Advances in flexible electronic materials and smart textile, along with broad availability of smart phones, cloud and wireless systems have empowered the wearable technologies for significant impact on future of digital and personalized healthcare as well as consumer electronics. However, challenges related to lack of accuracy, reliability, high power consumption, rigid or bulky form factor and difficulty in interpretation of data have limited their wide-scale application in these potential areas. As an important solution to these challenges, we present latest advances in novel flexible electronic materials and sensors that enable comfortable and conformable body interaction and potential for invisible integration within daily apparel. Advances in novel flexible materials and sensors are described for wearable monitoring of human vital signs including, body temperature, respiratory rate and heart rate, muscle movements and activity. We then present advances in signal processing focusing on motion and noise artifact removal, data mining and aspects of sensor fusion relevant to future clinical applications of wearable technology.

In the present work, polylactic acid (PLA) microcapsules as novel drug delivery systems were successfully fabricated by one-step processing using an electrospray technique. Curcumin (Cur) was chosen as model drug with satisfactory loading capacity (LC%) and entrapment efficiency (EE%) greater than 95%. By judiciously adjusting spinning solvents, flow rates, polymer and drug concentrations, the monodisperse and spherical structures of Cur/PLA microcapsules observed using scanning electron microscopy (SEM) and optical microscopy were successfully generated with diameter distribution ranging from 3.8 μm to 4.4 μm. The physical-chemical characterization including, FTIR, XRD, TG, and DTA, are explored and in vitro release profiles described by Ritger–Peppas models were also investigated, showing sustained release for 200 h after a burst release in the initial 12 h. The drug-loaded microcapsules showed excellent anti-bacterial activities towards Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by using both disk diffusion and minimal inhibitory concentration methods. The anti-oxidant performance was also evaluated by using DPPH assays. In vitro cell tests, including Cell Counting Kit-8, hemolysis experiments, and cell adhesion revealed that PLA-based microcapsules had significant biocompatibility and low cytotoxicity. The study showed that the PLA-based electrospray strategy combined with spherical microcapsules has the potential for a broad range of applications in medical fields, especially in drug delivery.

Formaldehyde is a volatile organic compound that is widely used in textiles, paper, wood composites, and household materials. Formaldehyde will continuously outgas from manufactured wood products such as furniture, with adverse health effects resulting from prolonged low-level exposure. New, microfabricated sensors for formaldehyde have been developed to meet the need for portable, low-power gas detection. This paper reviews recent work including silicon microhotplates for metal oxide-based detection, enzyme-based electrochemical sensors, and nanowire-based sensors. This paper also investigates the promise of polymer-based sensors for low-temperature, low-power operation.

Surface modification of electrospun lignin nanofibres with poly(N-isopropylacrylamide) (PNIPAM) was conducted through surface-initiated atom transfer radical polymerization (ATRPase) using various biocatalysts under aqueous conditions. Three biocatalysts were investigated, a catalase from bovine liver (CBL), a peroxidase from horseradish (HRP), and a laccase from Trametes versicolor (LTV). All of the biocatalysts were found to successfully graft PNIPAM polymer brushes from the nanofibre surfaces. PNIPAM brush thickness was dependent on enzyme activity and significantly influenced by the reaction conditions; manipulating the type of enzyme, the concentration of reducing reagent and solution pH resulted in PNIPAM brushes of various molecular weight, thickness, and grafting density. Lignin fibre surface immobilized PNIPAM brushes with a thickness of >100 nm and a corresponding molecular weight of more than 1 × 10⁶ g mol⁻¹ and a polydispersity index of less than 1.30 were obtained using LTV as the catalyst and ascorbic acid as the reducing agent. The effect of reducing reagent on the weight percentage of PNIPAM on the nanofibre surface was determined by measuring the enthalpy (ΔH) of the phase transition, which was found to exhibit a similar trend as that of the measured PNIPAM brush thickness. Finally, the low critical solution temperature (LCST) of PNIPAM immobilized lignin nanofibre was similar to that of pure PNIPAM and decreased with increasing the ionic concentration, which simultaneously changed the modified fibre mats from hydrophilic to hydrophobic.