will certainly enhance the performance of products made frcan nanofibers and allow application specific modifications.

In Vitro Evaluation of Lysyl Oxidase Antibody Conjugated Nanoparticles

김민섭,박상준,구본강,신현진,이기호,김상범,김천호 한국고분자학회 2016 Macromolecular Research Vol.24 No.8

In this study, we prepared poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) conjugated to lysyl oxidase-inhibiting antibodies (LOXab) as an anticancer therapy in order to efficiently inhibit the growth of mammary cancer cells. Scanning electron microscopy and dynamic light scattering analysis showed that the antibody-conjugated NPs tested were stable and round, with a mean diameter of 165 nm and surface charge of -15 mV, compared with values of 143 nm and -17 mV for pristine NPs. The pristine NPs at concentrations less than 1,000 ug/ml showed low cytotoxicity and were effectively internalized into cancer cells. Our in vitro studies showed that the LOXab conjugated NPs were two to three times more suppressive of lung, colorectal and breast cancer cells than was the soluble antibody at the same dose. Taken together, our results suggest that NPs conjugated to LOXab constitute a promising nano-therapeutic candidate for inhibiting the growth of mammary cancer cells.

Collagen/poly(d,l-lactic-co-glycolic acid) composite fibrous scaffold prepared by independent nozzle control multi-electrospinning apparatus for dura repair

박해관,주원일,구본강,하미연,유수정,전흥재 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.66 No.-

The objective of the present study was to evaluate non-woven collagen/poly(lactic-co-glycolic acid) fibrous scaffold (Col/PLGA FS) prepared by a co-electrospinning process using a novel multi syringe electrospinning system for dura repair. The morphological and mechanical properties of the fibrous scaffolds (FSs) were assessed by scanning electron microscopy (SEM) and a universal testing machine (UTM). The changes in chemical composition due to the incorporation of collagen into PLGA were determined by Fourier transform infrared spectroscopy-attenuated total reflection mode (FTIR-ATR). The biocompatibility of the FSs was also evaluated in vitro in cultures of mouse fibroblasts and in vivo by subcutaneous implantation studies in rats. SEM images of the samples showed that the fiber size distribution of Col/PLGA FS became narrow compared to that of PLGA FS due to the incorporation of collagen with small fiber diameter. The FTIR-ATR spectrum of Col/PLGA FS revealed the characteristic bands of collagen and PLGA, indicating the co-existence of two fibrous structures. The poor mechanical properties of collagen FS were improved by co-electrospinning with PLGA. In vitro L929 cell proliferation assay revealed that the cyto-compatibility of Col/PLGA FS was increased compared to that of PLGA FS. In addition, Col/PLGA FS showed increased hydrophilic properties sufficient to absorb the exudates at the interface with mild foreign body reactions. In animal studies using a traumatic brain injury (TBI) model, the incorporation of collagen induced increased macrophage chemotaxis, and the post-inflammatory reaction of these cells led to remarkable brain tissue regeneration.

Effect of the pore size in a 3D bioprinted gelatin scaffold on fibroblast proliferation

최동진,박상준,구본강,김영진,정석,김천호 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.67 No.-

Significant efforts have been applied toward fabricating three-dimensional (3D) scaffolds using 3D-bioprinting tissue engineering techniques. Gelatin has been used in 3D-bioprinting to produce designed 3D scaffolds; however, gelatin has a poor printability and is not useful for fabricating desired 3D scaffolds using 3D-bioprinting. In this study, we fabricated pore size controlled 3D gelatin scaffolds with two step 3D-bioprinting approach: a low-temperature (−10 °C) freezing step and a crosslinking process. The scaffold was crosslinked with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The pore sizes of the produced 3D gelatin scaffolds were approximately 30% smaller than the sizes of the designed pore sizes. The surface morphologies and pore sizes of the 3D gelatin scaffolds were confirmed and measured using scanning electron microscopy (SEM). Human dermal fibroblasts (HDFs) were cultured on a 3D gelatin scaffold to evaluate the effect of the 3D gelatin scaffold pore size on the cell proliferation. After 14 days of culture, HDFs proliferation throughout the 3D gelatin scaffolds prepared with more than 580 μm pore size was approximately 14% higher than proliferation throughout the 3D gelatin scaffold prepared with a 435 μm pore size. These results suggested that control over the 3D gelatin scaffold pore size is important for tissue engineering scaffolds.