Untethered small actuators have various applications in multiple fields. However, existing small-scale actuators are very limited in their intractability with their surroundings, respond to only a single type of stimulus and are unable to achieve programmable structural changes under different stimuli. Here, we present a multiresponsive patternable actuator that can respond to humidity, temperature and light, via programmable structural changes. This capability is uniquely achieved by a fast and facile method that was used to fabricate a smart actuator with precise patterning on a graphene oxide film by hydrogel microstamping. The programmable actuator can mimic the claw of a hawk to grab a block, crawl like an inchworm, and twine around and grab the rachis of a flower based on their geometry. Similar to the large- and small-scale robots that are used to study locomotion mechanics, these small-scale actuators can be employed to study movement and biological and living organisms.

The frequent outbreak of global infectious diseases has prompted the development of rapid and effective diagnostic tools for the early screening of potential patients in point-of-care testing scenarios. With advances in mobile computing power and microfluidic technology, the smartphone-based mobile health platform has drawn significant attention from researchers developing point-of-care testing devices that integrate microfluidic optical detection with artificial intelligence analysis. In this article, we summarize recent progress in these mobile health platforms, including the aspects of microfluidic chips, imaging modalities, supporting components, and the development of software algorithms. We document the application of mobile health platforms in terms of the detection objects, including molecules, viruses, cells, and parasites. Finally, we discuss the prospects for future development of mobile health platforms.

Promoted therapeutic angiogenesis is a major objective in the area of regenerative medicine, and sufficient vascularization of artificial tissues or organs is one of the main difficulties for the realization of tissue engineering methods. The identification of new kinds of pro-angiogenic materials will greatly profit developments in regenerative medicine. The use of exosomes for this intention is a considerably new idea developed in recent years. However, several limitations need to be addressed before their use as clinical therapeutics, including the lack of efficient exosome enrichment and methods to endow exosomes with targeting ability. Herein, we pioneered biomimetic particles with topographic structures for exosome isolation. Using this system, nearly 80% of exosomes were isolated in 30 min. Through a donor cell-assisted membrane modification strategy, the isolated exosomes exhibited increased targeting to blood vessels due to the modified Arg-Gly-Asp (RGD) peptide on the exosome membrane, and simultaneously possessed a synergistic therapeutic angiogenesis effect and angiogenesis imaging attributed to metabolic labeling by click chemistry both in vitro and in vivo. The engineered exosomes represent a potential new therapeutic tool for angiogenesis therapy and imaging in a bio-friendly manner.