Nature nanotechnology最新文献

The success of personalized cancer immunotherapy depends on the initial tumour antigenic presentation to dendritic cells and macrophages. Tumour-derived extracellular vesicles (TEVs) contain abundant tumour antigenic molecules. The presence of anti-phagocytotic signals such as cluster of differentiation 47 (CD47) on the surface of the TEVs, however, leads to evasion of the same dendritic cells and macrophages. Here we show that iron oxide hydroxide nanocomposites can successfully mask TEV surfaces and unblock phagocytosis without affecting extracellular vesicles’ elicited immune goals. After internalization, the mask disintegrates in the lysosome, releasing the tumour antigenic cargo. This triggers antigen presentation and promotes dendritic cell activation and maturation and macrophage reprogramming in animal models, leading to a drastic reduction of tumour volume and metastasis, and in human malignant pleural effusion clinical samples. This straightforward masking strategy eliminates the ubiquitous anti-phagocytosis block found in clinical samples and can be applied universally across all patient-specific TEVs as tumour antigenic agents for enhanced immunotherapy.

Electronic systems and devices operating at significant power levels demand sophisticated solutions for heat dissipation. Although materials with high thermal conductivity hold promise for exceptional thermal transport across nano- and microscale interfaces under ideal conditions, their performance often falls short by several orders of magnitude in the complex thermal interfaces typical of real-world applications. This study introduces mechanochemistry-mediated colloidal liquid metals composed of Galinstan and aluminium nitride to bridge the practice–theory disparity. These colloids demonstrate thermal resistances of between 0.42 and 0.86 mm² K W⁻¹ within actual thermal interfaces, outperforming leading thermal conductors by over an order of magnitude. This superior performance is attributed to the gradient heterointerface with efficient thermal transport across liquid–solid interfaces and the notable colloidal thixotropy. In practical devices, experimental results demonstrate their capacity to extract 2,760 W of heat from a 16 cm² thermal source when coupled with microchannel cooling, and can facilitate a 65% reduction in pump electricity consumption. This advancement in thermal interface technology offers a promising solution for efficient and sustainable cooling of devices operating at kilowatt levels.

Electrical current pulses can be used to manipulate magnetization efficiently via spin–orbit torques. Pulse durations as short as a few picoseconds have been used to switch the magnetization of ferromagnetic films, reaching the terahertz regime. However, little is known about the reversal mechanisms and energy requirements in the ultrafast switching regime. In this work we quantify the energy cost for magnetization reversal over seven orders of magnitude in pulse duration, in both ferromagnetic and ferrimagnetic samples, bridging quasi-static spintronics and femtomagnetism. To this end, we develop a method to stretch picosecond pulses generated by a photoconductive switch by an order of magnitude. Thereby we can create current pulses from picoseconds to durations approaching the pulse width available with commercial instruments. We show that the energy cost for spin–orbit torque switching decreases by more than an order of magnitude in all samples when the pulse duration enters the picosecond range. We project an energy cost of 9 fJ for a 100 × 100 nm² ferrimagnetic device. Micromagnetic and macrospin simulations unveil a transition from a non-coherent to a coherent magnetization reversal with a strong modification of the magnetization dynamical trajectories as pulse duration is reduced. Our results show the potential for high-speed magnetic spin–orbit torque memories and highlight alternative magnetization reversal pathways at fast timescales.