Review Articles in 2021

Cold chain requirements, distribution challenges and high costs limit the global rollout of many vaccines. This Review discusses plant molecular farming in combination with advanced materials strategies as a new platform for the local production of thermostable vaccines and other biologics.

The central nervous system is protected by tightly regulated physiological barriers, which make drug delivery into the brain and spinal cord very challenging. This Review discusses the pathophysiological changes that complicate drug delivery into the central nervous system and examines materials-based strategies to bypass or overcome these barriers for drug delivery.

Spin–orbit coupling can be leveraged to enable new functional properties in oxide materials, in particular, for spintronics applications. This Review surveys significant recent advances in the field of oxide spin-orbitronics and discusses its future perspectives.

Organelles are compartments inside cells that play important parts in intercellular and intracellular communication, reflecting the metabolic state of the cell. This Review discusses biological pathways that can be exploited to target cargo to specific organelles in vivo, highlighting nucleic acids as suitable delivery vehicles for organelle-level imaging, diagnosis and therapy.

Soft actuators are flexible and compliant and thus perfectly suited to interact with the human body. This Review discusses tethered, untethered and biohybrid soft actuation strategies, highlights promising real-world applications of soft robots and identifies key future challenges, such as implementing physical intelligence and end-of-life strategies.

Solution-processed networks of 2D materials are promising for applications in printed electronics. This Review examines how these networks are often electrically limited by the junctions between nanosheets, a phenomenon rarely reported and poorly understood, and surveys the macroscopic electrical properties of printed 2D networks, with a focus on inter-sheet junctions.

Solid-state materials have emerged as a platform for probing and manipulating topological phases of matter. This Review surveys topological materials discovery in nonmagnetic crystalline solids, focusing on the role of crystal symmetry and geometry in topological material predictions.

Sex-related differences in health and disease are often overlooked in tissue engineering. This Review discusses sex-based differences in the (patho)physiology of the cardiovascular system, providing a design framework for sex-specific cardiac tissue models and an outlook to developing sex-specific in vitro models in general.

The materials community must address the greenhouse gas emissions burden of materials production. This Review assesses the potential for decarbonization of the cement, metals and petrochemical industries, revealing opportunities to strengthen the connections across industries and length scales — from the atomic scale through to materials markets — to meet climate targets.

Plastic debris continues to contaminate the environment, negatively impacting wildlife and ecosystems. This Review argues that polymer selection and product design must incorporate strategies for end-of-life management and strive to eliminate, or at least minimize, environmental persistence of plastic materials.

Ferroelectric domain walls hold great potential as multifunctional 2D systems for next-generation nanotechnology. This Review discusses recent advances in the field and new strategies for developing the domain walls into ultra-small electronic components.

The immune response to a vaccine is characterized by a complex time-dependent interplay between various cell types and molecules in different tissues in our body. This Review explores materials-based strategies for the spatial and temporal control of the mechanisms that underlie vaccine immune responses.

The integration and function of implanted biomaterials and devices depend on the responses of the host tissue, such as macrophage activation and neovascularization. This Review discusses how intravital microscopy can be applied to assess the mechanisms underlying regenerative and pathological responses to implants.

Bio-based polymers that exhibit superior performance relative to petroleum-based incumbents can encourage industry adoption and offset fossil carbon use. This Review introduces performance-advantaged, bio-based polymers and highlights examples wherein superior performance is facilitated by the inherent chemical functionality of bio-based feedstocks.

Superconducting qubits hold great promise for quantum computing, and recently there have been dramatic improvements in both coherence times and the power of quantum processors. This Review explores how the path forward involves balancing circuit complexity and materials perfection, eliminating defects while designing qubits with engineered noise resilience.

The CO₂ reduction reaction can be used to produce carbon-neutral chemicals using renewable electricity. This Review presents material design strategies for controlling the transport of products and reactants in electrochemical reactors that convert CO₂ emissions into chemicals and fuels.

The development of antibiotic tolerance and resistance has demanded the search for alternative antibacterial therapies. This Review discusses antibacterial biomaterials and biomaterial-assisted delivery of non-antibiotic therapeutics for the treatment of bacterial infectious diseases, with a focus on clinical translation.

Low-nuclearity catalysts incorporating supported metal atoms or small clusters on appropriately tailored carriers are growing in diversity and have great potential in catalysis. This Review examines progress in their synthesis and characterization towards the atomically precise design of high-performing new architectures.

Liquid crystalline elastomers are stimuli-responsive polymeric materials whose mechanical properties can be programmed by patterning their local orientation, making them promising candidates to serve as low-density actuators and functional elements in various applications. This Review discusses the synthesis and processing of liquid crystalline elastomers, with a focus on alignment methods and potential applications.

Engineered living materials are composed of a matrix that encapsulates living cells, which endow the biomaterial with controllable responses and dynamic functions. This Review discusses the fabrication and biomedical applications of engineered living materials that contain microorganisms as the living, active component.