This short review focuses on fouling by proteins and macromolecules in microfiltration/ultrafiltration. First, an experimental system that enables investigation of how the extent of the adsorption of proteins and macromolecules on membrane surfaces contributes to a decrease in filtrate flux in microfiltration/ultrafiltration is described. Using this system, a causal relationship - not a correlation - indicating that adsorption results in a decrease in filtrate flux could be clearly demonstrated in some cases. Second, a hydration structure at the membrane surface that can suppress adsorption is discussed, inspired by biomaterial research. In their hydrated states, polymers with low-fouling properties have water molecules with a particular structure. Finally, some successful examples of the development of low-fouling membranes via surface modification using low-fouling polymers are discussed.

Oocytes from small antral follicles (< 3 mm in diameter; SAFO) show lower developmental competence compared to those from medium antral follicles (3-8 mm in diameter; MAFO) in pigs. This study was designed to evaluate the effect of various macromolecules such as fetal bovine serum (FBS), porcine follicular fluid (PFF), bovine serum albumin (BSA) and polyvinyl alcohol (PVA) in in vitro growth (IVG) medium on oocyte growth, maturation, and embryonic development after parthenogenesis (PA). The base medium for IVG was α-MEM supplemented with dibutyryl cyclic AMP, pyruvate, kanamycin, hormone. This medium was further supplemented with 10% FBS, 10% PFF, 0.4% BSA, or 0.1% PVA. The in vitro maturation (IVM) medium was medium-199 supplemented with 10% PFF, cysteine, pyruvate, epidermal growth factor, kanamycin, insulin, and hormones. SAFO were cultured for 2 days for IVG and then cultured for 44 h for IVM. After IVG, the mean diameter of SAFO treated with FBS, PVA, and no IVG-MAFO (114.1, 113.0, and 114.8 μm, respectively) was significantly larger (P<0.01) than that of no IVG-SAF (111.8 μm). Oocyte diameter after IVM was greater (P<0.01) in SAFO treated with FBS, BSA and PVA (112.8, 112.9 and 112.6 μm, respectively) than other groups (110.4, 109.6, and 109.8 μm for no IVG-MAFO, no IVG-SAFO and PFF, respectively). Intraoocyte GSH content was not influenced by the macromolecules in IVG medium (0.92, 0.93, 1.05, and 1.12 pixels/oocyte for FBS, PFF, BSA and PVA, respectively). The proportion of oocytes reached the metaphase II stage was higher in PFF (73.6%) than in BSA (43.5%) and PVA (53.7%) but not different from that of FBS treatment (61.5%). The cumulus expansion score of oocytes after IVG was significantly influenced (P<0.01) by the macromolecules (2.94, 2.24, 1.84, and 1.38 for PFF, FBS, PVA, and BSA treatments, respectively). Blastocyst formation of PA oocytes that were treated with FBS (51.8%), PFF (50.4%), and PVA (45.2%) during IVG was higher (P<0.05) than that of BSA-treated oocytes (20.6%) but was not significantly different from that (54.8%) of no IVG-MAFO oocytes. Our results demonstrated that growth, maturation, and embryonic development of SAFO are greatly influenced by macromolecules in IVG medium and that PFF or FBS can be replaced with a chemically defined synthetic macromolecule PVA.

The objective of this study was to examine the effect of macromolecule in a maturation medium on nuclear maturation, intracellular glutathione (GSH) level of oocytes, and embryonic development after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT) in pigs. Immature pig oocytes were cultured in maturation medium that was supplemented with each polyvinyl alcohol (PVA), pig follicular fluid (pFF) or newborn calf serum (NBCS) during the first 22 h and the second 22 h. Oocyte maturation was not influenced by the source of macromolecules during in vitro maturation (IVM). Embryo cleavage and cell number in blastocyst after PA was altered by the source of macromolecule but no difference was observed in blastocyst formation among treatments. Oocytes matured in PVA-PVA medium showed lower rates of oocyte-cell fusion (70.4% vs. 7782%) and embryo cleavage (75% vs. 8690%) after SCNT than those matured in other media but blastocyst formation was not altered (1327%) by different macromolecules. pFF added to IVM medium significantly increased the intracellular GSH level of oocytes compared to PVA and NBCS, particularly when pFF was supplemented during the first 22 h of IVM. Our results demonstrate that source of macromolecule in IVM medium influences developmental competence of oocytes after PA and SCNT, and that pFF supplementation during the early period (first 22 h) of IVM increases intracellular GSH level of oocytes.

폴리비닐리덴풀루오라이드(Poly vinylidene fluoride, PVDF) 막을 고분자(Surface Modifying Macromolecules, SMM) 첨가제를 사용하여 표면 개질 하였다. 표면 개질된 PVDF 막의 제조는 0에서부터 2 wt%까지 SMM의 다양한 농도로 제조되었으며, 사용된 SMM으로써는 Zonyl BA-L을 이용하였다. 제조된 막을 이용하여 주사 전자 현미경법(SEM)과 접촉각 측정(Contact angle)을 하였고, 투과증발(Pervaporation)공정을 이용하여 물-에탄올 계의 분리실험을 통해 특성 평가를 하였다. 그 결과 SEM image를 통하여 SMM이 PVDF막 표면에 층을 형성하였음을 알 수 있었고, 접촉각은 기존의 PVDF 막 보다 SMM을 2 wt% 첨가하였을 때 8℃ 증가한 것으로 보아 소수성이 증가한 것을 알 수 있었다. 또한 물-에탄올 계에 대한 투과증발 실험은 다양한 조업온도별(50, 60, 70℃)로 수행하였으며, Zonyl의 함량이 PVDF 대비 1, 2 wt% 함유된 막을 사용하였으며 원액의 조성은 무게비로 물 10, 20, 50, 100%에 대하여 조사하였다. 물 : 에탄을 = 10 : 90 조성, 조업온도 50℃에서 선택도 287과 투과도 5.3 g/m 2 hr를 PVDF/2 wt% Zonyl BA-L 막이 보여주었다.

본 연구에서 배양액 내 첨가된 macromolecule이 돼지 체외수정란의 체외 발달율에 미치는 영향과 배양소적 내 첨가된 FBS가 후기배발달에 미치는 영향에 대하여 알아보았다. 이에 대한 결과를 요약 하면 다음과 같다. 1. NCSU-23을 기본 배양액으로 사용시 BSA (4mg/ml), FBS (10%), PVA (3 mg/ml)가 각각 첨가되었을 경우 배발달에 큰 차이를 보이지 않았다. 2. PZM을 기본 배양액으로 사용시 BSA (4mg/ml)가

the present study was carried out to develop a completely defined culture system and determine if high NaCl concentrations in defined (PVA added) or semi-defined (BSA added) medium is toxic to bovine embryos. Oocytes from slaughterhouse ovaries were matured and fertilized in vitro. After 30 h of insemination, only 2-cell stage embryos were selected and cultured for this experiment. The culture media used were as follows : TLP(114 mM of NaCl) + BSA (3 mg/ml), TLP + PVA (1 mg/ml), mTLP(96 mM of NaCl) + BSA, mTLP + PVA. Six to ten embryos were placed into a 301 drop of each medium and the embryos were examined at 10 day post-insemination without medium renewal. The experiment was replicated 4 times. All data were analyzed by chi-square. There were no significant differences among TLP-BSA, mTLP-BSA and mTLP-PVA in blastocyst development (21.6, 17.2 and 20.2%), respectively. Also, no differences were obtained in hatching rates (11.7, 9.9 and 12.2%), respecitively. However, there were significant differences between TLP-PVA (1.7% and 0.6%) and other group in blastocyst formation and hatching rates, respectively (p<0.01). Development of in vitro produced embryos cultured in BSA containing medium was not affected by high NaCl concentration, but in the completely defined medium, embryonic development was highly affected by NaCl. This study shows that reduced NaCl concentration in completely defined medium is beneficial for development of bovine pre-implantation embryos in vitro.