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Everywhere in nature we can find wonder designs and systems that never cease to inspire us looking for answers to engineering and design. In this paper, bio-inspired triboelectric nanogenerator (BITENG) has been designed to mimic the motion of kelp, which gently sways along with wave and harness the energy in this process. The energy harvesting has been proven as stable and efficient, which could work under a vibration frequency as low as to 1 Hz. Correspondingly, an output current of about 10 μA and voltage of 260 V can be given by a single unit, which is enough to drive at least 60 LEDs with a power density of 25 μW·cm−2. Furthermore, large scale application can be promoted by connecting such BITENG into network. Such a bio-inspiration provides a new strategy for harvesting wave-energy with promise for new energy sources based on TENGs.

A naphthalimide-based fluorescent probe, Nap-I, with iodoacetamide as the alkylating group, has been synthesized, and its specific fluorescent staining of proteins containing cysteine (Cys) and selenocysteine (Sec) residues in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) has been evaluated. This molecule shows good fluorescence properties in the labeling of protein Cys/Sec residues, while reducing steric hindrance and minimizing changes in the water solubility of proteins. Reaction parameters, such as labeling time and pH, have been investigated, and the optimal labeling conditions for Cys-containing proteins have been determined. Thioredoxin reductase (TXNRD) is best stained at low pH. The probe Nap-I has been successfully used for the quantification of serum proteins and hemoglobin in Tan sheep serum, and TXNRD in Tan sheep liver and muscle has been labeled at low pH. Based on the probe Nap-I, we have also distinguished TXNRD1 and TXNRD2 by SDS-PAGE. The results showed that, compared with the normal microenvironment in which the protein resides, the lower the pH value, the greater the TXNRD activity.

Rose swayed in the breeze are responsible for harnessing the kinetic energy of wind. From a certain perspective, these phenomenon can be utilized to augment plant function to generate electricity with electroactive materials, where triboelectrification happens for producing electricity due to the difference in triboelectric polarity. In this paper, we creatively utilized the triboelectrification on plant organs, which has rarely been studied before, and constructed triboelectric nanogenerators (TENGs) by using rose and Poly (methyl methacrylate) in a contact-separation mode. Under a constant periodical compressive force (100 N) at a frequency of 2 Hz, a maximum open-circuit voltage (Voc) of 30.6 V and short-circuit current (Isc) of 0.78 μA were obtained from a fresh rose petal (3 cm × 3 cm). The maximum output power density could be as high as 27.2 mW/m2 at a resistance of 50 MΩ. Further studies disclosed that these petal surface rich in micro- and nanostructures provided sufficient roughness for hydrophobicity, which means that electrical charges could be generated and the mechanical energy of rain drops could be harvested. Therefore, Isc generated from the petal with falling water droplets on its surface was measured and the peak of Isc was 7.84 nA.

Recent development of interactive motion-tracking and positioning technologies is attracting increasing interests in many areas, such as wearable electronics, intelligent electronics, and the internet of things. For example, the so-called somatosensory technology can afford users strong empathy of immersion and realism due to their consistent interaction with the game. Here, we report a noncontact self-powered positioning and motion-tracking system based on a freestanding triboelectric nanogenerator (TENG). The TENG was fabricated by a nanoengineered surface in the contact-separation mode with the use of a free moving human body (hands or feet) as the trigger. The poly(tetrafluoroethylene) (PTFE) arrays based interactive interface can give an output of 222 V from casual human motions. Different from previous works, this device also responses to a small action at certain heights of 0.01–0.11 m from the device with a sensitivity of about 315 V·m–1, so that the mechanical sensing is possible. Such a distinct...