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Adaptable and sensitive materials are essential for the development of advanced sensor systems such as bio and chemical sensors. Biomaterials can be used to develop multifunctional biosensor applications using genetic engineering. In particular, a plasmonic sensor system using a coupled film nanostructure with tunable gap sizes is a potential candidate in optical sensors because of its simple fabrication, stability, extensive tuning range, and sensitivity to small changes. Although this system has shown a good ability to eliminate humidity as an interferant, its performance in real-world environments is limited by low selectivity. To overcome these issues, we demonstrated the rapid response of gap plasmonic color sensors by utilizing metal nanostructures combined with genetically engineered M13 bacteriophages to detect volatile organic compounds (VOCs) and diagnose lung cancer from breath samples. The M13 bacteriophage was chosen as a recognition element because the structural protein capsid can readily be modified to target the desired analyte. Consequently, the VOCs from various functional groups were distinguished by using a multiarray biosensor based on a gap plasmonic color film observed by hierarchical cluster analysis. Furthermore, the lung cancer breath samples collected from 70 healthy participants and 50 lung cancer patients were successfully classified with a high rate of over 89% through supporting machine learning analysis.

Plasmonic nanoparticle clusters promise to support unique engineered electromagnetic responses at optical frequencies, realizing a new concept of devices for nanophotonic applications. However, the technological challenges associated with the fabrication of three-dimensional nanoparticle clusters with programmed compositions remain unresolved. Here, we present a novel strategy for realizing heterogeneous structures that enable efficient near-field coupling between the plasmonic modes of gold nanoparticles and various other nanomaterials via a simple three-dimensional coassembly process. Quantum dots embedded in the plasmonic structures display ∼56 meV of a blue shift in the emission spectrum. The decay enhancement factor increases as the total contribution of radiative and nonradiative plasmonic modes increases. Furthermore, we demonstrate an ultracompact diagnostic platform to detect M13 viruses and their mutations from femtoliter volume, sub-100 pM analytes. This platform could pave the way toward an effective diagnosis of diverse pathogens, which is in high demand for handling pandemic situations.

Bacteria are microscopic, single-celled organisms that utilize a variety of nanofluidic structures. One of the best known and widely used nanofluidic structures that are derived from bacteria is the alpha-hemolysin pore. This pore, which self-assembles in lipid bilayers, has been used for a wide variety of sensing applications, most notably, DNA sensing. Synthetic pores drilled in a wide variety of materials, such as silicon nitride and polymers have been developed that use inspiration from the alpha-hemolysin pore. Higher-aspect-ratio nanofluidic structures, akin to nanotubes, are also synthesized by bacteria. Examples of such structures include those that are associated with bacterial transport apparatus, such as pili, and are used by bacteria to facilitate the transfer of genetic material from one bacterium to another. Flagella, and its associated structures, such as the rod and hook, are also tubular nanostructures, through which the protein, flagellin, travels to assemble the flagellum. Genetic engineering allows for the creation of modified bacterial nanopores and nanotubes that can be used for a variety of medical and engineering purposes.

Self‐assembled colloidal nanostructures enable various interesting fabrication alternatives to current top‐down lithographic approaches for supporting localized surface plasmon resonance (LSPR). Recently, there have been numerous efforts to manipulate the LSPR in structural or compositional engineering using clustered nanoparticles (NPs). However, creating heterogeneous colloidal clusters comprising two or more types of NPs requires a complicated chemical synthesis of the linker molecules on the NP surfaces. Moreover, the traditional assembly methods pose several challenges to 3D manufacturing. Herein, a fountain pen‐inspired open‐microfluidic approach demonstrating an exquisite balance between evaporation and capillary action is reported. This approach enables the direct writing of binary NP clusters. Microcapillaries are designed to precisely control the evaporation and capillary action of the binary NP suspension ink at the tip. This approach effectively guides the growth of NP clusters along the out‐of‐plane direction to fabricate a freeform microarchitecture. The growth characteristics are theoretically explained using a simplified balancing model. In addition, the optical properties can be tuned precisely using multicolloidal NP mixing. A Janus pillar comprising plasmonic NPs and biomolecules is showcased as a microactuator operating under chemical stimuli. It is expected that the proposed method paves the way for manufacturing numerous interesting structures in nanophotonics. [ABSTRACT FROM AUTHOR]

In recent years, naturally occurring compounds found in plants (also known as phytochemicals) have found increasing application in the synthesis of metal oxide nanostructures due to their multi-role as reducing agents, capping agents, and/or complexing agents. Furthermore, the utilization of natural agents, such as phytochemicals provide a green and sustainable way for fabricating metal oxide nanostructures compared to conventional chemical methods. This perspective will cover various types of plant-derived phytochemicals which have been employed in the preparation of metal oxide nanostructures, including their roles and the associated formation mechanisms. This review will also discuss some prospective applications of phytochemical-derived metal oxide nanostructures for energy storage, environmental remediation, and bio-related applications. Finally, some perspectives on the future direction of the synthesis of metal oxide nanostructures via green chemistry will be provided. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF)‐derived nanoporous carbon materials have attracted significant interest due to their advantages of controllable porosity, good thermal/chemical stability, high electrical conductivity, catalytic activity, easy modification with other elements and materials, etc. Thus, MOF‐derived carbons have been used in numerous applications, such as environmental remediations, energy storage systems (i.e. batteries, supercapacitors), and catalysts. To date, many strategies have been developed to enhance the properties and performance of MOF‐derived carbons. Herein, we introduce and summarize recent important approaches for advanced MOF‐derived carbon structures with a focus on precursor control, heteroatom doping, shape/orientation control, and hybridization with other functional materials. [ABSTRACT FROM AUTHOR]