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JAPAN – Potential drug for treating chronic pain with few side effects.

AUSTRALIA – Fellowship supports search for new disease treatments.

TAIWAN – A novel platform for neurodegenerative disease studies: Applying photocontrollable probe to induce pathological proteins into amyloid fibers in live cells.

TAIWAN – CLEC5A is critical in innate immunity against bacterial infections.

SINGAPORE – Singapore scientists uncover how neural stem cells are activated intrinsically by spindle matrix proteins.

SINGAPORE – NUS establishes additive manufacturing facilities for biomedical applications.

SINGAPORE & GERMANY – Breakthrough immunotherapy for Chronic Hepatitis B virus infection.

SINGAPORE, HONG KONG & SOUTH KOREA – First in Asia - Launch of multi-centre lung cancer research platform.

SINGAPORE & TAIWAN – ASLAN Pharmaceuticals collaborates with Academia Sinica’s Genomic Research Centre.

GERMANY – ASIT biotech announces follow-up study of Phase I/IIa clinical trial for house dust mite rhinitis.

USA – Test uses nanotechnology to quickly diagnose Zika virus.

The photoluminescence of gold nanorod-quantum dots complexes was investigated in order to find optimal conditions for the luminescence enhancing. The number of quantum dots and polyelectrolyte layers on the gold nanorod surface in these complexes were considered as main factors in the enhancement.

Photoluminescent properties of CdSe/ZnS nanocrystals (quantum dots, QDs) in complexes with elongated gold nanoparticles was found to be dependent on the effective refractive index of the medium. It has been experimentally shown that changes in the refractive index make possible to increase the photoluminescence intensity by several times.

Gold nanoparticle assemblies show a strong plasmonic response due to the combined effects of the individual nanoparticles’ plasmon modes. Increasing the number of nanoparticles in structured assemblies leads to significant shifts in the optical and physical properties. We use finite-difference time-domain (FDTD) simulations to analyze the electromagnetic response of structurally ordered gold nanorods in monomer and dimer configurations. The plasmonic coupling between nanorods in monomers or dimers configurations provides a unique technique for tuning the spectrum intensity, spatial distribution and polarization of local electric fields within and surrounding nanostructures. This study shows an exponential coupling behavior when two gold nanorods are assembled in end-to-end and side-by-side dimer configurations with a small separation distance. The maximum electric field in the gaps between adjacent nanorods in end-to-end dimer configuration describes a more significant enhancement factor than the individual gold nanorod. Our FDTD simulation on dimer in end-to-end assembly for small separation distance up to $\sim 40$nm can well explain the observed experimental growth dynamics of gold nanorods.

The sulfonated aluminum phthalocyanines (AlPcSs), popularly used photosensitizers, were linked on the surfaces of gold nanorods (AuNRs) by the electrostatic binding to form AlPcS–AuNRs conjugates, in order to improve the photo-therapy efficiency of cancer cells by combining the photodynamic therapy (PDT) of AlPcSs and the photothermal therapy (PTT) of AuNRs. The AlPcS's fluorescence is two-fold enhanced when they adhered on the surfaces of AuNRs probably due to the surface Plasmon coupling, which would facilitate the AlPcS detection. The fluorescence images show that AuNRs can carry loaded AlPcSs to penetrate into human nasopharyngeal carcinoma cells with a fast speed, achieving the effective intracellular delivery of AlPcSs. The PTT effect of cellular AuNRs alone under the white light irradiation of 50 minutes decreased the cell viability to 77%, and the PDT effect of cellular AlPcS–AuNRs with filtered red light (670–710 nm) irradiation of 50 min lowered the cell viability to 79%. However, with the same white light irradiation of 50 min, the AlPcS–AuNRs destroyed most cells leaving the cell viability to 28%, reflecting a typical synergistic effect on cell killing. These results suggest that the combination of PTT and PDT with AlPcS–AuNRs is a promising strategy for improving the phototherapy of cancers.

A novel core–shell hybrid nanostructure was constructed by employing gold nanorod (AuNR) combined with rhodamine B (RB) as a core and silica as a shell. The poly(sodium 4-styrenesulfonate) (PSS), a negatively charged polyelectrolyte, played the role of linker to electrostatically trap RB on AuNRs. Due to the fluorescence spectral overlap between RB and AuNRs at 560 nm, the red fluorescence and enhanced green fluorescence of the hybrid nanostructures were observed obviously, which is capable for dual-color labeling. To reduce toxic side effects of AuNRs, silica was coated on AuNRs as a shell to fabricate the novel core–shell hybrid nanostructure function as a dual-color labeling for cancer-cell imaging. The fabricated composite structures were characterized by transmission electron microscopy (TEM), absorption spectrum, fluorescence spectrum, zeta potential measurements and laser scanning confocal microscope (LSCM). The experiment results confirmed that the obtained hybrid nanostructures provided excellent photostability, biocompatibility and active surface for further biological functionalization. The novel composite structures may have great potential application in cell multicolor labeling and imaging instead of traditional fluorescent dyes.

Self-assembly of nanoparticles has attracted more attention in the last decade due to their potential applications in many fields, such as sensors, surface-enhanced Raman scattering (SERS) substrate and optical/plasmonic components. Wrinkles, as one kind of common natural surface, are used to be a template/substrate in microfluidic sieves and solar cells. In this work, a wrinkled template with depth of about 200 nm and period of 1.64 μm is used for modulating the self-assembly process of gold nanorods (GNRs) to obtain patterned self-assemblies for potential application. In order to fully reflect the role of the wrinkled template in the self-assembly, the templates are placed uprightly in the GNRs solution to intensify the interplay between the wrinkled surface and nanorods. The self-assembly process is carried out in a climate chamber, where the temperature and humidity can be controlled programmingly to modulate the self-assembly conditions. The experimental results show that for the fixed wrinkled template, an obvious effect on the self-assembly is at the temperature range from 30°C to 50°C. Nematic, curved (mostly are end-to-end) and transition mode can be obtained. According to humidity, GNRs tend to form the nematic fashion in humidity lower than 60%, and the curved fashion in a higher humidity.

Nanoparticles deposition via droplet drying technique generally leads to a coffee-stain-like ring. In the case of different shapes and sizes of nanoparticles, such ring-like deposits also demonstrate various phases within the self-assembly superstructures. For broad spectrum sizes in suspension, size-separation effect has not been considered before. Herein, polydisperse gold anisotropic nanoparticles have been prepared via wet chemical synthesis technique. High-resolution scanning electron microscopy (HRSEM) at various positions of a coffee-stain ring displayed both size-separation and self-assembly of nanoparticles. Especially at the outer edges of a ring-like deposit, side-by-side organized arrays of anisotropic nanoparticles have been observed. Likewise, such ordered arrays generally begin with thin nanorods and the width of nanoparticles increases as one moves inward within such arrays. Also, assembly of deposited arrays is more orderly arranged at the periphery of the ring, whereas such order significantly decreases at the interior region of the ring. Furthermore, it has been observed for a mixture of thick–thin nanorods and spheres that only thick nanorods self-assemble into ordered arrays whereas thin rod-sphere was found disordered everywhere within the ring. Nanoscale interactions are quantified for these systems to understand self-assembly behavior of such anisotropic nanoparticles.

Gold nanoparticles are metallic nanostructures with wide range of applications in biomedicine and biosensing. Among diverse morphologies of gold nanostructures, gold nanorods have attracted much more attention for their outstanding structure, optical property and function. The unique characteristic of these nanostructures encourages their integration with biomolecules of interest for versatile biomedical proposes. In this effort, amyloid fibrils with well-known mechanical strength and chemical stability have been used as biotemplates for assembly of gold nanorods to exploit dual property of both nano and bio counterparts in a hybrid nanoscaffold. To maximize the interaction of the nanostructures with the biotemplate, surface of the gold nanorods was modified with biocompatible polystyrene sulfonate (PSS). Spectroscopic and microscopic techniques including UV–Vis, CD, ThT and TEM were used to characterize formation of insulin amyloid fibrils, gold nanorods and their assemblies on the biotemplate. Morphology of gold nanorods was also monitored upon interaction with amyloid fibrils. Electrochemical impedance spectroscopy of the hybrid nanoscaffold showed that increase in the concentration of the assembled nanostructures on the biotemplate has clearly led to enhancement of conductivity. Results of this investigation highlight gold nanorods as promising candidates in design and fabrication of novel hybrid nanoscaffolds of enhanced conductivity, especially for biosensing and tissue engineering purposes.

The antitumor efficiency of gold nanorod plasmonic photothermal therapy (PPTT) was evaluated experimentally. The rat cholangiocarcinoma line PC-1 was used as a tumor model. Exposure of tumors to 808-nm laser radiation was performed, and the noninvasive temperature monitoring of the tumor tissue was carried out using infrared imager. The growth rate kinetics and morphological alterations of transplanted liver tumors, as well as indicators of lipid peroxidation activity and autointoxication in rat serum, were studied. The activation of lipid peroxidation and the development of autointoxication were detected after PPTT. The results not only demonstrate the antitumor efficacy of the proposed therapeutic technology but also reveal the side effects in the presence of peroxidation products in systemic circulation.

In this paper, we proposed a contrast-enhanced homemade spectral domain optical coherence tomography (SD-OCT) method for monitoring of brain microcirculation. We used the polyethylene glycol (PEG)-ylated gold nanorods (GNRs) as a contrast-enhanced agent, obtained clearly 2D and 3D OCT images of blood vessels and dynamic changes of probes in mouse blood vessels. Owing to high scattering of the PEG-GNRs, more tiny blood vessels can be imaged and the OCT signal can be enhanced by 5.87 dB after injection of PEG-GNRs for 20min, the enhancement then declined gradually for 60min. Our results demonstrate an effective technique for the enhanced imaging of blood vessels in vivo, especially for studies of the brain microcirculation, which could be serviced for disease mechanism research and therapeutic drug monitoring.

Plasmonic nanomaterials are poised to impact the clinical management of cancer through their ability to convert externally applied energy into localized heat at sites of diseased tissue. However, characterization of plasmonic nanomaterials as cancer therapeutics has been limited to xenograft models, creating a need to extend these findings to more clinically relevant models of cancer. Here, we evaluate the method of photothermal ablation therapy in a genetically engineered mouse model (GEMM) of sarcoma, which more accurately recapitulates the human disease in terms of structure and biology than subcutaneous xenograft models. Using polyethylene glycol (PEG)-coated gold nanorods (PEG-NRs), we quantitatively evaluate the ability of nanoparticles to penetrate and accumulate in sarcomas through passive targeting mechanisms. We demonstrate that PEG-NR–mediated photothermal heating results in significant delays in tumor growth with no progression in some instances. Lastly, by evaluating our photothermal ablation protocol in a GEMM, we observe off-target heating effects that are not detectable in xenograft models and which may be of future clinical interest.

Gold nanorods (GNRs) have great potential widespread applications in biomedical imaging, drug delivery and photothermal therapy due to unique surface plasmon resonance (SPR) ranging from visible to near infrared (NIR) region, facile synthesis and easy functionalization. The frequency of SPR is not only determined by the nature of the metal, but also by a number of other parameters, such as particle size and shape, the presence of a capping shell on the particle surface, or the dielectric properties of the surrounding medium. In this study, use is made of finite element method (FEM) for the calculation of the complex effective permittivity of the gold-core nanorod coated with polymer shells. Such a permittivity allows the determination of the absorption spectrum of these clothed nanoparticles. A simple scheme based on FEM is developed, which enables us to compute the optical properties, such as the effective dielectric function and absorption cross-section of coated-GNRs which are embedded in a dielectric matrix. The influences of the aspect ratio, shell thickness and dielectric constant of the shell on the longitudinal and transversal resonances modes are investigated.