Amino acids and short peptides modified with the 9-fluorenylmethyloxycarbonyl (Fmoc) group possess eminent self-assembly features and show distinct potential for applications due to the inherent hydrophobicity and aromaticity of the Fmoc moiety which can promote the association of building blocks. Given the extensive study and numerous publications in this field, it is necessary to summarize the recent progress concerning these important bio-inspired building blocks. Therefore, in this review, we explore the self-organization of this class of functional molecules from three aspects, i.e., Fmoc-modified individual amino acids, Fmoc-modified di- and tripeptides, and Fmoc-modified tetra- and pentapeptides. The relevant properties and applications related to cell cultivation, bio-templating, optical, drug delivery, catalytic, therapeutic and antibiotic properties are subsequently summarized. Finally, some existing questions impeding the development of Fmoc-modified simple biomolecules are discussed, and corresponding strategies and outlooks are suggested.

Peptide-based semiconductors: For semiconductors, one often thinks of inorganic materials, such as doped silicon, or aromatic organic polymers and small molecules. Tao et al. review progress in making semiconductors based on self-assembling short peptides. The structures that form show extensive π and hydrogen bonding leading to a range of semiconductor properties, which can be tuned through doping or functionalization of the peptide sequences. These materials may shed light on biological semiconductors or provide an alternative for constructing biocompatible and therapeutic materials. Science , this issue p. aam9756

Stretchability and self-healing ability are essential attributes of modern electronic sensors for wearable applications. Herein, intrinsically ultrastretchable, self-healing and transparent humidity sensors composed of ionic κ-carrageenan/polyacrylamide (PAM) double network (DN) organohydrogels are fabricated via a facile solvent-exchange strategy. Hygroscopic ethylene glycol (EG) and glycerol (Gly) are introduced in the organohydrogels to promote both anti-drying and humidity sensing capabilities. The organohydrogel sensors display unprecedented stretchability (1225% strain) and excellent sensing performance, including fast response (0.27 s) and recovery time (0.3 s), wide relative humidity (RH) detection range (4–90%), stability and linearity. The conductance of Gly-DN sensors increases more than 543 times with increasing RH from 4% to 90%. With sufficient sensitivity, the humidity sensors can monitor human respiration with stable and repeatable output. The enhanced sensitivity and moisture-holding ability are attributed to the ready formation of hydrogen bonds between water molecules and enormous hydrophilic groups, including –OH, SO₃ ⁻ and –NH₂, in the elaborate polymer networks and binary solvent. The hindering effect of polymer chains on the transport of conductive ions plays a key role in producing a transducing signal, which is proposed as the mechanism of the novel sensors.

Rapid advances in wearable electronics and mechno‐sensational human–machine interfaces impose great challenges in developing flexible and deformable tactile sensors with high efficiency, ultra‐sensitivity, environment‐tolerance, and self‐sustainability. Herein, a tactile hydrogel sensor (THS) based on micro‐pyramid‐patterned double‐network (DN) ionic organohydrogels to detect subtle pressure changes by measuring the variations of triboelectric output signal without an external power supply is reported. By the first time of pyramidal‐patterned hydrogel fabrication method and laminated polydimethylsiloxane (PDMS) encapsulation process, the self‐powered THS shows the advantages of remarkable flexibility, good transparency (≈85%), and excellent sensing performance, including extraordinary sensitivity (45.97 mV Pa⁻¹), fast response (≈20 ms), very low limit of detection (50 Pa) as well as good stability (36 000 cycles). Moreover, with the LiBr immersion treatment method, the THS possesses excellent long‐term hyper anti‐freezing and anti‐dehydrating properties, broad environmental tolerance (−20 to 60 °C), and instantaneous peak power density of 20 µW cm⁻², providing reliable contact outputs with different materials and detecting very slight human motions. By integrating the signal acquisition/process circuit, the THS with excellent self‐power sensing ability is utilized as a switching button to control electric appliances and robotic hands by simulating human finger gestures, offering its great potentials for wearable and multi‐functional electronic applications.