Peptide Nanomaterials Designed from Natural Supramolecular Systems

Natural supramolecular assemblies exhibit unique structural and functional properties that have been optimized over the course of evolution. Inspired by these natural systems, various bio-nanomaterials have been developed using peptides, proteins, and nucleic acids as components. Peptides are attractive building blocks because they enable the important domains of natural protein assemblies to be isolated and optimized while retaining the original structures and functions. Furthermore, the peptide subunits can be conjugated with exogenous molecules such as peptides, proteins, nucleic acids, and metal nanoparticles to generate advanced functions. In this personal account, we summarize recent progress in the construction of peptide-based nanomaterial designed from natural supramolecular systems, including (1) artificial viral capsids, (2) self-assembled nanofibers, and (3) protein-binding motifs. The peptides inspired by nature should provide new design principles for bio-nanomaterials

DNA Walkers: Emerging Analytical Applications, Biomolecular-Nanomaterial Probes and Biomolecule Sensors

DNA walkers are a unique class of dynamic DNA devices that move nucleic acid walkers processively along designated one-, two-, or three-dimensional tracks. Because of the unique mechanical motion, dynamic interaction, and capabilities for signal amplification, programmable signal transduction, high directionality, and predictable analytical performance on the basis of Watson-Crick base paring rules, this class of dynamic DNA nanodevice has gained great attention from the analytical community in the recent years. This includes bioanalytical applications that range from nucleic acid sensing, to protein detection and to cellular imaging and analysis. The research described herein focuses on improving the understanding of biophysical processes involved in the design and operation of DNA walkers. Specifically, we developed a series of stochastic DNA walkers capable of probing dynamic interactions occurring at the biomolecule-nanoparticle (bio-nano) interface. By monitoring dynamics of DNA walkers on spherical nucleic acid (SNA) tracks, we systematically investigated effects of varying interfacial factors, including intramolecular interactions, orientation, cooperativity, steric effect, multivalence, and binding hindrance on enzymatic activities at the bio-nano interface. Leveraging the newly gained knowledge at the interface, we also fabricated ultrasensitive biosensors for amplified detection of nucleic acids and antibodies. Our study revealed critical roles of interfacial factors to enzyme activities and performance of enzyme-driven nanodevices. We also demonstrate that improvement in understanding bio-nano interfaces will facilitate the design and operation of biosensors and inspire new sensing mechanisms

DNA-Based Applications in Nanobiotechnology

Biological molecules such as deoxyribonucleic acid (DNA) have shown great potential in fabrication and construction of nanostructures and devices. The very properties that make DNA so effective as genetic material also make it a very suitable molecule for programmed self-assembly. The use of DNA to assemble metals or semiconducting particles has been extended to construct metallic nanowires and functionalized nanotubes. This paper highlights some important aspects of conjugating the unique physical properties of dots or wires with the remarkable recognition capabilities of DNA which could lead to miniaturizing biological electronics and optical devices, including biosensors and probes. Attempts to use DNA-based nanocarriers for gene delivery are discussed. In addition, the ecological advantages and risks of nanotechnology including DNA-based nanobiotechnology are evaluated

Smart hybrid nanomaterials for biomimetic membranes

This thesis focuses on the preparation of nanomaterials made of proteins and polymers. Even though the technology has advanced in the last decades to design new devices at the atomic scale, researchers are still inspired by what Nature has produced and optimized for millions of years. Following this concept, this work uses proteins forming water-filled channels, called porins, which regulate the flow of ions and biomolecules in cellular life. Two proteins were studied: Omp2a and VDAC36. The first part of the dissertation is the thermomechanical properties study of the latest hybrid membrane developed by the IMEM group: an thin nanoperforated poly(lactic acid) (PLA) film with the Omp2a porin immobilized onto the surface . For this purpose, a new equipment based on the microcantilever technology was used. The SCAnning LAser analyzer (SCALA) characterizes the coated cantilevers which allows the following of the cantilever bending induced by the compression/expansion of the sample coating (i.e. proteins or polymers). In this study, the intermolecular reorganization of Omp2a aggregates was evidenced as well as the protein secondary structure stability against temperature. The same method was employed to study the impact of nanofeatures (perforations and drugs domains) on films of PLA. They affected the glass transition and the cold crystallization temperatures. The changes were dependent on the size and abundance of the nanofeatures, which can modulate the properties of future materials. Moreover, this work established a protocol for the study of biomolecules and polymers attached to microcantilevers, allowing an accurate study of the thermomechanical properties using very low amounts of sample. The second part of the thesis is the development of new hybrid nanomaterials composed of VDAC36, PLA and poly(3,4-ethylenedioxythiophene) (PEDOT). An efficient protocol was established for the production of VDAC36 and its subsequent refolding was achieved. The beta-barrel nature of the protein was revealed and its tendency to form oligomers was demonstrated. Finally, the size of the protein inner channel could be determined. The VDAC36 was added to the polymer material made of three alternating layers of PLA and PEDOT. The electrical properties of the material were modified by the addition of the protein: the overall resistance was reduced and the supercapacitive behaviour was enhanced. The description of the electrical equivalent circuit also revealed that the protein induced the diffusion of ions. To improve the material, the number of layers was increased and the conducting polymer was modified by incorporating a monomer bearing a dodecyl chain. The modifications were proved useful as the protein content and the electrical properties increased. Finally, the new hybrid material could provide an adaptive electrical response according to the concentration of biomolecules.Esta tesis se centra en la preparación de nanomateriales basados en proteínas y polímeros. A pesar de los avances realizados en las últimas décadas en el diseño de nuevos dispositivos a escala nanométrica, los investigadores aún se inspiran en lo que la Naturaleza ha producido y ha optimizado durante millones de años. A partir de esta premisa, en este trabajo se han usado proteínas, que constituyen canales de agua y cuya función es regular el paso de iones y biomoléculas en organismos celulares. Las proteínas involucradas son Omp2a y VDAC36. La primera parte de esta disertación se centra en el estudio de las propiedades termo-mecánicas de los componentes una novedosa membrana híbrida desarrollada per el grupo IMEM: una película ultra-delgada de ácido poli(láctico) (PLA) nano-perforada y funcionalizada en la superficie con moléculas de Omp2a. Para su caracterización se usó un nuevo equipo basado en la tecnología de micro-palancas. Un analizador laser de barrido (SCALA, el acrónimo de dicho aparato en inglés) permite caracterizar palancas recubiertas de muestra polimérica mediante la reflexión de un rayo de luz láser sobre la superficie del soporte revestido. Mediante su acoplado a una cámara termo-controlada, SCALA permite seguir la deformación del soporte inducida per la compresión/expansión de la muestra en forma de recubrimiento (ya sean polímeros como proteínas). Mediante esta técnica se evidenció la reorganización intermolecular en agregados de la proteína Omp2a, así como la alta estabilidad de su estructura secundaria en frente de la temperatura. El mismo método fue usado para estudiar el impacto de las nano-características sobre las películas de PLA. Nano-poros, nano-perforaciones y nano-dominios fueron añadidos a los films de PLA. Dichas modificaciones afectan tanto a su transición vítrea como a la cristalización en frío de dichas películas. Los cambios observados dependen del tamaño y la abundancia de las nano-modificaciones, lo cual va a permitir modular las propiedades de futuros nano-materiales. Más aún, este trabajo ha establecido las bases para un protocolo general de uso de micro-palancas para estudiar proteínas y polímeros unidos a ellas, permitiendo la caracterización de sus propiedades termo-mecánicas usando cantidades ínfimas de material. Se pudo establecer un protocolo eficiente para la producción de VDAC36 i su subsecuente re-naturalización por medio de una combinación de detergentes y alcoholes. Per medio de experimentos de dicroísmo circular se puso de manifiesto su naturaleza de barril beta y se mostró su tendencia a formar oligómeros mediante entrecruzamientos químicos. El tamaño del poro se pudo determinar mediante ensayos de hinchado. A continuación, VDAC36 se incorporó al material polimérico constituido por tres capas de polímero, alternando PLA y PEDOT. Las propiedades eléctricas de este material quedaron visiblemente modificadas por la adición de la proteína sobre los films de polímero: se redujo su resistancia mientras que su comportamiento como supercondensador, consecuencia la presencia de PEDOT, aumentó. La descripción del circuito eléctrico equivalente reveló a su vez que la proteína inducía la difusión de iones. Para mejorar la retención de proteínas y la integridad mecánica del material, las capas de polímero de la membrana se aumentaron hasta cinco. A su vez, el monómero de EDOT se modificó para incorporar una cadena de dodecilo y poder así imitar una membrana celular. Estas últimas modificaciones se mostraron de gran utilidad puesto que el contenido en proteína aumentó y los cambios eléctricos se hicieron más pronunciados. Finalmente, este nuevo material híbrido fue capaz de proporcionar una respuesta eléctrica adaptativa como respuesta a cambios en la concentración de biomoléculas.Postprint (published version

Recent progress in piezotronic sensors based on one-dimensional zinc oxide nanostructures and its regularly ordered arrays: from design to application

Piezotronic sensors and self-powered gadgets are highly sought-after for flexible, wearable, and intelligent electronics for their applications in cutting-edge healthcare and human-machine interfaces. With the advantages of a well-known piezoelectric effect, excellent mechanical properties, and emerging nanotechnology applications, one-dimensional (1D) ZnO nanostructures organized in the form of a regular array have been regarded as one of the most promising inorganic active materials for piezotronics. This report intends to review the recent developments of 1D ZnO nanostructure arrays for multifunctional piezotronic sensors. Prior to discussing rational design and fabrication approaches for piezotronic devices in precisely controlled dimensions, well-established synthesis methods for high-quality and well-controlled 1D ZnO nanostructures are addressed. The challenges associated with the well-aligned, site-specific synthesis of 1D ZnO nanostructures, development trends of piezotronic devices, advantages of an ordered array of 1D ZnO in device performances, exploring new sensing mechanisms, incorporating new functionalities by constructing heterostructures, the development of novel flexible device integration technology, the deployment of novel synergistic strategies in piezotronic device performances, and potential multifunctional applications are covered. A brief evaluation of the end products, such as small-scale miniaturized unconventional power sources in sensors, high-resolution image sensors, and personalized healthcare medical devices, is also included. The paper is summarized towards the conclusion by outlining the present difficulties and promising future directions. This study will provide guidance for future research directions in 1D ZnO nanostructure-based piezotronics, which will hasten the development of multifunctional devices, sensors, chips for human-machine interfaces, displays, and self-powered systems

Roadmap on Biological Pathways for Electronic Nanofabrication and Materials

Conventional microchip fabrication is energy and resource intensive. Thus, the discovery of new manufacturing approaches that reduce these expenditures would be highly beneficial to the semiconductor industry. In comparison, living systems construct complex nanometer-scale structures with high yields and low energy utilization. Combining the capabilities of living systems with synthetic DNA-/protein-based self-assembly may offer intriguing potential for revolutionizing the synthesis of complex sub-10 nm information processing architectures. The successful discovery of new biologically based paradigms would not only help extend the current semiconductor technology roadmap, but also offer additional potential growth areas in biology, medicine, agriculture and sustainability for the semiconductor industry. This article summarizes discussions surrounding key emerging technologies explored at the Workshop on Biological Pathways for Electronic Nanofabrication and Materials that was held on 16–17 November 2016 at the IBM Almaden Research Center in San Jose, CA

Application of Nanotechnology for Sensitive Detection of Low-Abundance Single-Nucleotide Variations in Genomic DNA: A Review

Single-nucleotide polymorphisms (SNPs) are the simplest and most common type of DNA variations in the human genome. This class of attractive genetic markers, along with point mutations, have been associated with the risk of developing a wide range of diseases, including cancer, cardiovascular diseases, autoimmune diseases, and neurodegenerative diseases. Several existing methods to detect SNPs and mutations in body fluids have faced limitations. Therefore, there is a need to focus on developing noninvasive future polymerase chain reaction (PCR)–free tools to detect low-abundant SNPs in such specimens. The detection of small concentrations of SNPs in the presence of a large background of wild-type genes is the biggest hurdle. Hence, the screening and detection of SNPs need efficient and straightforward strategies. Suitable amplification methods are being explored to avoid high-throughput settings and laborious efforts. Therefore, currently, DNA sensing methods are being explored for the ultrasensitive detection of SNPs based on the concept of nanotechnology. Owing to their small size and improved surface area, nanomaterials hold the extensive capacity to be used as biosensors in the genotyping and highly sensitive recognition of single-base mismatch in the presence of incomparable wild-type DNA fragments. Different nanomaterials have been combined with imaging and sensing techniques and amplification methods to facilitate the less time-consuming and easy detection of SNPs in different diseases. This review aims to highlight some of the most recent findings on the aspects of nanotechnology-based SNP sensing methods used for the specific and ultrasensitive detection of low-concentration SNPs and rare mutations

The National Nanotechnology Initiative: Supplement to the President’s 2017 Budget

This Supplement to the President’s Budget is the annual report of the National Nanotechnology Initiative (NNI), a partnership of 20 Federal agencies and departments with activities in nanotechnology research and development (R&D), policy, and regulation. Since the inception of the NNI in 2001, participating agencies have invested nearly 24 billion (including the President’s 2017 Budget request) in fundamental and applied nanotechnology R&D; technology transfer; world-class characterization, testing, and fabrication facilities; education and workforce development; and efforts directed at understanding and controlling the environmental, health, and safety (EHS) aspects of nanotechnology. In 2015, Federal agencies invested a total of 1.5 billion in nanotechnology-related activities. The 2017 request calls for a total investment of over $1.4 billion, affirming the important role nanotechnology continues to play in the Administration’s innovation agenda. This report highlights accomplishments over the past year, discusses activities currently underway, and outlines plans for how agencies will work both in dividually and collectively in 2017 to build upon these accomplishments and further advance the goals of the NNI

Aptamer-functionalized natural protein-based polymers as innovative biomaterials

Producción CientíficaBiomaterials science is one of the most rapidly evolving fields in biomedicine. However, although novel biomaterials have achieved well-defined goals, such as the production of devices with improved biocompatibility and mechanical properties, their development could be more ambitious. Indeed, the integration of active targeting strategies has been shown to allow spatiotemporal control of cell–material interactions, thus leading to more specific and better-performing devices. This manuscript reviews recent advances that have led to enhanced biomaterials resulting from the use of natural structural macromolecules. In this regard, several structural macromolecules have been adapted or modified using biohybrid approaches for use in both regenerative medicine and therapeutic delivery. The integration of structural and functional features and aptamer targeting, although still incipient, has already shown its ability and wide-reaching potential. In this review, we discuss aptamer-functionalized hybrid protein-based or polymeric biomaterials derived from structural macromolecules, with a focus on bioresponsive/bioactive systems.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional - Fondo Social Europeo (Proyects MAT2016-79435-R, DTS19/00162, and PID2019-106386RB-I00)Junta de Castilla y León (Project VA317P18