Revolutionizing digital healthcare networks with wearable strain sensors using sustainable fibers

Wearable strain sensors have attracted research interest owing to their poten-tial within digital healthcare,offering smarter tracking,efficient diagnostics,and lower costs.Unlike rigid sensors,fiber-based ones compete with their flexibility,durability,adaptability to body structures as well as eco-friendliness to envi-ronment.Here,the sustainable fiber-based wearable strain sensors for digital health are reviewed,and material,fabrication,and practical healthcare aspects are explored.Typical strain sensors predicated on various sensing modalities,be it resistive,capacitive,piezoelectric,or triboelectric,are explained and analyzed according to their strengths and weaknesses toward fabrication and applica-tions.The applications in digital healthcare spanning from body area sensing networks,intelligent health management,and medical rehabilitation to mul-tifunctional healthcare systems are also evaluated.Moreover,to create a more complete digital health network,wired and wireless methods of data collec-tion and examples of machine learning are elaborated in detail.Finally,the prevailing challenges and prospective insights into the advancement of novel fibers,enhancement of sensing precision and wearability,and the establishment of seamlessly integrated systems are critically summarized and offered.This endeavor not only encapsulates the present landscape but also lays the founda-tion for future breakthroughs in fiber-based wearable strain sensor technology within the domain of digital health.

Calotropis gigantea Fiber‑Based Sensitivity‑Tunable Strain Sensors with Insensitive Response to Wearable Microclimate Changes

Wearable tensile strain sensors have attracted substantial research interest due to their great potential in applications for the real-time detection of human motion and health through the construction of body-sensing networks.Conventional devices,however,are constantly demonstrated in non-real world scenarios,where changes in body temperature and humidity are ignored,which results in questionable sensing accuracy and reliability in practical applications.In this work,a fabric-like strain sensor is developed by fabricating graphene-modified Calotropis gigantea yarn and elastic yarn(i.e.Spandex)into an independently crossed structure,enabling the sensor with tunable sensitivity by directly altering the sensor width.The sensor possesses excellent breathability,allowing water vapor generated by body skin to be discharged into the environment(the water evaporation rate is approximately 2.03 kg m^(-2) h^(-1))and creating a pleasing microenvironment between the sensor and the skin by avoiding the hindering of perspiration release.More importantly,the sensor is shown to have a sensing stability towards changes in temperature and humidity,implementing sensing reliability against complex and changeable wearable microclimate.By wearing the sensor at various locations of the human body,a full-range body area sensing network for monitoring various body movements and vital signs,such as speaking,coughing,breathing and walking,is successfully dem-onstrated.It provides a new route for achieving wearing-comfortable,high-performance and sensing-reliable strain sensors.

Flexible,breathable,and reinforced ultra-thin Cu/PLLA porous-fibrous membranes for thermal management and electromagnetic interference shielding

Electromagnetic interference shielding and thermal management by wearable devices show great po-tential in emerging digital healthcare.Conventional metal films implementing the functions must sacri-fice either flexibility or permeability,which is far from optimal in practical applications.In this work,an ultra-thin(15μm),flexible,and porous Cu/PLLA fibrous membrane is developed by depositing cop-per particles on the polymer substrate.With novel acetone&heat treatment procedure,the mem-brane is considerably stronger while maintaining the porous fibre structure.Its fantastic breathabil-ity and super high electrical conductivity(9471.8130 S/cm)enable the composites to have fast electri-cal heating characteristics and excellent thermal conductivity for effective thermal management.Mean-while,the porous polymer substrate structure greatly enhances the diffusion of conductive substances and increases the electromagnetic interference shielding effectiveness of the membranes(7797.98 dB cm^(2)/g at the H band and 8072.73 dB cm^(2)/g at the Ku band respectively).The composites present high flexibility,breathability,and strength with the functions of thermal management and electromag-netic shielding,showing great potential for future portable electronic devices and wearable integrated garments.