There is an increasing interest to develop a next generation of touch pads that require stretchability and biocompatibility to allow their integration with a human body, and even to mimic the self‐healing behavior with fast functionality recovery upon damage. However, most touch pads are developed based on stiff and brittle electrodes with the lack of the important nature of self‐healing. Polyzwitterion–clay nanocomposite hydrogels as a soft, stretchable, and transparent ionic conductor with transmittance of 98.8% and fracture strain beyond 1500% are developed, which can be used as a self‐healing human–machine interactive touch pad with pressure‐sensitive adhesiveness on target substrates. A surface‐capacitive touch system is adopted to sense a touched position. Finger positions are perceived during both point‐by‐point touch and continuous moving. Hydrogel touch pads are adhered to curved or flat insulators, with the high‐resolution and self‐healable input functions demonstrated by drawing, writing, and playing electronic games.

The improper handling of decrypted information can lead to the leakage of confidential data. Thus, there is increasing interest in the development of self‐erasing decrypted data. Herein, we report a urease‐containing fluorescent hydrogel for multistage information security protection. Information can be input into the fluorescent hydrogel, which is based on the protonated 4‐(N,N‐dimethylaminoethylene) amino‐N‐allyl‐1,8‐naphthalimide (DEAN‐H+) and doped with urease, using metal ions, such as Zn2+ that coordinate with DEAN. Upon exposure to urea, urease produces NH3, which reduces the fluorescence of the hydrogel. In the presence of urea, metal‐coordinated hydrogel fluorescence decreases more slowly than the fluorescence of the hydrogel alone, revealing the information. The displayed information is then automatically erased within a few minutes. This work opens up a new insights in designing and fabricating information storage materials.

Amine-based cationic polymers have been extensively explored as nonviral carriers for gene delivery, but inefficient intracellular unpacking of polymer/ DNA complexes (polyplexes) to release plasmids is still a key limiting step to high transfection efficiency. Furthermore, the amine-resulting cationic charges in the polymer chains, and even their degraded fragments, inherently interfere with transgene expression. A cationic polymer capable of converting to uncharged fragments once inside cells would not only quickly release the DNA, but also not interfere with the gene transcription process for efficient gene expression and low toxicity. A new class of polysulfoniums that can degrade into neutral thioether fragments triggered by reactive oxygen species (ROS) is reported. The polysulfoniums condense DNA into nanosized polyplexes, which can be quickly internalized and efficiently escape from endo/lysosomes. In cancer cells, the oxidation of the boronic acid/ester by the elevated ROS levels triggers polysulfonium to break down into neutral thioether fragments, efficiently releasing DNA for gene expression. More importantly, the polyplexes have excellent serum resistance; in vivo, they efficiently deliver the suicide gene pTRAIL to intraperitoneal tumors eliciting effective anticancer activity.