• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.11a
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• pp.226-229
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• 2001

현재 초소형 정밀기계(MEMS;Microelectromechanical System) 소자의 가장 큰 문제점으로 대두되고 있는 점착현상을 방지하기 위하여 불화유기박막을 증착하였다. Octafluorocyclobutane(C$_4$F$_{8}$)을 소스가스를 PECVD (Plasma Enhanced CVD)와 ICP (Inductively Coupled Plasma)를 이용하여 증착하였다. 여기에 Ar을 첨가하여 플라즈마의 반응성을 높여주었다. 형성된 불화유기박막의 나노트라이볼러지 특성을 살펴보기 위하여 AFM을 통하여 증착시킨 시편의 topography를 살펴보았다. 그리고 박막의 antiadhesion의 정도를 살펴보기 위하여 cantilever와 박막의 표면 사이에 존재하는 interaction force를 측정 하였고 AFM의 force curve mode를 이용하였다 PECVB를 이용하여 증착된 박막은 ICP를 이용한 박막보다 균일하지 못한 박막을 보였으며 attractive force가 강한 것으로 사료된다.

• Natural Product Sciences
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• v.23 no.3
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• pp.175-182
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• 2017

This study evaluated the anti-Helicobacter and anti-inflammatory effects of Sohamhyungtang (SHHT). The minimum inhibitory concentration (MIC) of SHHT against Helicobacter pylori (H. pylori) was determined by the agar dilution method. Expression of the H. pylori cagA gene in the presence of SHHT was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Inhibition of H. pylori urease by SHHT was determined by the phenol-hypochlorite assay. Antiadhesion activity of SHHT was measured by urea-phenol red reagent. Inhibition of nitric oxide (NO) production in AGS cells was measured with Griess reagent. Inducible nitric oxide synthase (iNOS) and IL-8 mRNA expression in AGS cells which were infected with H. pylori was determined by qRT-PCR. IL-8 level was measured by enzyme-linked immunosorbent assay (ELISA). The MIC of SHHT was $100{\mu}g/mL$ and the expression of cagA gene was decreased about 25 folds in the presence of SHHT. H. pylori urease was inhibited 90% by SHHT. SHHT inhibited H. pylori adhesion on AGS cell in a concentration dependent manner. mRNA expression of iNOS and IL-8 and the production of NO and IL-8 were significantly decreased in the presence of SHHT. In conclusion, SHHT showed anti-Helicobacter activity and has potent anti-inflammatory effect on H. pylori-induced inflammation in human gastric epithelial AGS cells.

• Korean Journal of Materials Research
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• v.19 no.8
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• pp.437-442
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• 2009

This paper describes an improved strategy for controlling the adhesion force using both the antiadhesion and adhesion layers for a successful large-area transfer process. An MPTMS (3-mercaptopropyltrimethoxysilane) monolayer as an adhesion layer for Au/Pd thin films was deposited on Si substrates by vapor self assembly monolayer (VSAM) method. Contact angle, surface energy, film thickness, friction force, and roughness were considered for finding the optimized conditions. The sputtered Au/Pd ($\sim$17 nm) layer on the PDMS stamp without the anti-adhesion layer showed poor transfer results due to the high adhesion between sputtered Au/Pd and PDMS. In order to reduce the adhesion between Au/Pd and PDMS, an anti-adhesion monolayer was coated on the PDMS stamp using FOTS (perfluorooctyltrichlorosilane) after $O_2$ plasma treatment. The transfer process with the anti-adhesion layer gave good transfer results over a large area (20 mm $\times$ 20 mm) without pattern loss or distortion. To investigate the applied pressure effect, the PDMS stamp was sandwiched after 90$^{\circ}$ rotation on the MPTMS-coated patterned Si substrate with 1-${\mu}m$ depth. The sputtered Au/Pd was transferred onto the contact area, making square metal patterns on the top of the patterned Si structures. Applying low pressure helped to remove voids and to make conformal contact; however, high pressure yielded irregular transfer results due to PDMS stamp deformation. One of key parameters to success of this transfer process is the controllability of the adhesion force between the stamp and the target substrate. This technique offers high reliability during the transfer process, which suggests a potential building method for future functional structures.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.477-482
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• 2004

The aim of the present study was to investigate the efficacy of a mixed gel formulation composed of sodium carboxymethyl cellulose and gellan gum (Na-CMC gel) for the prevention of adhesions after laminectomy. The anti-adhesive effect of the Na-CMC gel was tested in a controlled randomized study using an animal model of lumbar laminectomy. The animals (60 female Sprague-Dawley rats) were randomly allocated into two treatment groups to receive the Na-CMC gel on the injured area or no gel (control). The incidence of adhesions and their grade were blindly evaluated at 4, 8 and 12 weeks after surgery. The amount of scar tissue and tenacity were grossly reduced by the Na-CMC gel at postoperative 4, 8, and 12 weeks. The mean adhesion scores were 0.75, 1.25, and 1.38 at 4, 8, and 12 weeks in the gel-treated group, respectively. No significant inflammatory reaction was observed and the healing of wound was not affected by the Na-CMC gel. The Na-CMC gel reduced the amount of scar formation and tenacity in rat laminectomy model without affecting the healing of operation wound and other complications. Therefore, the Na-CMC gel may be the potential to prevent postsurgical adhesions in clinical state.