Antibody-Mimetic Peptoid Nanosheets for Molecular Recognition

The ability of antibodies to bind a wide variety of analytes with high specificity and high affinity make them ideal candidates as molecular recognition elements for chemical and biological sensors. However, their widespread use in sensing devices has been hampered by their poor stability and high production cost. Here we report the design and synthesis of a new class of antibody-mimetic materials based on functionalized peptoid nanosheets. A high density of conformationally constrained peptide and peptoid loops are displayed on the surface of free-floating nanosheets to generate an extended, multivalent two-dimensional material that is chemically and biologically stable. The nanosheet serves as a robust, high-surface area scaffold upon which to display a wide variety of functional loop sequences. The functionalized nanosheets were characterized by atomic force microscopy, X-ray diffraction, and X-ray reflectivity measurements, and were shown to serve as substrates for enzymes (protease and casein kinase II), as well as templates for the growth of defined inorganic materials (gold metal).

抗体可凭借高特异性与高亲和力结合多种分析物，这一特性使其成为化学生物传感器领域中分子识别元件（molecular recognition elements）的理想候选材料。然而，其在传感设备中的大规模应用却因稳定性欠佳与制备成本高昂而受到限制。本文报道了一类基于功能化类肽纳米片（functionalized peptoid nanosheets）的新型抗体模拟材料的设计与合成方案。该类材料通过在游离悬浮的纳米片表面展示高密度的构象受限肽与类肽环，可形成兼具化学与生物稳定性的扩展型多价二维材料。该纳米片可作为一种高比表面积的坚固支架，用于展示多种功能环序列。研究人员通过原子力显微镜（atomic force microscopy）、X射线衍射（X-ray diffraction）以及X射线反射率测试对该功能化纳米片进行了表征，结果证实其可作为蛋白酶与酪蛋白激酶II等酶的底物，同时也可作为定向生长无机材料（金属金）的模板。