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An electrochemical sensing device based on a cotton‐thread electrode for real‐time and simultaneous detection of sweat glucose and sweat lactate is reported. The cotton thread surfaces are simply modified by cellulose nanofibers/carbon nanotube ink‐Prussian blue/chitosan to enhance liquid adsorption, bioreceptor immobilization, and sensor performance in addition to minimize potential irritation and allergies on the wearer's skin. The modified thread surfaces are characterized by laser scanning confocal microscopy, scanning electron microscopy, and Fourier transform Raman spectroscopy. Amperometry is carried out via hydrogen peroxide detection for electrochemical characterization of the modified thread electrodes. A circuit and digital readout of this wearable sensor are customized designed to be integrated with thread electrodes for real‐time and simultaneous detection of sweat glucose and sweat lactate. The wristwatch sensing device provides a linear range of 0.025–3 × 10−3 m with a detection limit of 0.025 × 10−3 m for glucose and a linear range of 0.25–35 × 10−3 m with a detection limit of 0.25 × 10−3 m for lactate. This device can effectively determine the cut‐off levels of both glucose and lactate, which can distinguish between a normal individual and one with a diabetic condition. This platform opens a new avenue for noninvasive and real‐time detection of other sweat biomarkers. [ABSTRACT FROM AUTHOR]

A reusable magnetic nanoparticlesbased cryogel optical biosensor was fabricated to determine of sucrose in sugar cane and sugar samples. In this design, magnetic nanoparticles were embedded in cryogel and then the multienzymes were immobilized. The magnetic nanoparticles in cryogel helped separate the immobilized multi-enzyme cryogel biosensor by applying the external magnetic field to reuse for the subsequent detection. The developed cryogel biosensor exhibited good selectivity for sucrose determination with the detection limit of 3 mM and can be reused up to 32 times with good repeatability (<5 % RSD). Furthermore, the proposed optical biosensor can also be utilized for sucrose analysis in sugar cane and sugar samples. [ABSTRACT FROM AUTHOR]