Effects of phosphate, Tris, HEPES, or MOPS buffers on the formation of silk fibroin sponges
Effects of phosphate, Tris, HEPES, or MOPS buffers on the formation of silk fibroin sponges
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磷酸盐、Tris、HEPES 或 MOPS 缓冲液对丝素蛋白海绵形成的影响
DOI：
10.11417/silk.26.21
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Kambe Y，Tamada Y，Kameda T
中科院分区：
文献类型：
--
作者：
Cui Yang;Takamatsu Taiki;Shimizu Koichi;Miyake Takeo;Kambe Y，Tamada Y，Kameda T
我们研究了在含有1%（v/v）二甲亚砜的丝素蛋白（SF）水溶液中加入缓冲液（pH7.4，25 ℃）对使用溶液的单次冷冻/解冻获得的SF海绵状结构的形成的影响。磷酸钠缓冲液（Na 2 HPO 4和NaH 2 PO 4的混合物; SP）的加入使SF海绵状结构更精细和更硬，显示出最小孔径和最大拉伸模量在80 mM。相反，三（羟甲基）氨基甲烷，4-（2-羟乙基）-1-哌嗪乙磺酸和3-（N-吗啉代）丙磺酸缓冲液抑制SF海绵的形成。我们推测缓冲液中离子的盐进/盐出效应影响SF海绵的形成; SP中的HPO 4 2-和H2 PO 4-可能强烈水合，使SF蛋白通过疏水相互作用组装。因为据报道SP的缓冲作用不受温度的影响，所以在冻融过程中SF溶液的pH预期保持在7.4左右以形成SF海绵。SP缓冲液的SF溶液的添加可能会保持SF蛋白的活性与pH敏感的生物活性蛋白修饰，即使在制造成海绵状结构。此外，所得SF海绵可显示出高的机械性能。由于转基因家蚕技术的最新进展，使重组SF蛋白融合到生物活性蛋白的生产，在这项研究中的发现是适用于生物活性SF海绵的形成，用于组织工程的支架。（*：信件应寄给谁，电子邮件：kamedat@ affrc。走了jp）
We investigated the effects of the addition of buffers (pH 7.4 at 25 C) to a silk fibroin (SF) aqueous solution containing 1%(v/v) dimethylsulfoxide on the formation of a SF spongy structure obtained using a single freeze/thawing of the solution. The addition of a sodium phosphate (a mixture of Na2HPO4 and NaH2PO4; SP) buffer made the SF spongy structure finer and harder dosedependently, showing the minimum pore size and maximum tensile modulus at 80 mM. In contrast, tris (hydroxymethyl) aminomethane, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, and 3-(N-morpholino) propanesulfonic acid buffers inhibited the SF sponge formation. We infer that the salting in/out effect of ions in buffers affected the SF sponge formation; HPO4 2-and H2PO4-from SP might be strongly hydrated to make SF proteins assemble by hydrophobic interaction. Because the buffering effect of SP is reportedly insulated from the influence of temperature, the pH of the SF solution was expected to be maintained as around 7.4 during the freeze–thawing process to form the SF sponge. The addition of the SP buffer to the SF solution was likely to maintain the activity of SF proteins modified with pH-sensitive bioactive proteins, even after fabrication into the spongy structure. Furthermore, the resulting SF sponge might show high mechanical properties. Because recent advances in transgenic silkworm technology have enabled the production of recombinant SF protein fused to bioactive proteins, the findings in this study are applicable in the formation of bioactive SF sponges to be used as scaffolds for tissue engineering.(*: To whom correspondence should be addressed, E mail: kamedat@ affrc. go. jp)