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Poly(ethylene terephthalate) (PET) texture was exposed to oxygen plasma glow discharge to produce peroxides on its surfaces. These peroxides were then used as catalysts for the polymerization of acrylic acid (AA) in order to prepare a PET introduced by a carboxylic acid group (PET-A). Chitosan and quaternized chitosan (QC) were then coupled with the carboxyl groups on the PET-A to obtain chitosan-grafted PET (PET-A-C) and QC-grafted PET (PET-A-QC), respectively. These surface-modified PETs were characterized by attenuated total reflection Fourier transform IR spectroscopy, electron spectroscopy for chemical analysis, and a contact angle goniometer. The amounts of AA, chitosan, and QC grafted on the PET surfaces as determined by the gravimetric method were about 6, 8, and 9 g/cm 2 , respectively. The antibacterial activity of the surface-modified PET textures was investigated using a shake flask method. After 6 h of shaking, the growth of bacteria was markedly inhibited by PET with ionically (86% in PET-A Ϫ -C ϩ ) and covalently (75% in PET-A-C) grafted chitosan and with covalently grafted QC (83% in PET-A-QC). After the laundering the inhibition of the growth of the bacteria was maintained in the range of 48 -58%, showing the fastness of the chitosan-grafted PET textures against laundering.

The blood compatibility of poly(ethylene oxide) (PEO)-grafted and heparin (Hep) immobilized polyurethanes was investigated using in vitro plasma recalcification time (PRT), activated partial thromboplastin time (APTT), platelet adhesion and activation, and peripheral blood mononuclear cell (PBMC) adhesion and activation. In the experiment with plasma proteins, the PRT of the polyurethane (PU) surface was prolonged by PEO grafting and further prolonged by heparin immobilization. The APTT was prolonged on PU-Hep, suggesting the binding of immobilized heparin to antithrombin III. The percentage of platelet adhesion on PU was not much different from that on acrylic acid- and PEO-grafted PUs (PU-C, PU-6, PU-33), yet was substantially decreased by heparin immobilization (PU-6-Hep, PU-33-Hep). The release of serotonin from adhering platelets was slightly suppressed on PEO-grafted PUs yet significantly suppressed on heparin-immobilized PUs. In the PBMC experiments, the adhesion and activation of the cells were significantly suppressed on heparin-immobilized PUs, and the amount of interleukin-6 (IL-6) released from PBMCs stimulated with surface-modified PUs decreased with a decrease in PBMC adhesion.

초록: 루틴은 항발암, 소염제, 항바이러스성 기능을 갖는 물질이다. 미생물이 만들어낸 폴리에스테르인 PHBV와 루틴 을 전기방사하여 나노섬유 부직포를 얻었다. 나노섬유 부직포의 항균성은 황색포도상구균(Staphylococcus aureus), 폐 렴간균(Klebsiella pneumoniae)을 사용하여 평가하였고, KB 셀을 이용하여 세포독성을 평가하였다. 그 결과 루틴을 3 wt% 함유할 때 지지체는 우수한 항균성을 보였으며, KB 셀을 이용한 실험결과로부터 루틴을 함유하는 PHBV 지지체 는 세포독성을 나타내지 않음을 알 수 있었다.Abstract: Rutin(R) exhibits a wide range of biological activities including anticarcinogenic, antiinflammatory and antiviral actions. The purpose of this study is to investigate the effect of rutin concentrations (1 and 3 wt%) on the antibacterial activity of poly(3-hydroxybutylate-co-hydroxyvalerate)(PHBV) scaffolds. Antibacterial activity was evaluated by using Staphylococcus aureus and Klebsiella pneumoniae. Furthermore, the qualitative ongrowth of human KB endothelial cells was done to study in vitro cytotoxicity of the scaffolds. As the results, PHBV scaffolds containing 3 wt% rutin completely inhibited the proliferation of Staphylococcus aureus and Klebsiella pneumoniae. In addition, the PHBV/R scaffolds used in this study did not show any cytotoxicity when evaluated them with KB endothelial cells.

-Poly(m-phenyleneisophthalamide), m-aramid has no adjacent α-hydrogen of a nitrogen-halogen bond causes dehydrohalogenation. This fact proposes that m-aramid is one of good antimicrobial precursors. To enhance the surface area of m-aramid, electrospinning was employed. Scanning electron microscopy(SEM) was conducted to inspect the morphology change of m-aramid. The surface area of regular and electrospun m-aramid was calculated. Swatch test was applied to measure antimicrobial activity of the samples. The results showed that within 10 min contact time the electrospun m-aramid inactivated Escherichia coli KCTC 1039 (Gram-negative bacteria) with 8 log reductions.

Microcapsules of alginate cross-linked with divalent cations are the most common system for cell immobilization. In this work, the polyion complex (PIC) microcapsules were made using sodium alginate/barium chloride as the wall materials and gelatin/poly (vinyl alcohol) (PVA) as the extracellular matrices. The result of the permeability experiment of microcapsules using proteins with different molecular weight showed that the capsule has a molecular weight cut-off (MWCO) of 150 kDa. The hepatocytes encapsulated in microcapsules with gelatin and PVA in the core rapidly aggregated as incubation time increased. The aggregated hepatocytes showed high ammonia removal and albumin synthesis, showing a high potential for use in a bio artificial liver system.

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