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simplicity of design. [10,11] Several requirements such as high stretchability, flexibility, a wide working strain range from a subtle region to a large region, durability, lightweight, and low energy consumption should be fulfilled for wearable devices. [12] To achieve the stretchable flexible devices, studies on stretchable elastomeric substrates consisting of highly conductive fillers have been reported. [13,14] Ding et al. demonstrated a scalable and facile preparation of the electrospun polyurethane (PU) nonwoven dip-coated with the conducting polymer poly(3,4-ethylened ioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), which possessed adjustable electrical conductivity in the range of 30-200 S m −1 and large stretchability of 400%. [15] Lu et al. reported a sandwich-structured strain sensor with a gauge factor (GF) of 12.9 (at 20% strain) and a sensing range of 0-50% based on attaching the silver nanowires (AgNWs) on the thermoplastic polyurethane electrospun membrane (TPUEM) by filtration, followed by spin-coating using the liquid polydimethylsiloxane (PDMS). [16] Recently, electrospinning has become an effective, facile, and scalable technique for preparation of micro/nanofibers applied in wide applications. [17][18][19] The electrospun fibers own numerous advantages such as large specific surface area, high porosity, fine diameter, and commendable mechanical flexibility, which is an ideal base material for functional composites. [20,21] Especially, thermoplastic polyurethane (TPU) was easily electrospun into fibrous membrane which displayed outstanding stretchability, flexibility, and mechanical strength. [22,23] However, the pristine TPUEM has no conductivity and cannot be serving as sensing materials solely. Diverse conductive fillers incorporate into TPUEM to be developed as stretchable strain sensors. Yan et al. fabricated electrospun TPU fiber yarns successively decorated with multiwalled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs) for wearable strain sensors. [24] Wang et al. developed a novel strain sensor with an excellent 3D conductive network based on reduced graphene oxide (RGO)-decorated TPU mats. [25] Tian fabricated electrospun PU/polyaniline nanofibrous mat by in situ chemical polymerization of aniline monomers on the surface of electrospun PU nanofiber substrate for wearable device. [26] However, it is quite difficult to Highly stretchable, conductive, and sensitive strain-sensing materials have aroused wide interest owing to their potential in wearable devices. A facile and scalable method to fabricate a carbon-nanotube-(CNT-) bridged silver nanoparticles (AgNPs) strain sensor based on thermoplastic polyurethane electrospun membrane (TPUEM), which exhibits a large strain range with a high gauge factor simultaneously, is demonstrated. It exhibits a high stretchability with large workable strain range of up to 550%, high gauge factor of 7066, good durability over 1000 cycles, and comparable stability under various strains. Importantly, it can be used for human mo...

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A novel phenolic biosensor was prepared on the basis of a composite of polydopamine (PDA)-laccase (Lac)-nickel nanoparticle loaded carbon nanofibers (NiCNFs). First, NiCNFs were fabricated by a combination of electrospinning and a high temperature carbonization technique. Subsequently, the magnetic composite was obtained through one-pot Lac-catalyzed oxidation of dopamine (DA) in an aqueous suspension containing Lac, NiCNFs, and DA. Finally, a magnetic glass carbon electrode (MGCE) was employed to separate and immobilize the composite; the modified electrode was then denoted as PDA-Lac-NiCNFs/MGCE. Fourier transform infrared (FT-IR) spectra and cyclic voltammetry (CV) analyses revealed the NiCNFs had good biocompatibility for Lac immobilization and greatly facilitated the direct electron transfer between Lac and electrode surface. The immobilized Lac showed a pair of stable and well-defined redox peaks, and the electrochemical behavior of Lac was a surface-controlled process in pH 5.5 acetate buffer solution. The PDA-Lac-NiCNFs/MGCE for biosensing of catechol exhibited a sensitivity of 25 μA mM(-1) cm(-2), a detection limit of 0.69 μM (S/N = 3), and a linear range from 1 μM to 9.1 mM, as well as good selectivity and stability. Meanwhile, this novel biosensor demonstrated its promising application in detecting catechol in real water samples.