Designer self-assembling peptide materials

Understanding of macromolecular materials at the molecular level is becoming increasingly important for a new generation of nanomaterials for nanobiotechnology and other disciplines, namely, the design, synthesis, and fabrication of nanodevices at the molecular scale from bottom up. Basic engineering principles for microfabrication can be learned through fully grasping the molecular self-assembly and programmed assembly phenomena. Self- and programmed-assembly phenomena are ubiquitous in nature. Two key elements in molecular macrobiological material productions are chemical complementarity and structural compatibility, both of which require weak and non-covalent interactions that bring building blocks together during self-assembly. Significant advances have been made during the 1990s at the interface of materials chemistry and biology. They include the design of helical ribbons, peptide nanofiber scaffolds for three-dimensional cell cultures and tissue engineering, peptide surfactants for solubilizing and stabilizing diverse types of membrane proteins and their complexes, and molecular ink peptides for arbitrary printing and coating surfaces as well as coiled-coil helical peptides for multi-length scale fractal structures. These designer self-assembling peptides have far reaching implications in a broad spectrum of applications in biology, medicine, nanobiotechnology, and nanobiomedical technology, some of which are beyond our current imaginations. [image: see text]     

Designer nanomaterials using chiral self-assembling peptide systems and their emerging benefit for society

Chirality is absolutely central in chemistry and biology. The recent findings of chiral self-assembling peptides' remarkable chemical complementarity and structural compatibility make it one of the most inspired designer materials and structures in nanobiotechnology. The emerging field of designer chemistry and biology further explores biological and medical applications of these simple D,L- amino acids through producing marvellous nanostructures under physiological conditions. These self-assembled structures include well-ordered nanofibers, nanotubes and nanovesicles. These structures have been used for 3-dimensional tissue cultures of primary cells and stem cells, sustained release of small molecules, growth factors and monoclonal antibodies, accelerated wound-healing in reparative and regenerative medicine as well as tissue engineering. Recent advances in molecular designs have also led to the development of 3D fine-tuned bioactive tissue culture scaffolds. They are also used to stabilize membrane proteins including difficult G-protein coupled receptors for designing nanobiodevices. One of the self-assembling peptides has been used in human clinical trials for accelerated wound-healings. It is our hope that these peptide materials will open doors for more and diverse clinical uses. The field of chiral self-assembling peptide nanobiotechnology is growing in a number of directions that has led to many surprises in areas of novel materials, synthetic biology, clinical medicine and beyond.     

Miscellaneous applications of ferrocene‐based peptides/amides

This article provides a critical review of the different applications of ferrocene‐based peptides/amides in biological as well as in non‐biological systems. Ferrocene‐based peptides/amides find many applications in different fields such as materials science, medicine, organic synthesis, bio‐organometallic and biological chemistry, asymmetric catalysis, nonlinear optics, in polymer science as redox active polymers and dendrimers, in molecular recognition as biosensors and in electrochemistry). Extensive research is being done on ferrocene‐based peptides/amides but we will highlight the various applications of ferrocene‐based peptides/amides for the period 2006–2010. The main factors that govern the potential biological and non‐biological applications are an electroactive core, a conjugated linker that can act as a chromophore and lower the oxidation potential of the ferrocene part, an amino acid or peptide derivative that can interact with other molecules via hydrogen bonding or any secondary bonding, and symmetric and asymmetric substitution on the ferrocene moiety. Copyright © 2011 John Wiley & Sons, Ltd.     

界面上蜂窝状多孔薄膜的构建、性质和应用

综述了以Breath Figure(呼吸图案)法制备聚合物及纳米颗粒蜂窝状多孔结构的研究现状.当潮湿的气流吹到聚合物或纳米颗粒的有机溶液表面时,溶剂蒸发导致水微滴在液体表面冷凝重排成六角阵列结构.溶剂和水微滴蒸发完毕后,聚合物或纳米颗粒在基底上形成具有六角阵列的蜂窝状多孔结构.该技术是自组装领域的一大进展,在生物技术、组织工程、微图像技术、高端分离技术、光催化及医药等领域有望获得重要应用.本文系统阐述了规整蜂窝状孔结构材料的构建方法、构建材料、形成机理以及影响因素(包括湿度、浓度、气流方向和速度、溶剂、基底曲率等),评述了蜂窝状多孔薄膜的性质和应用,并对其在化学和材料科学领域的应用前景作了展望.     

分析化学进展

随着纳米材料、膜材料、有机功能材料、离子液体,以及光电技术、计算机科学的发展,分析化学在色谱、质谱、光谱、电分析等各分支领域都取得了重要进展。当然,分析化学的发展也有力地推动了我国的生命科学、材料科学、医学、生态与环境化学、矿产、食品安全等许多领域和学科的发展和进步。近年来,我国分析化学学科在与生命科学的学科交叉研究十分活跃,主要集中在蛋白质组学、代谢组学、金属组学中的新分析方法和新分析技术,例如纳米生物技术、生物传感器、微流控系统与芯片技术等,取得了一大批重要的研究成果。此外,针对食品安全、生态环境监测、药品检测、流行疾病应急响应等人们关注的热点开发了许多新的实用技术与方法;在大中型分析仪器的研发方面也取得喜人的进步。共引用97篇参考文献。     

Peptides as New Smart Bionanomaterials: Molecular‐Recognition and Self‐Assembly Capabilities

Biomolecules express exquisite properties that are required for molecular recognition and self‐assembly on the nanoscale. These smart capabilities have developed through evolution and such biomolecules operate based on smart functions in natural systems. Recently, these remarkable smart capabilities have been utilized in not only biologically related fields, but also in materials science and engineering. A peptide‐screening technology that uses phage‐display systems has been developed based on this natural smart evolution for the generation of new functional peptide bionanomaterials. We focused on peptides that specifically bound to synthetic polymers. These polymer‐binding peptides were screened by using a phage‐display peptide library to recognize nanostructures that were derived from polymeric structural features and were utilized for possible applications as new bionanomaterials. We also focused on self‐assembling peptides with β‐sheet structures that formed nanoscale, fibrous structures for applications in new bottom‐up nanomaterials. Moreover, nanofiber‐binding peptides were also screened to introduce the desired functionalities into nanofibers without the need for additional molecular design. Our approach to construct new bionanomaterials that employ peptides will open up excellent opportunities for the next generation of materials science and technology.     

Construction and activity of a synthetic basement membrane with active laminin peptides and polysaccharides

Cell-adhesive peptides derived from extracellular matrix (ECM) proteins are potential candidates for incorporating cell-binding activities into materials for tissue engineering. We have identified a number of cell adhesive peptides from laminins, which are major components of basement membrane ECM. Our goal is the development of synthetic basement membranes using the peptides on scaffolds. We review peptide–polysaccharide complexes, which were prepared by conjugation of the peptides to chitosan and alginate, and the biological activities of the resulting matrices. The peptide–polysaccharide matrices can also be used as a biomaterial for cell transplantation. These studies suggest that the peptide–polysaccharide complexes have the potential to mimic the multifunctional basement membrane and may be useful for tissue engineering.     

液晶的超分子系统及生物膜模拟

本文评述了自组织产生功能的原理及溶致性液晶对生命科学的重要意义。这些是生命发展及细胞产生功能的先决条件。在高分子材料科学中, 通过自组织作用产生功能的原理导致了新的液晶材料。分子的自组织作用形成超分子体系从而产生相应的功能。从高分子材料科学的观点出发, 我们尝试将这两个领域结合在一起, 并希望能促进它们之间的相互作用和联合处理。同时评述了液晶的超分子体系、生物膜模型, 高分子脂质体及其在化学与生物医学方面的应用。如果双分子层的组装概念能更一般地延伸到有机介质, 那么一种全新的化学分支将会产生。     

多孔晶体材料的分子工程学研究

功能无机晶体材料的定向设计与合成是化学及材料科学领域中一项重要的前沿课题。本文介绍了近十几年来我们在多孔晶体材料,主要包括分子筛和金属有机骨架晶体材料的分子工程学研究方面所取得的一些进展。其中包括提出了定向设计具有特殊孔道结构和特殊计量比分子筛多孔骨架结构的计算机方法;在国际上率先建立了分子筛多孔晶体材料合成与结构数据...     

“What Doesn’t Kill You Makes You Stronger”: Future Applications of Amyloid Aggregates in Biomedicine

Amyloid proteins are linked to the pathogenesis of several diseases including Alzheimer’s disease, but at the same time a range of functional amyloids are physiologically important in humans. Although the disease pathogenies have been associated with protein aggregation, the mechanisms and factors that lead to protein aggregation are not completely understood. Paradoxically, unique characteristics of amyloids provide new opportunities for engineering innovative materials with biomedical applications. In this review, we discuss not only outstanding advances in biomedical applications of amyloid peptides, but also the mechanism of amyloid aggregation, factors affecting the process, and core sequences driving the aggregation. We aim with this review to provide a useful manual for those who engineer amyloids for innovative medicine solutions.     

High-tech applications of self-assembling supramolecular nanostructured gel-phase materials: from regenerative medicine to electronic devices

It is likely that nanofabrication will underpin many technologies in the 21st century. Synthetic chemistry is a powerful approach to generate molecular structures that are capable of assembling into functional nanoscale architectures. There has been intense interest in self-assembling low-molecular-weight gelators, which has led to a general understanding of gelation based on the self-assembly of molecular-scale building blocks in terms of non-covalent interactions and packing parameters. The gelator molecules generate hierarchical, supramolecular structures that are macroscopically expressed in gel formation. Molecular modification can therefore control nanoscale assembly, a process that ultimately endows specific material function. The combination of supramolecular chemistry, materials science, and biomedicine allows application-based materials to be developed. Regenerative medicine and tissue engineering using molecular gels as nanostructured scaffolds for the regrowth of nerve cells has been demonstrated in vivo, and the prospect of using self-assembled fibers as one-dimensional conductors in gel materials has captured much interest in the field of nanoelectronics.     

Peptide Nanotubes

The self‐assembly of different classes of peptide, including cyclic peptides, amyloid peptides and surfactant‐like peptides into nanotube structures is reviewed. The modes of self‐assembly are discussed. Additionally, applications in bionanotechnology and synthetic materials science are summarized.     

3'-Ferrocene-labeled oligonucleotide chains end-tethered to gold electrode surfaces: novel model systems for exploring flexibility of short DNA using cyclic voltammetry

The flexibility of DNA is of central importance in biology, medicine, materials science, and mechanical engineering. In this study, we report an unprecedented electrochemical approach for investigating the flexibility of a short (typically 20-base), surface end-tethered single-stranded synthetic DNA oligonucleotide and of its postformed DNA duplex, taking as an example the homopolymer (dT)20 sequence in the regime of very high ionic strength ( approximately 1 M).     

Short peptides enhance single cell adhesion and viability on microarrays

Single cell patterning holds important implications for biology, biochemistry, biotechnology, medicine, and bioinformatics. The challenge for single cell patterning is to produce small islands hosting only single cells and retaining their viability for a prolonged period of time. This study demonstrated a surface engineering approach that uses a covalently bound short peptide as a mediator to pattern cells with improved single cell adhesion and prolonged cellular viability on gold patterned SiO2 substrates. The underlying hypothesis is that cell adhesion is regulated by the type, availability, and stability of effective cell adhesion peptides, and thus covalently bound short peptides would promote cell spreading and, thus, single cell adhesion and viability. The effectiveness of this approach and the underlying mechanism for the increased probability of single cell adhesion and prolonged cell viability by short peptides were studied by comparing cellular behavior of human umbilical cord vein endothelial cells on three model surfaces whose gold electrodes were immobilized with fibronectin, physically adsorbed Arg-Glu-Asp-Val-Tyr, and covalently bound Lys-Arg-Glu-Asp-Val-Tyr, respectively. The surface chemistry and binding properties were characterized by reflectance Fourier transform infrared spectroscopy. Both short peptides were superior to fibronectin in producing adhesion of only single cells, whereas the covalently bound peptide also reduced apoptosis and necrosis of adhered cells. Controlling cell spreading by peptide binding domains to regulate apoptosis and viability represents a fundamental mechanism in cell-materials interaction and provides an effective strategy in engineering arrays of single cells.     

Ordered mesoporous materials in the context of drug delivery systems and bone tissue engineering

Chemistry, materials science and medicine are research areas that converge in the field of drug delivery systems and tissue engineering. This paper tries to introduce an example of such an interaction, aimed at solving health issues within the world of biomaterials. Ordered mesoporous materials can be loaded with different organic molecules that would be released afterwards, in a controlled fashion, inside a living body. These materials can also react with the body fluids giving rise to carbonated nanoapatite particles as the products of such a chemical interaction; these particles, equivalent to biological apatites, enable the regeneration of bone tissue.     

Utilisation of plant viruses in bionanotechnology

Bionanoscience/technology sits at the interface of chemistry, biology, physics, materials science, engineering and medicine and involves the exploitation of biomaterials, devices or methodologies on the nanoscale. One sub-field of bionanoscience/technology is concerned with the exploitation of biomaterials in the fabrication of new nano-materials and/or -devices. In this Perspective we describe examples of how plant viruses, focusing particularly on cowpea mosaic virus, a naturally occurring pre-formed sphere-like nanoparticle, are being used as templates and/or building blocks in bionanoscience and indicate their potential for future application.     

Tailoring the volatility and stability of oligopeptides

Amino acids are essential building blocks of life, and fluorinated derivatives have gained interest in chemistry and medicine. Modern mass spectrometry has enabled the study of oligo‐ and polypeptides as isolated entities in the gas phase, but predominantly as singly or even multiply charged species. While laser desorption of neutral peptides into adiabatically expanding supersonic noble gas jets is possible, UV–VIS spectroscopy, electric or magnetic deflectometry as well as quantum interferometry would profit from the possibility to prepare thermally slow molecular beams. This has typically been precluded by the fragility of the peptide bond and the fact that a peptide would rather ‘fry’, i.e. denature and fragment than ‘fly’. Here, we explore how tailored perfluoroalkyl functionalization can reduce the intermolecular binding and thus increase the volatility of peptides and compare it to previously explored methylation, acylation and amidation of peptides. We show that this strategy is essential and enables the formation of thermal beams of intact neutral tripeptides, whereas only fragments were observed for an extensively fluoroalkyl‐decorated nonapeptide. © 2017 The Authors. Journal of Mass Spectrometry Published by John Wiley & Sons Ltd.     

αvβ3‐ or α5β1‐Integrin‐Selective Peptidomimetics for Surface Coating

Engineering biomaterials with integrin‐binding activity is a very powerful approach to promote cell adhesion, modulate cell behavior, and induce specific biological responses at the surface level. The aim of this Review is to illustrate the evolution of surface‐coating molecules in this field: from peptides and proteins with relatively low integrin‐binding activity and receptor selectivity to highly active and selective peptidomimetic ligands. In particular, we will bring into focus the difficult challenge of achieving selectivity between the two closely related integrin subtypes αvβ3 and α5β1. The functionalization of surfaces with such peptidomimetics opens the way for a new generation of highly specific cell‐instructive surfaces to dissect the biological role of integrin subtypes and for application in tissue engineering and regenerative medicine.     

Amyloid Aggregates Arise from Amino Acid Condensations under Prebiotic Conditions

Current theories on the origin of life reveal significant gaps in our understanding of the mechanisms that allowed simple chemical precursors to coalesce into the complex polymers that are needed to sustain life. The volcanic gas carbonyl sulfide (COS) is known to catalyze the condensation of amino acids under aqueous conditions, but the reported di‐, tri‐, and tetra‐peptides are too short to support a regular tertiary structure. Here, we demonstrate that alanine and valine, two of the proteinogenic amino acids believed to have been among the most abundant on a prebiotic earth, can polymerize into peptides and subsequently assemble into ordered amyloid fibers comprising a cross‐β‐sheet quaternary structure following COS‐activated continuous polymerization of as little as 1 mm amino acid. Furthermore, this spontaneous assembly is not limited to pure amino acids, since mixtures of glycine, alanine, aspartate, and valine yield similar structures.     

组合化学在功能材料合成方面的应用

组合化学方法是当今材料科学和化学领域的研究热点。组合化学方法首先在新药的合成领域得到应用, 很快就以其合成周期短、合成的样品数量大、节约经费等诸多优点而拓展到功能材料的合成等其它领域。组合化学的方法有许多种, 按照反应相的不同可以分为液相中的组合合成法和固相中的组合合成法, 固相组合合成又可以根据所选用的掩模方式的不同而分为二分阴影掩模法、四分阴影掩模法、可移动百叶窗式掩模法等几种, 可以根据材料合成的实际需求加以选择。