This PrimeView highlights the therapeutic and diagnostic applications of extracellular vesicle analysis, which are fueled by fundamental biological insights into their biogenesis, composition, release and uptake.

This PrimeView highlights how inductively coupled plasma mass spectrometry can be used for quantitative analysis of major, minor and trace elements or isotopes.

This PrimeView highlights the various applications of upcycled chlorinated plastics with added value and versatility.

This PrimeView highlights best practices for shell isolated nanoparticle enhanced Raman spectroscopy, with a focus on factors that can affect the workflow.

This PrimeView highlights the use of droplet-based microfluidics systems in chemical, biological and materials research.

This PrimeView highlights the considerations for commercializing nanomaterials as contrast agents.

Logic diagrams are employed in electrical engineering for visualizing switching circuits. However, their utility and applicability extend far beyond the technical sciences. Here, we argue that natural and social scientists alike should consider using logic diagrams in their research. For certain analytical problems, logic diagrams are a perfect fit.

This PrimeView highlights the use of extended reality techniques across a range of biomedical research applications, including data visualization and training.

This PrimeView highlights the use of different twin study designs in behavioural genetics research to probe causal pathways.

This PrimeView highlights how the diverse properties of covalent organic frameworks can be used for a range of applications

This PrimeView highlights the trade-off between biological complexity and tunability when designing and fabricating hydrogels for use in mechanobiology.

Data analysis relies heavily on computation, and algorithms have grown more demanding in terms of hardware and energy. Monitoring their environmental impacts is and will continue to be an essential part of sustainable research. Here, we provide guidance on how to do so accurately and with limited overheads.

This PrimeView highlights ways to achieve spatial and temporal control in integrated catalysis.

This PrimeView highlights chemical reactions that can be improved by using nanostructure-based surface plasmons to create milder conditions.

This PrimeView highlights how to access the terahertz band in a time-domain experiment.

This PrimeView highlights the techniques involved in light-based vat-polymerization bioprinting, including two-photon lithography, digital light processing and volumetric additive manufacturing.

This PrimeView highlights how triboelectric nanogenerators can be used to harvest energy from the natural environment.

New nanomaterials are being developed for efficient biomolecule delivery to plants. However, detection and quantification of plant cell entry are challenging and currently rely on subjective methods that lack proper controls. The necessary considerations of performing nanoparticle-mediated delivery in plants and how to accurately quantify delivery efficiency are discussed.

This PrimeView highlights the peptidomics workflow for sampling, analyzing and characterizing peptides.

Applying a high voltage to a liquid passing through a capillary disintegrates the liquid meniscus to generate a fine spray of charged droplets. As the droplets evaporate, polar molecules dissolved in the liquid are ionized and brought into the gas phase. This phenomenon is commonly known as electrospray ionization (ESI). The gaseous ions can be analysed using mass spectrometry (MS) to determine their molecular masses and chemical structures. Polar analytes — including low-molecular-weight species such as amino acids, peptides, nucleotides and synthetic chemicals; macromolecules, for example, synthetic and natural polymers; and nanoscale particles, for instance, viruses — are ionizable using ESI. In the past three decades, ESI-MS has evolved into a powerful instrumental approach useful to (bio)chemists in a wide range of applications. Several different variants have been developed to extend its functionality. For obtaining chemical and structural information on macromolecules, ESI-MS is complementary to fluorescence spectroscopy, nuclear magnetic resonance spectroscopy, X-ray crystallography and cryo-electron microscopy. This Primer discusses the ESI setup, mechanism and variants. It further introduces sample and instrument-related factors that affect the ionization process, applications and current research, as well as giving a future perspective.