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A hydrogel‐capped hair‐cell flow microsensor, which closely mimics a superficial neuromast of a fish, is introduced. By encapsulating the hair sensor into the artificial hydrogel cupula a dramatic increase in hair‐sensor sensitivity to the oscillating and the steady flow is achieved. It opens the way toward the remote monitoring of the underwater environment by autonomous, unmanned microvehicles with self‐navigating capability.

We report on the surface behavior of the asymmetric heteroarm poly(ethylene oxide) (PEO)/polystyrene (PS) star polymer on the air−water interface on a solid substrate. These amphiphilic star polymers with different numbers of hydrophobic arms and a similar hydrophilic block differ by architecture (four and three arm molecules, PEO-b-PS3 and PEO-b-PS2), the length of PS chains (molecular weight from about 10 000 up to 24 000), and the number of PS arms (three and two). Detailed analysis revealed that well-developed circular domain surface morphology was formed at the air−water interface. Similar to linear diblock PEO−PS copolymers, the asymmetric heteroarm star polymers at low surface pressure formed circular nanoscale aggregates composed of PS arms. At higher surface pressure, the packing of circular domains became denser, but no clear transition to cylindrical structures was observed in condensed monolayers, contrary to linear block copolymers of similar composition. Therefore, we suggest that for star architecture the formation of highly curved interfaces is heavily favored, domain structure. This surface morphology remained stable even at very high compression close to the monolayer collapse unlike linear diblock copolymers with their tendency for structural reorganization even at very modest compressions.

We found that the amplification of weak multiple interactions between numerous peripheral branches of irregular, flexible, polydisperse, and highly branched molecules can facilitate their self-assembly into nanofibrillar micellar structures at solid surfaces and the formation of perfect long microfibers in the course of crystallization from solution. The core-shell architecture of the amphiphilic dendritic molecules provides exceptional stability of one-dimensional nanofibrillar structures. The critical condition for the formation of the nanofibrillar structures is the presence of both alkyl tails in the outer shell and amine groups in the core/inner shell. The multiple intermolecular hydrogen bonding and polar interactions between flexible cores stabilize these nanofibers and make them robust albeit flexible. This example demonstrates that one-dimensional supramolecular assembling at different spatial scales (both nanofibers and microfibers) can be achieved without a tedious, multistep synthesis of shape-persistent molecules.

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