Sawada Toshiki, Serizawa Takeshi
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan.
Protein Pept Lett. 2018;25(1):64-67. doi: 10.2174/0929866525666171214104959.
Filamentous M13 phages have recently been utilized as components for developing novel functional soft materials in various fields such as sensor, device, and biomedical applications. Recently, we have developed liquid crystalline hydrogels composed of M13 phages and gold nanoparticles (GNPs) based on specific interactions between the components.
The main objective of this study was to clarify the self-healing capability of the hydrogels composed of M13 phages and GNPs.
M13 phages displaying tag peptides with a sequence of YPYDVPDYA (HA phages) were genetically constructed through general molecular biology. The mechanical strength of hydrogels composed of the HA phages and anti-HA peptide antibodies-immobilized GNPs (HA-GNPs) was measured by indentation tests. The rupture point of the hydrogels was visually observed. An aliquot of buffer solution was added into the rupture point of the hydrogels after the indentation test. After incubation for 2 days, self-healing of the rupture point was checked visually. The indentation test was also performed after self-healing. To clarify the assembled structures of the components in the hydrogels, transmission electron microscopy (TEM) observation was performed by transferring the hydrogel onto a TEM grid before and after healing.
The strength of the original hydrogel (before self-healing) required for rupture was approximately 55 mN. Self-healing of the rupture point was confirmed visually, and the hydrogels behaved as uniform hydrogels again during the vial inversion tests. As a result of the indentation test for the self-healed points of the hydrogels, the rupture force of approximately 45 mN was detected, indicating the self-healing capability of the hydrogels. TEM observation of the before and after self-healing exhibited the regularly assembled structures composed of the HA-GNPs, suggesting that the ruptured networks were recovered into regularly assembled network structures. Importantly, control of the concentration of the HA-GNPs resulted in suppression of decreasing the rupture forces during the repetitive self-healing processes.
Our results demonstrated the self-healing capability of structurally regular hybrid hydrogels composed of genetically engineered filamentous viruses displaying antigen peptides and antibody-immobilized GNPs. The results indicated that supramolecular hydrogels containing filamentous viruses would expand the applicability of virus-based soft materials.
丝状M13噬菌体最近已被用作开发新型功能软材料的组件，用于传感器、设备和生物医学应用等各个领域。最近，我们基于组件之间的特定相互作用，开发了由M13噬菌体和金纳米颗粒（GNP）组成的液晶水凝胶。
本研究的主要目的是阐明由M13噬菌体和GNP组成的水凝胶的自愈能力。
通过常规分子生物学方法构建了展示序列为YPYDVPDYA的标签肽的M13噬菌体（HA噬菌体）。通过压痕试验测量由HA噬菌体和固定有抗HA肽抗体的GNP（HA-GNP）组成的水凝胶的机械强度。目视观察水凝胶的破裂点。在压痕试验后，将等分的缓冲溶液加入水凝胶的破裂点。孵育2天后，目视检查破裂点的自愈情况。自愈后也进行了压痕试验。为了阐明水凝胶中组件的组装结构，在愈合前后将水凝胶转移到透射电子显微镜（TEM）网格上进行TEM观察。
原始水凝胶（自愈前）破裂所需的强度约为55 mN。目视确认了破裂点的自愈情况，并且在小瓶倒置试验期间水凝胶再次表现为均匀的水凝胶。对水凝胶自愈点进行压痕试验的结果显示，检测到约45 mN 的破裂力，表明水凝胶具有自愈能力。自愈前后的TEM观察显示由HA-GNP组成的规则组装结构，表明破裂的网络恢复为规则组装的网络结构。重要的是，控制HA-GNP的浓度可抑制重复自愈过程中破裂力的降低。
我们的结果证明了由展示抗原肽的基因工程丝状病毒和固定有抗体的GNP组成的结构规则的混合水凝胶具有自愈能力。结果表明，含有丝状病毒的超分子水凝胶将扩大基于病毒的软材料的适用性。
