Premature drug release is a common drawback in stimuli-responsive drug delivery systems (DDS), especially if it depends on internal triggers, which are hard to control, or a single external stimulus, which can only have one function. Thus, many DDS systems have been reported that combined different triggers; however, limited success has been established in fine-tuning the release process, mainly due to the poor bioavailability and complexity of the reported designs. This paper reports the design of a hybrid microcapsule (h-MC) by a simple layer-by-layer technique comprising polysaccharides (sodium alginate, chitosan, and hyaluronic acid), iron oxide, and graphene oxide (GO). Electrostatic assembly of the oppositely charged polysaccharides and graphene sheets provided a robust structure in which to load drugs through pH control. The polysaccharide component ensured high biocompatibility, bioavailability, and tumor cells targeting. The alternative magnetic field and near-infrared laser triggerable Fe3O4@GO component provided for dual high-energy and high-penetration hyperthermia therapy. On-demand drug release from h-MC can be achieved by synchronizing these external triggers, making the release highly controllable. The synergistic effect of hyperthermia and chemotherapy was successfully confirmed in vitro and in vivo.

Thread/fabric-based microfluidic device for sweat sensing and monitoring.

At present, the pollution of microplastic directly threatens ecology, food safety and even human health. Polyethylene terephthalate (PET) is one of the most common of microplastics. In this study, the micro-size PET particles were employed as analog of microplastic. The engineered strain, which can growth with PET as sole carbon source, was used as biocatalyst for biodegradation of PET particles. A combinatorial processing based on whole-cell biocatalysts was constructed for biodegradation of PET. Compared with enzymes, the products can be used by strain growth and do not accumulated in culture solution. Thus, feedback inhibition of products can be avoided. When PET was treated with the alkaline strain under high pH conditions, the product concentration was higher and the size of PET particles decreased dramatically than that of the biocatalyst under neutral conditions. This shows that the method of combined processing of alkali and organisms is more efficient for biodegradation of PET. The novel approach of combinatorial processing of PET based on whole-cell biocatalysis provides an attractive avenue for the biodegradation of micplastics.

According to the sensing mechanism, pressure sensors can be divided into five types: piezoelectric, [1,2] piezoelectric resistivity, [3][4][5][6] capacitance, [7,8] triboelectric, [9,10] and transistor. [11] Piezoresistive sensors have attracted much attention in recent years due to their simple design, low manufacturing cost, good signal repeatability, low power consumption, low working voltage, and simple measurement scheme. [12][13][14][15][16][17][18] The elastic pressure sensor is usually composed of sensing material, substrate material, and electrode. The sensing material can be filled or coated on the substrate material to activate the conductive path. Under the external pressure, the contact area between the surface conductive elements increases significantly, resulting in a significant decrease in the path resistance or contact resistance. The change of resistance is due to the deformation of the microstructure under pressure, which leads to the change of the contact area. The traditional rigid material pressure sensor has been eliminated due to its poor reliability and low applicability. As an optional piezoresistive material, nanomaterials have been proved to be potential components of novel strain sensors with enhanced performance. High-performance sensor devices based on several typical nanostructures, such as carbon nanotubes [19,20] and graphene, have been developed. [21] However, the sensors based on these materials have some defects, such as complex manufacturing processes and unknown toxicity.Sensing material is the essential component of a pressure sensor. In terms of sensing materials, metal nanomaterials, as one of the most popular multifunctional conductive materials, have been widely used in chemistry, biomedical, optical, and other fields. [22] Specifically, gold nanowires (AuNWs) are a flexible filamentous structure in the nanoscale and behave like polymer chains because of their ultrathin nature (2 nm in width and >10 000 in aspect ratio). [23] AuNWs have the advantages of high chemical inertness, good biocompatibility, wide electrochemical window, high conductivity, and easy surface modification that depends on thiol gold chemistry. Zhang and co-workers reported a pulse monitoring sensor based on AuNWs and polyacrylamide