Gold nanorods (NRs), pseudo-one-dimensional rod-shaped nanoparticles (NPs), have become one of the burgeoning materials in the recent years due to their anisotropic shape and adjustable plasmonic properties. With the continuous improvement in synthetic methods, a variety of materials have been attached around Au NRs to achieve unexpected or improved plasmonic properties and explore state-of-the-art technologies. In this review, we comprehensively summarize the latest progress on Au NRs, the most versatile anisotropic plasmonic NPs. We present a representative overview of the advances in the synthetic strategies and outline an extensive catalogue of Au-NR-based heterostructures with tailored architectures and special functionalities. The bottom-up assembly of Au NRs into preprogrammed metastructures is then discussed, as well as the design principles. We also provide a systematic elucidation of the different plasmonic properties associated with the Au-NR-based structures, followed by a discussion of the promising applications of Au NRs in various fields. We finally discuss the future research directions and challenges of Au NRs.

Gold Nanorods: The Most Versatile Plasmonic Nanoparticles

Over the past 15 years, the field of microrobotics has exploded with many research groups from around the globe contributing to numerous innovations that have led to exciting new capabilities and important applications, ranging from in vivo drug delivery, to intracellular biosensing, environmental remediation, and nanoscale fabrication Smart responsive materials have had a profound impact on the field of microrobotics and have imparted small-scale robots with new functionalities and distinct capabilities We have identified four large categories where the majority of future efforts must be allocated to push the frontiers of microrobots and where smart materials can have a major impact on such future advances These four areas are the propulsion and biocompatibility of microrobots, the cooperation between individual units and human operators, and finally, the intelligence of microrobots In this Review, we look critically at the latest developments in these four categories and discuss how smart materials contribute to the progress in the exciting field of microrobotics and will set the stage for the next generation of intelligent and programmable microrobots

Smart Materials for Microrobots.

Nanoparticles are widely used in various fields of science and technology as well as in everyday life. In particular, gold and silver nanoparticles display unique optical properties that render them extremely attractive for various applications. In this review, we focus on the use of noble metal nanoparticles as plasmonic nanosensors with extremely high sensitivity, even reaching single molecule detection. Sensors based on plasmon resonance shifts, as well as the use of surface-enhanced Raman scattering and surface-enhanced fluorescence, will be considered in this work.

http://iopscience.iop.org/article/10.1088/0957-4484/26/32/322001/pdf

Sensing using plasmonic nanostructures and nanoparticles.

Synthetic micro- and nanomotors (MNMs) are tiny objects that can autonomously move under the influence of an appropriate source of energy, such as a chemical fuel, magnetic field, ultrasound, or light. Chemically driven MNMs are composed of or contain certain reactive material(s) that convert chemical energy of a fuel into kinetic energy (motion) of the particles. Several different materials have been explored over the last decade for the preparation of a wide variety of MNMs. Here, the discovery of materials and approaches to enhance the efficiency of chemically driven MNMs are reviewed. Several prominent applications of the MNMs, especially in the fields of biomedicine and environmental science, are also discussed, as well as the limitations of existing materials and future research directions.

/pdf/progress-toward-catalytic-micro-and-nanomotors-for-tscj7wo6yh.pdf

Progress toward Catalytic Micro- and Nanomotors for Biomedical and Environmental Applications.

An efficient water soluble fluorescent Al3+ receptor, 1-[[(2-furanylmethyl)imino]methyl]-2-naphthol (1-H) was synthesized and characterized by physico-chemical and spectroscopic tools along with single crystal X-ray crystallography. High selectivity and affinity of 1-H towards Al3+ in HEPES buffer (DMSO/water: 1/100) of pH 7.4 at 25 °C showed it to be suitable for detection of intracellular Al3+ by fluorescence microscopy. Metal ions, viz. alkali (Na+, K+), alkaline earth (Mg2+, Ca2+), and transition-metal ions (Ni2+, Zn2+, Cd2+, Co2+, Cu2+, Fe3+, Cr3+/6+, Hg2+) and Pb2+, Ag+ did not interfere. The lowest detection limit for Al3+ was calculated to be 6.03 × 10−7 M in 100 mM HEPES buffer (DMSO/water: 1/100). Theoretical calculations have also been included in support of the configuration of the probe–aluminium complex.

A water soluble Al3+ selective colorimetric and fluorescent turn-on chemosensor and its application in living cell imaging

We report the visual detection of Al3+ using unlabeled gold nanoparticles (AuNPs) based on the complexation of Al3+ with citric acid, resulting in the aggregation of AuNPs. The distinction of color change can be observed by the naked eye at concentrations down to 1.0 μM which is lower than the permissable level (7.4 μM) for drinking water as defined by the World Health Organization.

Rapid visual detection of aluminium ion using citrate capped gold nanoparticles.

The recently reported shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) is considered as the next generation of advanced spectroscopy for its surface and molecular generality. With the aim to utilize the virtues of shell-isolated strategy and advance the SHINERS technique, we introduce a silane-based rapid synthesis method of silica-coating Au nanorods (Au@SiO2 NRs) with manoeuvrable ultra-thin shell and tunable SPR. The results demonstrate that the SPR of Au NRs could be optimized to obtain large Raman enhancement using either 633 nm or 785 nm laser. Differing from previously reported Au@SiO2 NRs synthesis method, we can tune the silica shell thickness within several nanometers to maximize the Raman signal while effectively eliminating the exterior interference. And this advanced synthesis method has also significantly reduced the silica-coating time from one day to ca. 1 h. This method as a new development of SHINERS technique has successfully got enhanced signal in solution Raman tests of malachite green, giving a great potential to be extended to in-situ measurement for daily life detection. Copyright © 2013 John Wiley & Sons, Ltd.

Rapid synthesis and characterization of ultra‐thin shell Au@SiO2 nanorods with tunable SPR for shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS)

Au–Fe/Ni alloy nanowire motors, having an average length of 5.4 ± 1.2 μm and a diameter of 280 ± 10 nm, can move fast in a mixed fuel containing H2O2 and N2H4. The powered motion is attributed to the bubble thrust produced from catalytic decomposition of hydrogen peroxide on the Fe/Ni alloy segments, while hydrazine seems to act as a co-catalyst. The regulation of speed can be achieved by modulating the proportion of alloy composition, and the highest speed obtained is up to 850 μm s−1 (ca. 157 body-length per s), which is the fastest among all nanowire motors. Because of the ferronickel segment's magnetism, the Au–Fe/Ni alloy nanomotors also can be guided by the magnetic force, in addition to being controlled by the propelling force generated by the bubble thrust.

Au–Fe/Ni alloy hybrid nanowire motors with dramatic speed

We report for the first time that conducting objects could be propelled in folded liquid filled channels by bipolar electrochemistry. This approach was based on controlling the formation of hydrogen bubbles at one extremity of a bipolar electrode. In this work, copper wires used as microswimmers could move in folded channels with angles from 30° to 180° by bubble propulsion and the velocity fluctuated over time. A proportional relation between polarization voltage and average velocity in linear channel was verified. The motion of microswimmers could be controlled within these types of channels in space and time, which might broaden the applications of micromachines in bipolar electrochemistry.

/pdf/propulsion-of-copper-microswimmers-in-folded-fluid-channels-2geahcuqnf.pdf

Propulsion of copper microswimmers in folded fluid channels by bipolar electrochemistry

We previously introduced a novel Au–Fe/Ni alloy nanomotor that could move with a speed of up to 850 μm s−1 in a mixed fuel (H2O2 and N2H4) environment. However, the propulsion mechanism and the role of hydrazine were not fully elucidated. To this end, Tafel plots, linear sweep voltammetry (LSV) and oxygen sensing were employed and integrated to explore hydrazine's function and explain the locomotive behaviour of Au–Fe/Ni nanomotors. It was found that the speed of Au–Fe/Ni nanomotors was not positively correlated with the mixed potential difference between the composite metal pair, which had not been found in similar self-electrophoresis propelled nanomotors. Moreover, the results showed that the oxidation of H2O2 can also be facilitated by hydrazine in mixed fuels, resulting in oxygen bubbles propelling Au–Fe/Ni nanomotors forward.

The role of hydrazine in mixed fuels (H2O2/N2H4) for Au–Fe/Ni nanomotors

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Ju Li

Author Tools

Chat about Author