This month in pictures

Stimulus‐responsive polymers are attractive for microactuators as they can be easily miniaturized and remotely controlled for untethered operation. This SEM image shows a single magnetic cilium prepared through magnetic-assisted self-assembly, and used to create elastomers with programmable shapes to advance soft materials and robotic devices.

Accurately diagnosing cancer and identifying its stage of development is crucial for saving lives. Carcinomas that are likely to spread show a number of distinct characteristics that are detectable through force spectroscopy. These results could help improve the prognosis in epithelial cancers with metastasis risk.

This image shows polycrystaline structures of isotactic polypropylene (iPP) seen through a polarized optical microscope during crystallization at 130 °C. iPP crystals were used as a model for investigating the effects semicrystalline polymers have on light scattering.

What at first glance look like rings in this TEM image are in fact gold nanoparticles on poly(lactic-co-glycolic acid) (PLGA) spheres. The PLGA spheres are not easily visible, and so the darker gold nanoparticles on the PLGA surface appear to be forming into clusters of rings. Aesthetics aside, the purpose of these PLGA-Au co-assemblies is to enhance photoacoustic imaging and photothermal therapy in treating cancer.

This scanning electron microscopy image shows microchannels fabricated by two-photon polymerization, which were then used to mold 3D liquid crystal network microstructures. These microchannels were designed using a “pixelated” technique with equally spaced, 10 μm × 10 μm pixels. This technique enables the fabrication of a variety of channel patterns, allowing more freedom when designing liquid crystal network microstructures.

This spheroidally shaped cell culture of human embryonic kidney cells was templated by a photochemical technique. Photochemistry was used to controllably create hollow shapes within hydrogel structures. These hollows were then seeded with cells, which grew to fill the empty space. The spheroids were stained using a cell marker and the 3D imaging was accomplished with a bespoke digital micromirror-device-based confocal microscope.

Zwitterionic polymers allow researchers to fabricate drug-carrying microrobots that can operate covertly under the immune system’s radar. SThese sneaky bots were made using fully zwitterionic photosensitive materials developed for two‐photon polymerization and 3D microprinting.