Volume 16 Issue 11, November 2021

The halide perovskite family has, arguably, become today’s most promising emerging materials sets for optoelectronic applications. Here, we discuss the underperformance to date of the colloidal nanocrystal forms of these materials when employed in electroluminescent lighting devices relative to their counterparts, in which the emitter layer is in the form of polycrystalline films. However, we highlight the bright future of halide perovskite colloidal nanocrystals in light-emission technologies such as LCD displays, quantum light sources and even alternative LED configurations, as well as key guidelines for their further development to get there.

Polyethylene glycol, used as a stabilizer in nanomedicine formulations, has recently been indicated as the possible cause of the anaphylactic reactions against the COVID-19 mRNA-based vaccines, but the evidence supporting this is contradictory, and other factors might be involved.

A common understanding of the key regulatory term “substance” is needed for the implementation of chemicals regulations for nanomaterials.

Transport measurements through a single molecule unveil the mechanism of the catalytic Suzuki–Miyaura cross-coupling reaction.

A leaky DNA origami plug stops protein flow through a nanopore.

Nanoparticles used for biomedical applications might elicit unexpected adverse or beneficial biological effects unrelated to the function for which they were designed. In this Review, the authors describe some of these ‘yin and yang’ ancillary effects, and discuss their implications for nanomedicine development.

Spatiotemporal thermoelectric microscopy enables the observation of electronic heat flow in graphene in diffusive and hydrodynamic regimes at room temperature, as well as a controlled transition from a Fermi liquid to Dirac fluid.

Unidirectional alignment of MoS₂ domains during epitaxial growth on C/A sapphire enables the realization of large-area MoS₂ single crystals.

Moiré trions are observed in electrostatically gated WSe₂/MoSe₂ heterobilayers, where photoluminescence polarization switching reveals a competition between valley-flip and spin-flip relaxation pathways of photo-excited carriers during trion formation.

Although conventional analytical techniques can measure ensemble averages, single-molecule junctions can sense molecular reaction processes at the single-event level. The integration of a single-molecule Pd catalyst into a gapped graphene junction enables the electrical detection of a full catalytic cycle of the Suzuki–Miyaura coupling and clarifies the controversial transmetallation mechanism.

High optical-quality-factor, non-local metasurfaces enable independent functions across different wavelength bands.

Low-temperature ultraclean integration of large-area MoS₂ thin-film transistors with nitride micro-LEDs through a back end of line process enables the demonstration of displays with high resolution and uniformity.

Moiré-trapped interlayer excitons in a transition metal dichalcogenide heterobilayer serve as a sensitive optical probe of carrier filling in their immediate environment to characterize the doping of the moiré superlattice.

A trap, formed by a DNA-origami sphere docked onto a solid-state nanopore, allows the hydrodynamic trapping and label-free observation of single proteins, enabling nucleotide-dependent protein conformation to be discriminated on the timescale of submilliseconds to hours.

Tumours that grow on organ surfaces are difficult to eradicate as the complex topology of underlying tissues might hamper accessibility to tumour foci even after surgery. In this paper the authors engineer a peptide-based hydrogel that can be applied on surface tumours before or after resection, conform to the tissue underneath and release therapeutics.

The stimulation of interferon genes (STING) pathway with STING agonists such as cyclic dinucleotides (CDNs) has emerged as a promising immunotherapeutic approach. Here, the authors show that Mn²⁺ can amplify the STING-promoted anti-tumour immune response in challenging murine tumour models by coordinating with CDNs and self-assembling into nanoparticles that can be delivered locally and systemically.

Type I interferons (IFNs) have strong antitumour activity yet their clinical use is limited by their off-target toxicity and by their effect on immune evasion. Here the authors design a biomimetic nanoparticle loaded with an IFN inducer, which can at the same time replenish intratumoural IFNs and reduce their immunosuppressive activity, showing therapeutic efficacy in several animal tumour models.

Nanoparticle-mediated photoporation is used to temporarily permeabilize cell membranes for intracellular delivery of macromolecules, but cell exposure to nanoparticles might cause cellular damage and hamper application of the technique to therapeutic cell engineering. Here the authors show that, under photothermal heating, nanofibre-embedded iron oxide nanoparticles can be used to deliver effector macromolecules to different types of cells, in a contactless manner, with no cellular toxicity or diminished therapeutic potency.