Jennifer Gracie

Metallic nanoshells heat efficiently on excitation of the localized surface plasmon resonance (LSPR). Whilst investigating the photothermal properties of citrate‐stabilized hollow gold nanoshells (HGNs) synthesized using a sacrificial silver nanoparticle (AgNPs), the LSPR undergoes a distinct blueshift (70 ± 20 nm (0.20 ± 0.06 eV)) when photothermally irradiated. Notably, when functionalized with a Raman reporter, the surface‐enhanced Raman scattering (SERS) signal unexpectedly and dramatically increases 8 ± 2‐fold upon plasmonic heating, despite the LSPR shifting away from the excitation wavelength. This unprecedented enhancement of the SERS signal is absent in samples lacking citrate or prepared using a cobalt nanoparticle template, underscoring the importance of citrate, heat, and AgNPs in eliciting these effects. It is hypothesized that aqueous silver ions near the surface of the HGNs react with the citrate and form a complex that is both light and temperature sensitive. The formation of silver deposits, observed by electron microscopy, alters the core‐to‐shell thickness ratio, resulting in a blueshift in the LSPR, and change the scattering to absorption properties, enabling an improved SERS performance. This new optical phenomenon has now been understood and will be of significant interest to future studies in harnessing the properties of HGNs.

Cucurbiturils (CBs), barrel-shaped macrocyclic molecules, are capable of self-assembling at the surface of nanomaterials in their native state, via their carbonyl-ringed portals. However, the symmetrical two-portal structure typically leads to aggregated nanomaterials. We demonstrate that fluorescent quantum dot (QD) aggregates linked with CBs can be broken-up, retaining CBs adsorbed at their surface, via inclusion of guests in the CB cavity. Simultaneously, the QD surface is modified by a functional tail on the guest, thus the high affinity host-guest binding (logK_a > 9) enables a non-covalent, click-like modification of the nanoparticles in aqueous solution. We achieved excellent modification efficiency in several functional QD conjugates as protein labels. Inclusion of weaker-binding guests (logK_a = 4-6) enables subsequent displacement with stronger binders, realising modular switchable surface chemistries. Our general "hook-and-eye" approach to host-guest chemistry at nanomaterial interfaces will lead to divergent routes for nano-architectures with rich functionalities for theranostics and photonics in aqueous systems.

The maturation of spirit in wooden casks is key to the production of whisky, a hugely popular and valuable product, with the transfer and reaction of molecules from the wooden cask with the alcoholic spirit imparting color and flavor. However, time in the cask adds significant cost to the final product, requiring expensive barrels and decades of careful storage. Thus, many producers are concerned with what "age" means in terms of the chemistry and flavor profiles of whisky. We demonstrate here a colorimetric test for spirit "agedness" based on the formation of gold nanoparticles (NPs) by whisky. Gold salts were reduced by barrel-aged spirit and produce colored gold NPs with distinct optical properties. Information from an extinction profile, such as peak position, growth rate, or profile shape, was analyzed, and our assay output was correlated with measurements of the whisky sample makeup, assays for key functional groups, and spiking experiments to explore the mechanism in more detail. We conclude that age is not just a number, that the chemical fingerprint of key flavor compounds is a useful marker for determining whisky "age", and that our simple reduction assay could assist in defining the aged character of a whisky and become a useful future tool on the warehouse floor.

The immune system plays a crucial role in maintaining a healthy body by working around the clock to recognize and respond to infection. Inflammation is part of the immune system’s protective response to an infection. The inflammatory response is incredibly powerful, so much so that it can damage the body’s cells if it is not tightly controlled. Sometimes, inflammation affects the whole body—this is called sepsis. The powerful and complex mechanisms in place to wipe out the infection can cause serious damage to healthy cells and tissues. Uncontrolled inflammation can cause irreversible damage to the body’s organs, such as the kidneys, eventually causing organs to shut down. If sepsis is not treated rapidly, it can lead to death. In this article, we describe the symptoms and diagnosis of sepsis and some of the current research being performed to better understand this dangerous process.

Targeting tumor necrosis factor-α has proven of considerable value in treatment for rheumatoid arthritis, with substantial benefits achieved in a proportion of treated patients. However, a significant number of patients do not achieve sufficient improvement and as a result there remains considerable unmet clinical need. A number of cytokines have recently been described with proinflammatory activity in rheumatoid arthritis synovitis, including interleukin (IL)-6, IL-12, IL-15, and IL-18. We review recent data that support the notion that some or all of these moieties offer therapeutic potential. The possibility that some may be useful in partial responders to tumor necrosis factor blocking agents or in synergy with the latter is discussed.

Summary. Capacity to produce interleukin‐2 (IL‐2) was measured in haemophiliacs from a well‐defined treated cohort. Patients were selected on the basis of HIV‐1 antibody status, mean annual dose of clotting factor and liver disease severity. T‐cell subsets and peripheral blood mononuclear cell proliferation to Mycobacterium tuberculosis purified protein derivative (PPD) were also measured. Haemophiliacs had reduced IL‐2 production, independent of HIV‐1 antibody status, mean annual dose of clotting factor concentrate used and liver disease severity. In HIV‐1 antibody positive patients reduced levels correlated with PPD proliferative responses (r=0.6, P=0.04) and CD8+ve (r=05, P=0.05) but not CD4 + ve cell numbers (r= 0.3, P=0.2). No such correlations were seen in HIV‐1 antibody negative patients. Reduced IL‐2 production in HIV‐1 antibody negative haemophiliacs was due to a qualitative defect. In HTV‐1 positive patients a qualitative defect in T lymphocytes that selectively proliferate in response to PPD was observed. CD4 + ve cell numbers were reduced in HIV‐1 positive patients.