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Chitosan-based thermosensitive hydrogels have been widely used in drug delivery and tissue engineering, but their poor bioactivity has limited their further applications. Integral active oyster peptide microspheres (OPM) with an average particle diameter of 3.9 μm were prepared with high encapsulation efficiency (72.8%) and loading capacity (11.9%), exhibiting desirable sustained release effects. Using catechol functionalized chitosan (CS-C) as the polymeric matrix, OPM as the filler, and β-sodium glycerophosphate (β-GP) as a thermal sensitizer, the thermosensitive hydrogel CS-C/OPM/β-GP was prepared. Besides, the application of the hydrogel on wound healing was studied, and its biosafety was evaluated. The results of cell migration in vitro showed that the cell migration rate of CS-C/OPM/β-GP reached 97.47 ± 5.41% within 48 h, indicating that the hydrogel accelerated the migration of L929 cells. As demonstrated in the mouse skin wound experiment, CS-C/OPM/β-GP hydrogel not only inhibited the aggregation of diversified inflammatory cells and accelerated the generation of collagen fibers and new blood vessels of the wound, but also enhanced the synthesis of total protein (TP) in granulation tissue, and up-regulated the expression of Ki-67 and VEGF in the injury, thereby achieving fast wound healing. Safety evaluation results showed that CS-C/OPM/β-GP hydrogel was not cytotoxic to L929 cells, and the hemolysis ratio was less than 5% within 1 mg/mL. In conclusion, CS-C/OPM/β-GP hydrogel is expected as a promising medical dressing for wound healing.

Finger mobility plays a crucial role in everyday lives and is especially a leading indicator during hand rehabilitation and assistance tasks. In this study, a soft sensor-based three-dimensional (3-D) finger motion measurement system is proposed. Specifically, we report the use of a soft rope-embedded microfluidic sensor with high sensitivity and responsivity for strain sensing in the proposed system. These microfluidic strain sensors are proved to have the advantages of being easy to fabricate, chemically inert, with low hysteresis and good flexibility in their output signals. Besides, kinematic modeling of different finger joints are also provided to investigate the reasonable sensor locations for obtaining accurate measurements. Algorithms to identify the varied non-coplanar motions (abduction/adduction and flexion/extension joint angles) are presented by means of tracking the locations of the first metacarpal bone in multiple thumb postures. As a demonstration of their potential, the rope-embedded strain sensing units were used as curvature sensors mounted on the dorsum of target joints. The soft sensor-based 3-D finger motion measurement system and algorithms are experimentally verified by comparison with a camera-based motion capture device. Placing sensors at the optimal locations, joint angle measurement can reach up

Long-term excessive alcohol intake can easily lead to gastritis, gastric ulcer, and gastric bleeding. In this paper, the gastric acid-responsive hydrogel of CS-NAC/alginate/tilapia collagen peptide (CS-NAC/ALG/TCP) was developed. Its structure and properties were determined. The alcohol-induced gastric mucosal injury models in mice were established to evaluate the protective effects of CS-NAC/ALG/TCP. The results showed that CS-NAC/ALG/TCP was successfully fabricated, and it showed a sustained release of TCP, strong mucoadhesion, and excellent biodegradability in vitro. In the animal experiments, CS-NAC/ALG/TCP improved the oxidative stress status of the gastric mucosa by increasing the levels of SOD, GSH, and CAT in tissues. It also down-regulated the expression of MPO, TNF-α, IL-1β, and IL-6, and increased the production of gastric protective factors such as PGE2 and NO in mouse stomach, thereby reducing the alcohol-induced inflammation and protecting the gastric mucosal injury. Besides, CS-NAC/ALG/TCP can also increase the activities of alcohol metabolism enzymes to improve alcohol metabolism, thereby reducing alcoholic damage. In conclusion, CS-NAC/ALG/TCP is a promising candidate for the treatment of alcohol-induced gastric injury.

Lung metastasis is a primary obstacle in the clinical treatment of metastatic breast cancer. Most patients with lung metastasis eventually die of recurrence. Recurrence may be related to self-seeding, which occurs when circulating tumor cells re-seed into the tumors they originated from (metastasis or carcinoma in situ). Tumor-derived exosomes have been intensively revealed to promote the progression of various cancers. However, whether tumor-derived exosomes play roles in tumor self-seeding has not yet been identified. By establishing a self-seeding nude mouse model, we found that exosomes derived from MDA231-LM2 cells (subpopulations of breast cancer lung metastasis) potentiate the growth of MDA-MB-231 xenografts. More importantly, laser confocal microscopy and flow cytometry results identified that MDA231-LM2-secreted exosomes promote the seeding of MDA231-LM2 cells into MDA-MB-231 xenografts. These findings suggest MDA231-LM2-secreted exosomes as a promising target to treat breast cancer lung metastasis.

Anodic TiO2 nanotube arrays (ATNAs) have been one of the promising electrode materials for supercapacitors due to good chemical stability, large surface area and simple fabrication method. However, the specific capacitance of ATNAs is generally low. Here, we focus on the hydrothermal treatments of ATNAs in (NH4)2TiF6 dilute solutions. After the (NH4)2TiF6 hydrothermal treatments, the smooth wall of ATNAs became rough, a layer of nanoparticles were generated on the surface of nanotubes concurrently. The specific capacitance of the hydrothermally treated ATNAs increased remarkably due to the special nanostructure composed of rough tube walls and the nanoparticles embedded on the tube walls. After the hydrothermal treatment in 0.01 M (NH4)2TiF6 aqueous solution at 120 °C for 45 min, the ATNAs exhibit a specific capacitance of 31.12 mF cm−2, about a 3.1-fold improvement over the untreated ones.

Special nanostructures of porous anodic alumina (PAA), such as the petal-like micropattern and nanofibers of alumina, cannot be explained by the classical field-assisted dissolution and dynamic equilibrium models. Here, by combination of oxygen bubble mould and plastic flow model, a reasonable explanation for these special nanostructures is proposed. The petal-like micropatterns of PAA and nanofibers of alumina are all clarified by the oxygen bubble mould and the plastic flow model. The self-ordering nanochannels of PAA are attributed to the oxide plastic flow around a gas bubble mould at each pore bottom. The petal-like micropatterns and nanofibers of alumina are attributed to chemical corrosion enhanced by the micro-gas-flow and micro-liquid-flow.

At present, very few soft actuators have achieved strain and pressure sensing capabilities simultaneously. In this paper, one kind of soft strain and pressure sensors based on liquid conductive metal (EGaIn) are proposed, which can be integrated into typical soft pneumatic actuator easily for sensing functions. Here we report design models, fabrication techniques, sensing characterization and sensation experiments for the potential sensors. Especially for EGaIn-based strain sensors, sensitivity is improved greatly (up to 28.6–~30.8) realized via embedded fibers, and low hysteresis (2.23%) and high repeatability (loading: ±0.92% and unloading: ±1.34%) are further demonstrated. Also, we explore a novel embedded channels-manufacturing method called lost-wax casting, which could overcome fabrication complexity, possible leakage and low manufacturing success rate dramatically. Finally, our experimental demonstration utilized the sensorized actuators to detect the profiles, sizes and softness of objects and obtained desired results like a real finger.