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Several seed-mediated syntheses of low symmetry anisotropic nanoparticles yield broad product distributions with multiple defect structures. This observation challenges the role of the nanoparticle precursor as a seed for certain syntheses and suggests the possibility of alternate nucleation pathways. Herein, we report a method to probe the role of the nanoparticle precursor in anisotropic nanoparticle nucleation with compositional and structural ‘labels’ to track their fate. We use the synthesis of gold triangular nanoprisms (Au TPs) as a model system. We propose a mechanism in which, rather than acting as a template, the nanoparticle precursor catalyzes homogenous nucleation of Au TPs.

The development of highly sensitive and selective methods for the detection of microRNA (miRNA) has attracted tremendous attention because of its importance in fundamental biological studies and diagnostic applications. In this work, we develop DNA-encoded Raman-active anisotropic nanoparticles modified origami paper analytical devices (oPADs) for rapid, highly sensitive, and specific miRNA detection. The Raman-active anisotropic nanoparticles were prepared using 10-mer oligo-A, -T, -C, and -G to mediate the growth of Ag cubic seeds into Ag nanoparticles (AgNPs) with different morphologies. The resulting AgNPs were further encoded with DNA probes to serve as effective surface-enhanced Raman scattering (SERS) probes. The analytical device was then fabricated on a single piece of SERS probes loaded paper-based substrate and assembled based on the principles of origami. The addition of the target analyte amplifies the Raman signals on DNA-encoded AgNPs through a target-dependent, sequence specific DNA hybridization assembly. This simple and low-cost analytical device is generic and applicable to a variety of miRNAs, allowing detection sensitivity down to 1 pM and assay time within 15 min, and therefore holds promising applications in point-of-care diagnostics.

For decades, one of the overarching objectives of self-assembly science has been to define the rules necessary to build functional, artificial materials with rich and adaptive phase behavior from the bottom-up. To this end, the computational and experimental efforts of chemists, physicists, materials scientists, and biologists alike have built a body of knowledge that spans both disciplines and length scales. Indeed, today control of self-assembly is extending even to supramolecular and molecular levels, where crystal engineering and design of porous materials are becoming exciting areas of exploration. Nevertheless, at least at the nanoscale, there are many stones yet to be turned. While recent breakthroughs in nanoparticle (NP) synthesis have amassed a vast library of nanoscale building blocks, NP-NP interactions in situ remain poorly quantified, in large part due to technical and theoretical impediments. While increasingly many applications for self-assembled architectures are being demonstrated, it remains difficult to predict-and therefore engineer-the pathways by which these structures form. Here, we describe how investigations using liquid-phase transmission electron microscopy (TEM) have begun to play a role in pursuing some of these long-standing questions of fundamental and far-reaching interest. Liquid-phase TEM is unique in its ability to resolve the motions and trajectories of single NPs in solution, making it a powerful tool for studying the dynamics of NP self-assembly. Since 2012, liquid-phase TEM has been used to investigate the self-assembly behavior of a variety of simple, metallic NPs. In this Account, however, we focus on our work with anisotropic NPs, which we show to have very different self-assembly behavior, and especially on how analysis methods we and others in the field are developing can be used to convert their motions and trajectories revealed by liquid-phase TEM into quantitative understanding of underlying interactions and dynamics. In general, liquid-phase TEM studies may help bridge enduring gaps in the understanding and control of self-assembly at the nanoscale. For one, quantification of NP-NP interactions and self-assembly dynamics will inform both computational and statistical mechanical models used to describe nanoscale phenomena. Such understanding will also lay the groundwork for establishing new and generalizable thermodynamic and kinetic design rules for NP self-assembly. Synergies with NP synthesis will enable investigations of building blocks with novel, perhaps even evolving or active behavior. Moreover, in the long run, we foresee the possibility of applying the guidelines and models of fundamental nanoscale interactions which are uncovered under liquid-phase TEM to biological and biomimetic systems at similar dimensions.

We report a simple strategy for the growth of ultra-thin magnetite nanoplates. The injection of a large portion of precursor after stunted nucleation is favorable for both the survival of metastable structures in seeds and their subsequent development into anisotropic nanoparticles. The as-synthesized ultrathin triangular magnetite nanoplates are expected to have important applications as T1 contrast agents for magnetic resonance imaging.

Characterizing the morphometric parameters of noble metal nanoparticles for sensing and catalysis is a persistent challenge due to their small size and complex shape. Herein, we present an approach to determine the volume, surface area, and curvature of non-symmetric anisotropic nanoparticles using electron tomography and design- based stereology without the use of segmentation tools or modeling of the particles. Finally, we apply these tools to aggregates to estimate their fractal dimension.

Anisotropic gold nanoparticles (Au NPs) have been synthesized via a green route with the aid of Malva parviflora (M. parviflora) extract. Their UV-vis-NIR spectra exhibit a near infrared absorption feature, which is due to the one-dimensional growth of Au NPs. The images of transmission electron microscopy (TEM) show that the Au NPs are triangular in shape. The formation of Au anisotropic nanoparticles was found to depend on the extract quantity. The Au NPs show good antibacterial activity against the Gram-positive bacteria Bacillus subtilis and Enterococcus faecalis.

The rational design of anisotropic interaction patterns is a key step for programming colloid and nanoparticle self-assembly and emergent functions. Herein, we demonstrate a concept for harnessing the capabilities of 3D DNA origami for extensive supracolloidal self-assembly and showcase its use for making truly monodisperse, patchy, divalent nanocuboids that can self-assemble into supracolloidal fibrils via programmable DNA hybridization. A change in the number of connector duplexes at the patches reveals that multivalency and cooperativity play crucial roles to enhance superstructure formation. We further show thermal and chemical switching of the superstructures as the first steps toward reconfigurable self-assemblies. This concept lays the groundwork for merging monodisperse 3D DNA origami, featuring programmable patchiness and interactions, with nanoparticle self-assembly.

International audience; Periodic arrays of anisotropic silver nanoparticles having peculiar optical properties are fabricated at a macroscopic scale. The proposed scalable method is based on temperature‐assisted solid‐state dewetting of a continuous thin layer deposited on a silica substrate patterned by the nanoimprint technique. The resulting nanoparticles are shaped like diamonds and are half‐embedded into the patterned silica. A period‐dependent optimum in film thickness for the quality of spatial organization is found and discussed in terms of thermodynamics and, for the first time, in terms of the role of grains in the dewetting process. The optical properties of the arrays are driven by not only simply the particle shape but also the lattice period and the degree of order. A surface lattice resonance that disperses with the underlying period is evidenced experimentally and confirmed by optical simulations. The opportunity to fabricate and tune such an assembly of plasmonic particles on transparent substrate opens interesting perspectives for not only fundamental photonics but also potential optical applications.

Ion-induced assemblies of highly anisotropic nanoparticles can be explained by a model consisting of ion–ion correlation and specific ion effects: dispersion interactions, metal–ligand complexes, and local acidic environments. Films of cellulose nanofibrils and montmorillonite clay were treated with different ions, and their subsequent equilibrium swelling in water was related to important parameters of the model in order to investigate the relative importance of the mechanisms. Ion–ion correlation was shown to be the fundamental attraction, supplemented by dispersion interaction for polarizable ions such as Ca2+ and Ba2+, or metal–ligand complexes for ions such as Cu2+, Al3+ and Fe3+. Ions that form strong complexes induce local acidic environments that also contribute to the assembly. These findings are summarized in a comprehensive semi-quantitative model and are important for the design of nanomaterials and for understanding biological systems where specific ions are involved.

Understanding and controlling self-assembly processes at multiple length scales is vital if we are to design and create advanced materials. In particular, our ability to organise matter on the nanoscale has advanced considerably, but still lags far behind our skill in manipulating individual molecules. New tools allowing controlled nanoscale assembly are sorely needed, as well as the physical understanding of how they work. Here, we report such a method for the production of highly anisotropic nanoparticles with controlled dimensions based on a morphological transformation process (MORPH, for short) driven by the formation of supramolecular bonds. We present a minimal physical model for MORPH that suggests a general mechanism which is potentially applicable to a large number of polymer/nanoparticle systems. We envision MORPH becoming a valuable tool for controlling nanoscale self-assembly, and for the production of functional nanostructures for diverse applications., Understanding and controlling self-assembly processes at multiple length scales is essential to design and create advanced materials. Here the authors report a method for the production of highly anisotropic nanoparticles with controlled dimensions based on the morphological transformation of initially isotropic seeds, driven by supramolecular bonding.

The latest breakthroughs in the synthetic preparation of nanomaterials have led to an expanding library of novel, complex and shape controlled structures with unique characteristics. Anisotropic Janus particles (JPs) are asymmetrical and are able to endow diverse chemical and physical characteristics with directionality within a single particle. They are typically distributed into three classes, viz polymeric, inorganic and polymeric-inorganic and is made in a variation of morphologies including spherical, mushroom, snowman shaped, rod or cylindrical. Herein, we focus on JPs with a magnetic component, with emphasis on their fabrication, unique characteristics and recent applications.

Anisotropic nanoparticles are powerful building blocks for materials engineering. Unusual properties emerge with added anisotropy-often to an extraordinary degree-enabling countless new applications. For bottom-up assembly, anisotropy is crucial for programmability; isotropic particles lack directional interactions and can self-assemble only by basic packing rules. Anisotropic particles have long fascinated scientists, and their properties and assembly behavior have been the subjects of many theoretical studies over the years. However, only recently has experiment caught up with theory. We have begun to witness tremendous diversity in the synthesis of nanoparticles with controlled anisotropy. In this Perspective, we highlight the synthetic achievements that have galvanized the field, presenting a comprehensive discussion of the mechanisms and products of both seed-mediated and alternative growth methods. We also address recent breakthroughs and challenges in regiospecific functionalization, which is the next frontier in exploiting nanoparticle anisotropy.

Electrospinning is a very simple, robust, and versatile technique to process solutions or melts into continuous fibres with diameters down to the nanoscale, which has attracted much attention in both research and commerce. Up to now, a rich variety of electrospun fibres with controllable morphology, alignment and composition have been synthesized, and the materials composed of functional electrospun fibres have already been successfully applied in many technological areas. In particular for anisotropic nanoparticles (NPs), electrospinning shows its powerful capability to assemble them on a large scale. The goal of this brief focus article is to show you how to use the electrospinning technique for preparing the functional fibres you want.

The 191st Faraday Discussion meeting on “Nanoparticles with Morphological and Functional Anisotropy” offers a broad range of new insights into an interdisciplinary research field converged at the forefronts of chemistry, colloid science, and materials science. It was held on the campus of University of Strathclyde, Glasgow, UK. Across the street of the meeting place, one could see a large portrait of Thomas Graham, the father of physical chemistry who coined the term of “colloid” in the 19th century, painted on the outside wall of a tall building. Without any doubt, he would also have enjoyed listening to the fascinating progress in a research field pioneered by him. The discussion was organized into four sessions, with each session covering a specific theme: (i) Janus and patchy nanoparticles; (ii) anisotropic nanoparticles; (iii) particles at interfaces; and (iv) applications. The meeting was further enriched by the presentation of 79 posters. Instead of giving a summary of what was presented at the meeting, I would like to take this opportunity to provide some personal perspectives, in conjunction with the insights offered by various authors.

Superior spectral sensitivity and functional abilities of anisotropic, instead of the usually used spherical, noble metal nanoparticles, allow development of new surface-enhanced Raman spectroscopy (SERS) approaches to analyse biological objects. We found and resolved for the first time the particular risks of survival of silver nanoparticles in different salines to succeed in recording the SERS spectra of intact erythrocytes as an important family of living cells. The ensemble of nanoplatelets with varied shapes and sizes grants multispectral absorption of laser irradiation since a fraction of the nanoparticles with a given position of a plasmonic band always exists in such a mixture, thereby providing an effective SERS amplification. At the same time, fast recrystallization of anisotropic silver nanoplatelets occurs in a standard chloride-based saline, being important to keep the erythrocytes alive but neglecting the benefits of the silver platelets as the most versatile and prospective components of SERS sensors. Substitution of chlorides with nitrates keeps both the intact cells and anisotropic nanoparticles safe on biocompatible cellulose SERS scaffolds containing the mixture of silver nanoplatelets thus promoting the development of new SERS devices for biomedical diagnostics.

A sensitive fluorescent analytical method for the detection of dopamine (DA) was developed based on surface-enhanced Tb(III)/La(III) co-luminescence using silver nanoflowers (AgNFs). Anisotropic AgNFs show strong surface-enhanced fluorescence effect owing to the abundant sharp tips. Tb(III)/La(III)-DA complexes mainly bind to the sharp tips of AgNFs and thus shorten the distance between the complexes. The shortened distance gives rise to obvious surface-enhanced Tb(III)/La(III) co-luminescence effect. In this work, AgNFs offer many superior properties, such as enhanced intrinsic green fluorescence of Tb(III) (λex/λem = 310/546 nm), increased fluorescence lifetime, and improved energy transfer efficiency. Under the optimum conditions, the fluorescence intensity is linearly correlated with the concentration of DA in the range of 0.80–10 nM (R2 = 0.9970), and the detection limit is 0.34 nM (S/N = 3). The fluorescent nanoprobe was successfully applied to the determination of DA in human serum samples with recoveries ranging from 99.1 to 102.6%.

We report on the widening of blue phase range induced by surface-functionalised laponite nanoplatelets dispersed in a chiral liquid crystal. The results are obtained by means of high-resolution ac calorimetry and optical microscopy and they are reproducible upon heating and cooling, identifying thermodynamically stable blue phases. It is shown that nanoplatelets target mostly the cubic structure of blue phase I and increase its temperature stability range by a factor of two. The present results are in agreement with recent findings that anisotropic nanoparticles tend to effectively stabilise blue phase I.

Au nanorods are optically tunable anisotropic nanoparticles with built-in catalytic activities. The state-of-the-art seed-mediated nanorod synthesis offers excellent control over the aspect ratios of cylindrical Au nanorods, which enables fine-tuning of plasmon resonances over a broad spectral range. However, facet control of Au nanorods with atomic-level precision remains significantly more challenging. The coexistence of various types of low-index and high-index facets on the highly curved nanorod surfaces makes it extremely challenging to quantitatively elucidate the atomic-level structure-property relationships that underpin the catalytic competence of Au nanorods. Here we demonstrate that cylindrical Au nanorods undergo controlled facet evolution during their overgrowth in the presence of Cu(2+) and cationic surfactants, resulting in the formation of anisotropic nanostructures enclosed by well-defined facets, such as low-index faceting nanocuboids and high-index faceting convex nanocuboids and concave nanocuboids. These faceted Au nanorods exhibit enriched optical extinction spectral features, broader plasmonic tuning range, and enhanced catalytic tunability in comparison to the conventional cylindrical Au nanorods. The capabilities to both fine-tailor the facets and fine-tune the plasmon resonances of anisotropic Au nanoparticles open up unique opportunities for us to study, in great detail, the facet-dependent interfacial molecular transformations on Au nanocatalysts using surface-enhanced Raman scattering as a time-resolved spectroscopic tool.

The manuscript deals with the green synthesis of anisotropic silver nanoparticles (AgNPs). For synthesis, the maltose has been used as reducing and polyvinyl pyrrolidone (PVP) as capping agent and the reaction has been initiated using microwave heating. A strong SPR band at 427 nm and a tail around 590 nm in UV–Vis spectrum of AgNPs, and TEM imaging confirmed the synthesis of anisotropic nanoparticles (NPs). Microwave irradiation time, silver precursor concentration and capping agent concentration affected the particle size as well as particle size distribution. Antibacterial behaviour of anisotropic AgNPs was better than their spherical counterparts.

Anisotropic nanoparticles show unusual and extraordinary physical and chemical properties. Herein, we report a simple and facile seeded growth strategy for the synthesis of highly complex flower-like gold nanoparticles with plasmon resonance band at around 650 nm. The high electromagnetic fields achieved at specific locations of the synthesized gold nanoflowers are found to be very efficient SERS substrates, especially with an incubation time of 24 hours.

Cubic frame–like superstructures are constructed via the assembly of nanocuboids on the edges of preformed nanocubes., It is fascinating but challenging for nanoscientists to organize nanoparticles (NPs) into ordered architectures just as it is for chemists to manipulate atoms and molecules to form functional molecules and supramolecules. We explore a strategy to assemble anisotropic NPs into open frame-like superstructures via oriented attachment (OA), experimentally realizing a nanoscale analog to the bonding behavior in M8L12-type supramolecular cubes. We highlight the role of NP shape in the OA-involved assembly for constructing predictable superstructures. In addition, the frame-like superstructures can retain their basic structure when undergoing postcrystallization of the building blocks as well as annealing for conversion toward functional electrocatalytic materials. Our work enables fundamental insights into directional “bonding” among NPs and adds to the growing body of knowledge for bottom-up assembly of anisotropic NPs into sophisticated functional materials.

Directed assemblies of anisotropic metal nanoparticles exhibit attractive physical and chemical properties. However, an effective methodology to prepare differently directed assemblies from the same anisotropic nanoparticles is not yet available. Gold nanorods (AuNRs) region-selectively modified with different DNA strands can form side-by-side (SBS) and end-to-end (ETE) assemblies in a non-crosslinking manner. When the complementary DNA is hybridized to the surface-bound DNA, stacking interaction between the blunt ends takes place in the designated regions. Such AuNRs assemble into highly ordered structures, assisted by capillary forces emerging on the substrate surface. Moreover, insertion of a mercury(II)-mediated thymine-thymine base pair into the periphery of the DNA layer allows selective formation of the SBS or ETE assemblies from the strictly identical AuNRs with or without mercury(II).

This review summarizes recent advances on design strategies for shape-controlled anisotropic gold nanoparticles. Detailed chemical mechanism has been discussed to understand the anisotropic growth. The effect of various chemical parameters and surface facets for the formation of different shaped anisotropic nanoparticles have been addressed.

Nanoscale materials formed by logical or random ensembles of molecules have been an integral part of many cultures for centuries, although arguably for thousands of years. Early notable works with nanomaterials date back all the way to the 9th century, as artisans and pot-makers would apply metallic films on the surface of ceramics, rendering a metallic glitter to their works.

Many nanoparticle adsorption processes are dictated by the collective interactions of surface-bound ligands. These adsorption processes define how nanoparticles interact with biological systems and enable the assembly of nanoparticle- based materials and devices. Herein, we present an approach for quantifying nanoparticle adsorption thermodynamics in a manner that satisfies the assumptions of the Langmuir model. Using this approach, we study the DNA-mediated adsorption of polyvalent anisotropic nanoparticles on surfaces and explore how deviations from model assumptions influence adsorption thermodynamics. Importantly, when combined with a solution-based vant Hoff analysis, we find that poly- valency plays a more important role as the individual interactions become weaker. Furthermore, we find that the free energy of anisotropic nanoparticle adsorption is consistent across multiple shapes and sizes of nanoparticles based on the surface area of the interacting facet. Molecular adsorption models are used to quantify surface coverage of molecular species, to characterize adsorption kinetics, and to evaluate the interaction thermodynamics between a molecular adsorbate and a surface site on an adsorbent. The most common molecular-adsorption model

The growth process of nonspherical nanoparticles on preliminarily synthesized gold-silver seeds in micellar surfactant media is studied in this article. The effect of experimental factors, such as the concentration of initial compounds and formation of intermediate insoluble compounds, on nanoparticle size and geometry in the output sole is investigated. It is concluded that the slow generation of silver ions, causing layer-by-layer directed growth, is a necessary factor of anisotropic nanoparticles formation. The optimized parameters of synthesis enable one to control the geometry of final sols and increase the yield of resulting anisotropic nanoparticles.

Gold nanoparticles were synthesized using Ananas comosus as reducing agent. UV–visible spectra show the surface plasmon resonance peak at 546 nm. TEM measurement shows that the formation of little anisotropic nanoparticles with average size of 16 nm. Crystalline nature of the nanoparticles was evident from TEM images and peaks in the XRD pattern. The prepared gold nanoparticles reveal good antibacterial activity against gram positive and negative pathogens , which are found in water. So the prepared nanoparticles have found applications in water purification processes for inhibiting the growth of bacteria.

By the common seed-mediated growth method, the preparation of silver nanostructures with desired morphologies still remains a great challenge. In this paper, the same growth solution was used to prepare the desired anisotropic nanoparticles through different preparation procedures of silver seeds and nanoparticles. The citrate-capped silver seeds (common seeds) were confirmed to grow and aggregate to form silver nanorods in CTAB rod-like micelles by a common seed-mediated method (one-step growth). The interesting difference from the above method was that silver nanodisks were obtained by three-step growths of the seeds. Silver nanotriangles could be easily prepared with modified silver seeds that prepared by only changing the molar ratio of NaBH4 to silver precursor and other conditions were the same as those in the preparation of common silver seeds. Furthermore, the yield of silver nanotriangles had a marked increase by adding Cl− into the growth solution of silver nanotriangles. In addition, the silver seeds capped with BSPP gradually grew up to form irregular polygon-shaped nanodisks with clear multiple-twinned structure. The proposed strategies hold great potential to be extended in the preparation of silver and other metal nanoparticles with different shapes.

Anisotropic nanoparticles (i.e., silver nanocubes) were functionalized with target-specific antibodies and Raman active tags to serve as nanoprobes for the rapid detection of bacteria in a test-in-a-tube platform. A self-referencing scheme was developed and implemented in which surface enhanced Raman spectroscopic (SERS) signatures of the targets were observed superimposed with the SERS signals of the Raman tags. The assessment through the dual signals (superimposed target and tag Raman signatures) supported a specific recognition of the targets in a single step with no washing/separation needed to a sensitivity of 102 CFU/mL, even in the presence of non-target bacteria at a 10 times higher concentration. The self-referencing protocol implemented with a portable Raman spectrometer potentially can become an easy-to-use, field-deployable spectroscopic sensor for onsite detection of pathogenic microorganisms.

The spontaneous self-organization of dissimilar ligands on the surface of metal nanoparticles is a very appealing approach to obtain anisotropic "spherical" systems. In addition to differences in ligand length and end groups, a further thermodynamic driving force to control the self-assembled monolayer organization may become available if the ligands are inherently immiscible, as is the case of hydrogenated (H-) and fluorinated (F-) species. Here, we validate the viability of this approach by combining (19)F NMR experiments and multiscale molecular simulations on large sets of mixed-monolayer-protected gold nanoparticles (NPs). The phase segregation of blends of F- and H-thiolates grafted on the surface of gold NPs allows a straightforward approach to patterned mixed monolayers, with the shapes of the monolayer domains being encoded in the structure of the F/H-thiolate ligands. The results obtained from this comprehensive study offer molecular design rules to achieve a precise control of inorganic nanoparticles protected by specifically patterned monolayers.

Anisotropic nanoparticles prepared from block copolymers are of growing importance as building blocks for the creation of synthetic hierarchical materials. However, the assembly of these structural units is generally limited to the use of amphiphilic interactions. Here we report a simple, reversible coordination-driven hierarchical self-assembly strategy for the preparation of micron-scale fibres and macroscopic films based on monodisperse cylindrical block copolymer micelles. Coordination of Pd(0) metal centres to phosphine ligands immobilized within the soluble coronas of block copolymer micelles is found to induce intermicelle crosslinking, affording stable linear fibres comprised of micelle subunits in a staggered arrangement. The mean length of the fibres can be varied by altering the micelle concentration, reaction stoichiometry or aspect ratio of the micelle building blocks. Furthermore, the fibres aggregate on drying to form robust, self-supporting macroscopic micelle-based thin films with useful mechanical properties that are analogous to crosslinked polymer networks, but on a longer length scale., Anisotropic nanoparticles made from block copolymers are important building blocks for synthetic hierarchical materials. Here, the authors report a reversible coordination-driven self-assembly strategy for the preparation of micron-scale fibres and macroscopic films based on monodisperse cylindrical micelles.

We demonstrate that radial anisotropy can be employed to tune effectively the spectral positions of electric resonances of nanoparticles, which enables flexible overlapping of electric and magnetic dipoles of various numbers and thus leads to unidirectional forward superscattering. We further reveal that through adjusting the radial anisotropy parameters, electric and magnetic resonances of higher orders can be also made overlapped, thus further collimating the forward scattering lobes.

Review of Nanofluid Applications Kaufui V. Wong and Omar De Leon The Role of Nanoparticle Suspensions in Thermo/Fluid and Biomedical Applications Khalil M. Khanafer and Kambiz Vafai Multiscale Simulation of Nanoparticle Transport in Deformable Tissue during an Infusion Process in Hyperthermia Treatments of Cancers Ronghui Ma, Di Su, and Liang Zhu Superparamagnetic Iron Oxide Nanoparticle Heating: A Basic Tutorial Michael L. Etheridge, Navid Manuchehrabadi, Rhonda R. Franklin, and John C. Bischof Light-Induced Energy Conversion in Liquid Nanoparticle Suspensions Patrick E. Phelan, Robert Taylor, Ronald J. Adrian, Ravi S. Prasher, and Todd P. Otanicar Radiative Properties of Micro/Nanoscale Particles in Dispersions for Photothermal Energy Conversion Qunzhi Zhu and Zhuomin M. Zhang On the Thermophysical Properties of Suspensions of Highly Anisotropic Nanoparticles with and without Field-Induced Microstructure Jerry W. Shan, Anna S. Cherkasova, Chen Lin, and Corinne S. Baresich Advances in Fluid Dynamic Modeling of Microfiltration Processes John E. Wentz, Richard E. DeVor, and Shiv G. Kapoor Computational Analysis of Enhanced Cooling Performance and Pressure Drop for Nanofluid Flow in Microchannels Clement Kleinstreuer, Jie Li, and Yu Feng Natural Convection in Nanofluids Massimo Corcione Index

The multimodality theranostic system, which can integrate two or more different therapeutic modalities and multimodal imaging agents into a nanoentity, shows great promising prospects for the cancer treatment. Herein, we developed an efficient and novel strategy to synthesize hybrid anisotropic nanoparticles (HANs) with intrinsic multimodal theranostic capability [chemotherapy, photothermal therapy, magnetic resonance imaging (MRI), and photoacoustic imaging (PAI)]. For the first time, under the guidance of MRI and PAI, the chemotherapy and thermotherapy induced by administration of multifunctional hybrid nanoprobes were applied simultaneously to the treatment of colon cancer-bearing mice in vivo.

21 p.-3 fig.-1 tab.-9 fig. supl., Understanding protein amyloidogenesis is an important topic in protein science, fueled by the role of amyloid aggregates, especially oligomers, in the etiology of a number of devastating human degenerative diseases. However, the mechanisms that determine the formation of amyloid oligomers remain elusive due to the high complexity of the amyloidogenesis process. For instance, gold nanoparticles promote or inhibit amyloid fibrillation. We have functionalized gold nanorods with a metal-chelating group to selectively immobilize soluble RepA-WH1, a model synthetic bacterial prionoid, using a hexa-histidine tag (H6). H6-RepA-WH1 undergoes stable amyloid oligomerization in the presence of catalytic concentrations of anisotropic nanoparticles. Then, in a physically separated event, such oligomers promote the growth of amyloid fibers of untagged RepA-WH1. SERS spectral changes of H6-RepA-WH1 on spherical citrate-AuNP substrates provide evidence for structural modifications in the protein, which are compatible with a gradual increase in β-sheet structure, as expected in amyloid oligomerization., Research at the R.G.laboratory was supported by MINECO grants CSD2009-00088, BIO2012-30852 and BIO2015-68730-R. Research at the A.G-M. and L.M.L-M. laboratories was supported by MINECO (MAT2014-59678-R and MAT2013-46101-R), Madrid Regional Government (S2013/MIT-2807) and the “I Convocatoria de Ayudas Fundación BBVA a Investigadores,Innovadores y Creadores Culturales”(14_CBB_147) grants.A.G-M. and G.G-R. acknowledge,respectively,receipt of Ramón y Cajal and FPI Fellowships from the Spanish MINECO.

International audience; Pas de résumé

An approach to unequivocally determine the three-dimensional orientation of optically manipulated NaYF4:Er3+,Yb3+ upconverting nanorods (UCNRs) is demonstrated. Long-term immobilization of individual UCNRs inside single and multiple resonant optical traps allow for stable single UCNR spectroscopy studies. Based on the strong polarization dependent upconverted luminescence of UCNRs it is possible to unequivocally determine, in real time, their three-dimensional orientation when optically trapped. In single-beam traps, polarized single particle spectroscopy has concluded that UCNRs orientate parallel to the propagation axis of the trapping beam. On the other hand, when multiple-beam optical tweezers are used, single particle polarization spectroscopy demonstrated how full spatial control over UCNR orientation can be achieved by changing the trap-to-trap distance as well as the relative orientation between optical traps. All these results show the possibility of real time three-dimensional manipulation and tracking of anisotropic nanoparticles with wide potential application in modern nanobiophotonics, This work was supported by the Spanish Ministerio de Educación y Ciencia (MAT2013-47395-C4-1-R) and by Banco Santander for “proyectos de cooperación interuniversitaria” (2015/ ASIA/06). Patricia Haro-González thanks the Spanish Ministerio de Economía y Competitividad (MINECO) for the Juan de la Cierva program. Paloma Rodríguez-Sevilla thanks the Spanish Ministerio de Economía y Competitividad (MINECO) for the “Promoción del talento y su Empleabilidad en I+D+i” statal program. Dominika Wawrzyńczyk, Marcin Nyk and Marek Samoć acknowledge the support from the National Science Centre under grant DEC-2012/04/M/ST5/00340, by a statutory activity subsidy from the Polish Ministry of Science and Higher Education for the Faculty of Chemistry of Wroclaw University of Technology, as well as from the Foundation for Polish Science under START 2014 programme. This work has received funding from The Royal Society (IE130466). Mark D. Mackenzie acknowledges funding from EPSRC (grant no EP/J500227/1

Keeping track: By combining differential interference contrast (DIC) image pattern recognition with DIC polarization anisotropy, the exact full three-dimensional angular information of individual tilted gold nanorods positioned in the focal plane of the objective lens can be readily determined. The angular rotational modes and kinetics of individual in-focus gold nanorods can thus be resolved dynamically.