Direct Observation of the Interplay of Catechol Binding and Polymer Hydrophobicity in a Mussel-Inspired Elastomeric Adhesive.
Direct Observation of the Interplay of Catechol Binding and Polymer Hydrophobicity in a Mussel-Inspired Elastomeric Adhesive.
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DOI：
10.1021/acscentsci.8b00526
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发表时间：
2018-10-24
影响因子：
18.2
通讯作者：
Dhinojwala A
中科院分区：
文献类型：
--
作者：
Kaur S;Narayanan A;Dalvi S;Liu Q;Joy A;Dhinojwala A
海洋生物如贻贝已经通过在粘附蛋白中掺入后降解修饰的氨基酸如1 - 3，4-二羟基苯丙氨酸（DOPA）来应对水下粘附的挑战。在这里，我们设计了一种含邻苯二酚的弹性体粘合剂，以确定邻苯二酚在干和湿条件下的界面粘合中的作用。为了使儿茶酚对整体粘合的粘合贡献解耦，弹性体被设计为通过香豆素的[2 + 2]光环加成而交联。具有邻苯二酚部分的弹性体显示出比邻苯二酚保护的弹性体更高的粘合强度。接触界面探测使用界面敏感的和频发生光谱，探讨邻苯二酚是否可以取代水和键合的亲水性表面的问题。光谱测量显示邻苯二酚和受保护的邻苯二酚弹性体与蓝宝石衬底的最大结合能为7.0 ± 0.1 kJ/（表面O-H摩尔），其相当于0.10 J/m2。在含邻苯二酚的弹性体的宏观粘附力测量中观察到的较高的干和湿粘附力源自邻苯二酚二羟基基团与表面的多个氢键。此外，我们的研究结果表明，邻苯二酚本身并不消除封闭的间隙水。在这些弹性体中，疏水基团有助于部分去除间隙水。邻苯二酚结合和疏水性之间的协同作用，使贻贝启发的软粘合剂弹性体坚持水下的观察提供了一个框架，用于设计材料的组织粘附和皮肤可穿戴电子产品中的应用。结合粘附力和界面敏感的光谱测量，我们显示了聚合物的疏水性和儿茶酚结合的协同作用，在水下附着的贻贝启发聚合物。
Marine organisms such as mussels have mastered the challenges in underwater adhesion by incorporating post-translationally modified amino acids like l-3,4-dihydroxyphenylalanine (DOPA) in adhesive proteins. Here we designed a catechol containing elastomer adhesive to identify the role of catechol in interfacial adhesion in both dry and wet conditions. To decouple the adhesive contribution of catechol to the overall adhesion, the elastomer was designed to be cross-linked through [2 + 2] photo-cycloaddition of coumarin. The elastomer with catechol moieties displayed a higher adhesion strength than the catechol-protected elastomer. The contact interface was probed using interface-sensitive sum frequency generation spectroscopy to explore the question of whether catechol can displace water and bond with hydrophilic surfaces. The spectroscopy measurements reveal that the maximum binding energy of the catechol and protected-catechol elastomers to sapphire substrate is 7.0 ± 0.1 kJ/(mole of surface O–H), which is equivalent to 0.10 J/m2. The higher dry and wet adhesion observed in the macroscopic adhesion measurements for the catechol containing elastomer originates from multiple hydrogen bonds of the catechol dihydroxy groups to the surface. In addition, our results show that catechol by itself does not remove the confined interstitial water. In these elastomers, it is the hydrophobic groups that help in partially removing interstitial water. The observation of the synergy between catechol binding and hydrophobicity in enabling the mussel-inspired soft adhesive elastomer to stick underwater provides a framework for designing materials for applications in tissue adhesion and moist-skin wearable electronics. Combining adhesion and interface-sensitive spectroscopy measurements, we show the synergistic action of polymer hydrophobicity and catechol binding in underwater adhesion of mussel-inspired polymers.
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影响因子：
6.2
作者：
Clancy, Sean K.;Sodano, Antonio;Ahn, B. Kollbe
通讯作者：
Ahn, B. Kollbe
影响因子：
2.9
作者：
Danner EW;Kan Y;Hammer MU;Israelachvili JN;Waite JH
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Waite JH
影响因子：
5.5
作者：
Govindarajan, Sudhanva R.;Xu, Ying;Joy, Abraham
通讯作者：
Joy, Abraham
影响因子：
3.6
作者：
GNANAGURU, K;RAMASUBBU, N;RAMAMURTHY, V
通讯作者：
RAMAMURTHY, V
影响因子：
3.9
作者：
CHAUDHURY, MK;WHITESIDES, GM
通讯作者：
WHITESIDES, GM