Self-Assembled Peptide Nanofibers with Voltage-Regulated Inverse Photoconductance

Hierarchical Self-Assembly of Short Peptides: Nanostructure Formation, Function Tailoring, and Applications

This article explores the hierarchical self-assembly of short peptides, which refers to the structured spatial arrangements of these molecules over long distances. This phenomenon is commonly found in nature and has important implications for biological structure and function. Short peptides are preferred for self-assembly because they have the ability to spontaneously create various nanostructures. This process, known as bottom-up assembly, allows for the addition of functional groups at the carboxyl or amine ends of the peptides. These functional groups enable specific functions that are extremely valuable in the fields of biotechnology and biomedicine. This text discusses the basic processes involved in the self-assembly of short peptides, such as the characteristics of amino acid side chains, the categorization of short peptides according to their chemical structure, the influence of intermolecular forces, and the dynamic nature of the self-assembly process. In addition, the paper discusses the various uses of short peptides in the disciplines of biomedicine and optoelectronics, including stimulus-responsive hydrogels, tissue engineering, and drug delivery. The article also suggests rational design principles for controlling the hierarchical self-assembly of short peptides, creating new commercial applications, particularly with functional hydrogels, and offers insights into the future of the discipline.

Development of Bio-Voltage Operated Humidity-Sensory Neurons Comprising Self-Assembled Peptide Memristors

Biomimetic humidity sensors offer a low-power approach for respiratory monitoring in early lung-disease diagnosis. However, balancing miniaturization and energy efficiency remains challenging. This study addresses this issue by introducing a bioinspired humidity-sensing neuron comprising a self-assembled peptide nanowire (NW) memristor with unique proton-coupled ion transport. The proposed neuron shows a low Ag+ activation energy owing to the NW and redox activity of the tyrosine (Tyr)-rich peptide in the system, facilitating ultralow electric-field-driven threshold switching and a high energy efficiency. Additionally, Ag+ migration in the system can be controlled by a proton source owing to the hydrophilic nature of the phenolic hydroxyl group in Tyr, enabling the humidity-based control of the conductance state of the memristor. Furthermore, a memristor-based neuromorphic perception neuron that can encode humidity signals into spikes is proposed. The spiking characteristics of this neuron can be modulated to emulate the strength-modulated spike-frequency characteristics of biological neurons. A three-layer spiking neural network with input neurons comprising these highly tunable humidity perception neurons shows an accuracy of 92.68% in lung-disease diagnosis. This study paves the way for developing bioinspired self-assembly strategies to construct neuromorphic perception systems, bridging the gap between artificial and biological sensing and processing paradigms.

Advances in Emerging Photonic Memristive and Memristive-Like Devices

Possessing the merits of high efficiency, low consumption, and versatility, emerging photonic memristive and memristive-like devices exhibit an attractive future in constructing novel neuromorphic computing and miniaturized bionic electronic system. Recently, the potential of various emerging materials and structures for photonic memristive and memristive-like devices has attracted tremendous research efforts, generating various novel theories, mechanisms, and applications. Limited by the ambiguity of the mechanism and the reliability of the material, the development and commercialization of such devices are still rare and in their infancy. Therefore, a detailed and systematic review of photonic memristive and memristive-like devices is needed to further promote its development. In this review, the resistive switching mechanisms of photonic memristive and memristive-like devices are first elaborated. Then, a systematic investigation of the active materials, which induce a pivotal influence in the overall performance of photonic memristive and memristive-like devices, is highlighted and evaluated in various indicators. Finally, the recent advanced applications are summarized and discussed. In a word, it is believed that this review provides an extensive impact on many fields of photonic memristive and memristive-like devices, and lay a foundation for academic research and commercial applications.